U.S. patent application number 15/959638 was filed with the patent office on 2018-08-23 for method and apparatus for selected internet protocol (ip) traffic offload (sipto) and local ip access (lipa) mobility.
The applicant listed for this patent is InterDigital Patent Holdings, Inc.. Invention is credited to Pascal M. Adjakple, Kai Liu, Peter S. Wang.
Application Number | 20180242213 15/959638 |
Document ID | / |
Family ID | 46514815 |
Filed Date | 2018-08-23 |
United States Patent
Application |
20180242213 |
Kind Code |
A1 |
Liu; Kai ; et al. |
August 23, 2018 |
METHOD AND APPARATUS FOR SELECTED INTERNET PROTOCOL (IP) TRAFFIC
OFFLOAD (SIPTO) AND LOCAL IP ACCESS (LIPA) MOBILITY
Abstract
Methods and apparatus are described for supporting wireless
transmit/receive unit (WTRU) mobility between Home (evolved) Node
Bs (H(e)NBs) that are configured to communicate with a Local
Gateway (L-GW). The H(e)NBs and/or L-GW may belong to one or more
Local H(e)NB Networks (LHNs). A WTRU may receive services including
Selected Internet Protocol (IP) Traffic Offload (SIPTO) or Local IP
Access (LIPA) services from the L-GW via one or more H(e)NBs. The
WTRU may continue to receive SIPTO or LIPA services after a
handover to another H(e)NB that may be in communication with the
same L-GW and may belong to the same LHN. The WTRU may receive
information related to the LHN or the L-GW to allow continuation of
SIPTO or LIPA services as the WTRU moves among H(e)NBs and/or out
of the LHN. The WTRU may receive and/or maintain one or more LHN
Lists.
Inventors: |
Liu; Kai; (Dublin, OH)
; Wang; Peter S.; (E. Setauket, NY) ; Adjakple;
Pascal M.; (Melville, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
InterDigital Patent Holdings, Inc. |
Wilmington |
DE |
US |
|
|
Family ID: |
46514815 |
Appl. No.: |
15/959638 |
Filed: |
April 23, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15217288 |
Jul 22, 2016 |
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15959638 |
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13538732 |
Jun 29, 2012 |
9439060 |
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15217288 |
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61503711 |
Jul 1, 2011 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 88/16 20130101;
H04W 36/0061 20130101; H04W 8/082 20130101; H04W 48/20 20130101;
H04W 80/04 20130101; H04W 84/042 20130101; H04W 84/045 20130101;
H04W 36/08 20130101; H04W 36/0083 20130101 |
International
Class: |
H04W 36/08 20090101
H04W036/08; H04W 36/00 20090101 H04W036/00; H04W 48/20 20090101
H04W048/20; H04W 8/08 20090101 H04W008/08 |
Claims
1.-20. (canceled)
21. A method for use in a wireless transmit/receive unit (WTRU),
the method comprising: receiving a service from a gateway via a
first base station (BS) belonging to a local network (LN) included
in a Service Continuity Area (SCA); maintaining service continuity
information including information related to any number of tracking
areas associated with the SCA; receiving any of LN information and
information related to a second BS associated with the SCA;
attempting to communicate with the second BS according to any of:
the service continuity information, LN information, or information
related to a second BS associated with the SCA; and receiving the
service from the L-GW via the second BS.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/503,711, filed Jul. 1, 2011, the content of
which is hereby incorporated by reference herein.
BACKGROUND
[0002] Selected Internet Protocol (IP) traffic offload (SIPTO) is a
method to offload traffic from a wireless communication system
operator's core network (CN) to a defined IP network that is close
to a point of attachment to the access point of a wireless transmit
receive unit (WTRU). The traffic may be offloaded to another path
based on the geographical (or topological in terms of IP) location
of a WTRU. Thus, a goal of SIPTO is to offload some of the IP
traffic from traversing nodes at the CN. Local IP Access (LIPA) is
a method for providing access for IP-capable WTRUs that are
connected via an H(e)NB (for example, using H(e)NB radio access) to
other IP capable entities in the same residential or enterprise IP
network. Traffic for LIPA typically does not traverse the mobile
operator's network except for accessing particular information at
the H(e)NB. A packet data network (PDN) connection established for
the WTRU may be used for SIPTO and/or LIPA without the WTRU being
aware of the use of SIPTO and/or LIPA.
[0003] In a wireless network capable of providing SIPTO or LIPA
services, a Local Gateway (L-GW) may be located apart from an
H(e)NB. Accordingly, a WTRU may be capable of moving between
H(e)NBs while still maintaining a connection to one L-GW. The WTRU
may therefore be able to continue to receive SIPTO or LIPA services
while moving between H(e)NBs. Local H(e)NB Networks (LHNs) are
networks that include one or more H(e)NBs that are in communication
with a given L-GW. A LHN may also include H(e)NBs that belong to
more than one Closed Subscriber Group (CSG). Based on the
separation of the L-GW from the H(e)NBs and the potential handover
of the WTRU between more than one H(e)NB, methods are needed to
support WTRU mobility between H(e)NBs and to support SIPTO and/or
LIPA services during WTRU mobility.
SUMMARY
[0004] Methods and apparatus are described for supporting wireless
transmit/receive unit (WTRU) mobility between Home (evolved) Node
Bs (H(e)NBs) that are configured to communicate with a Local
Gateway (L-GW). The H(e)NBs and/or L-GW may belong to one or more
Local H(e)NB Networks (LHNs). A WTRU may receive services including
Selected Internet Protocol (IP) Traffic Offload (SIPTO) or Local IP
Access (LIPA) services from the L-GW via one or more H(e)NBs. The
WTRU may continue to receive SIPTO or LIPA services after a
handover to another H(e)NB that may be in communication with the
same L-GW and may belong to the same LHN. The WTRU may receive
information related to the LHN or the L-GW to allow continuation of
SIPTO or LIPA services as the WTRU moves among H(e)NBs and/or out
of the LHN. The WTRU may receive and/or maintain one or more LHN
Lists.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] A more detailed understanding may be had from the following
description, given by way of example in conjunction with the
accompanying drawings wherein:
[0006] FIG. 1A shows an example communications system in which one
or more disclosed embodiments may be implemented;
[0007] FIG. 1B shows an example wireless transmit/receive unit
(WTRU) that may be used within the communications system shown in
FIG. 1A;
[0008] FIG. 1C shows an example radio access network and an example
core network (CN) that may be used within the communications system
shown in FIG. 1A;
[0009] FIG. 2 is an example architecture of a wireless network
configured to perform Selected IP Traffic Offload (SIPTO);
[0010] FIG. 3 shows an example wireless network configured to
provide Local IP Access (LIPA) services;
[0011] FIG. 4 shows an example of a wireless network configured to
perform SIPTO or LIPA services;
[0012] FIG. 5 shows an example of a wireless network that includes
a plurality of Local H(e)NB Networks (LHNs);
[0013] FIG. 6 shows an example of WTRU mobility among multiple
H(e)NBs that connect to the same L-GW;
[0014] FIG. 7 shows an example wireless network with a standalone
logical L-GW configured to provide SIPTO or LIPA services;
[0015] FIG. 8 shows an example wireless network with a standalone
logical L-GW configured to provide SIPTO or LIPA services;
[0016] FIG. 9 shows an example wireless network with a standalone
logical L-GW configured to provide SIPTO or LIPA services;
[0017] FIG. 10 shows an example wireless network configured to
provide SIPTO or LIPA services with a standalone logical L-GW
located along an S1/Iu path;
[0018] FIG. 11 shows an example wireless network configured to
provide SIPTO or LIPA services with a standalone logical L-GW
located along an S1/Iu path;
[0019] FIG. 12 shows an example wireless network configured to
provide SIPTO or LIPA services with a standalone logical L-GW
located along an S1/Iu path;
[0020] FIG. 13 shows an example an Allowed LHN List;
[0021] FIG. 14 shows an example call-flow diagram for a successful
L-GW register procedure;
[0022] FIG. 15 shows an example call-flow diagram for an
unsuccessful L-GW register procedure;
[0023] FIG. 16 shows an example call-flow diagram for an L-GW
deregistration procedure that originates at the L-GW; and
[0024] FIG. 17 shows an example call-flow diagram for an L-GW
deregistration procedure that originates at the H(e)NB-Gateway
(GW).
DETAILED DESCRIPTION
[0025] When referred to hereafter, the terminology "wireless
transmit/receive unit (WTRU)" includes but is not limited to a
user, a user equipment (UE), a mobile station, a fixed or mobile
subscriber unit, a pager, a cellular telephone, a personal digital
assistant (PDA), a computer, or any other type of user device
capable of operating in a wireless environment. When referred to
hereafter, the terminology "base station" includes but is not
limited to a Node-B, an evolved Node-B (eNB), a site controller, an
access point (AP), or any other type of interfacing device capable
of operating in a wireless environment.
[0026] FIG. 1A is a diagram of an example communications system 100
in which one or more disclosed embodiments may be implemented. The
communications system 100 may be a multiple access system that
provides content, such as voice, data, video, messaging, broadcast,
etc., to multiple wireless users. The communications system 100 may
enable multiple wireless users to access such content through the
sharing of system resources, including wireless bandwidth. For
example, the communications systems 100 may employ one or more
channel access methods, such as code division multiple access
(CDMA), time division multiple access (TDMA), frequency division
multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier
FDMA (SC-FDMA), and the like.
[0027] As shown in FIG. 1A, the communications system 100 may
include wireless transmit/receive units (WTRUs) 102a, 102b, 102c,
102d, a radio access network (RAN) 104, a core network 106, a
public switched telephone network (PSTN) 108, the Internet 110, and
other networks 112, though it will be appreciated that the
disclosed embodiments contemplate any number of WTRUs, base
stations, networks, and/or network elements. Each of the WTRUs
102a, 102b, 102c, 102d may be any type of device configured to
operate and/or communicate in a wireless environment. By way of
example, the WTRUs 102a, 102b, 102c, 102d may be configured to
transmit and/or receive wireless signals and may include user
equipment (UE), a mobile station, a fixed or mobile subscriber
unit, a pager, a cellular telephone, a personal digital assistant
(PDA), a smartphone, a laptop, a netbook, a personal computer, a
wireless sensor, consumer electronics, and the like.
[0028] The communications systems 100 may also include a base
station 114a and a base station 114b. Each of the base stations
114a, 114b may be any type of device configured to wirelessly
interface with at least one of the WTRUs 102a, 102b, 102c, 102d to
facilitate access to one or more communication networks, such as
the core network 106, the Internet 110, and/or the networks 112. By
way of example, the base stations 114a, 114b may be a base
transceiver station (BTS), a Node-B, an eNode B, a Home Node B, a
Home eNode B, a site controller, an access point (AP), a wireless
router, and the like. While the base stations 114a, 114b are each
depicted as a single element, it will be appreciated that the base
stations 114a, 114b may include any number of interconnected base
stations and/or network elements.
[0029] The base station 114a may be part of the RAN 104, which may
also include other base stations and/or network elements (not
shown), such as a base station controller (BSC), a radio network
controller (RNC), relay nodes, etc. The base station 114a and/or
the base station 114b may be configured to transmit and/or receive
wireless signals within a particular geographic region, which may
be referred to as a cell (not shown). The cell may further be
divided into cell sectors. For example, the cell associated with
the base station 114a may be divided into three sectors. Thus, in
one embodiment, the base station 114a may include three
transceivers, i.e., one for each sector of the cell. In another
embodiment, the base station 114a may employ multiple-input
multiple output (MIMO) technology and, therefore, may utilize
multiple transceivers for each sector of the cell.
[0030] The base stations 114a, 114b may communicate with one or
more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116,
which may be any suitable wireless communication link (e.g., radio
frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible
light, etc.). The air interface 116 may be established using any
suitable radio access technology (RAT).
[0031] More specifically, as noted above, the communications system
100 may be a multiple access system and may employ one or more
channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA,
and the like. For example, the base station 114a in the RAN 104 and
the WTRUs 102a, 102b, 102c may implement a radio technology such as
Universal Mobile Telecommunications System (UMTS) Terrestrial Radio
Access (UTRA), which may establish the air interface 116 using
wideband CDMA (WCDMA). WCDMA may include communication protocols
such as High-Speed Packet Access (HSPA) and/or Evolved HSPA
(HSPA+). HSPA may include High-Speed Downlink Packet Access (HSDPA)
and/or High-Speed Uplink Packet Access (HSUPA).
[0032] In another embodiment, the base station 114a and the WTRUs
102a, 102b, 102c may implement a radio technology such as Evolved
UMTS Terrestrial Radio Access (E-UTRA), which may establish the air
interface 116 using Long Term Evolution (LTE) and/or LTE-Advanced
(LTE-A).
[0033] In other embodiments, the base station 114a and the WTRUs
102a, 102b, 102c may implement radio technologies such as IEEE
802.16 (i.e., Worldwide Interoperability for Microwave Access
(WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard
2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856
(IS-856), Global System for Mobile communications (GSM), Enhanced
Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and the
like.
[0034] The base station 114b in FIG. 1A may be a wireless router,
Home Node B, Home eNode B, or access point, for example, and may
utilize any suitable RAT for facilitating wireless connectivity in
a localized area, such as a place of business, a home, a vehicle, a
campus, and the like. In one embodiment, the base station 114b and
the WTRUs 102c, 102d may implement a radio technology such as IEEE
802.11 to establish a wireless local area network (WLAN). In
another embodiment, the base station 114b and the WTRUs 102c, 102d
may implement a radio technology such as IEEE 802.15 to establish a
wireless personal area network (WPAN). In yet another embodiment,
the base station 114b and the WTRUs 102c, 102d may utilize a
cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, etc.)
to establish a picocell or femtocell. As shown in FIG. 1A, the base
station 114b may have a direct connection to the Internet 110.
Thus, the base station 114b may not be required to access the
Internet 110 via the core network 106.
[0035] The RAN 104 may be in communication with the core network
106, which may be any type of network configured to provide voice,
data, applications, and/or voice over internet protocol (VoIP)
services to one or more of the WTRUs 102a, 102b, 102c, 102d. For
example, the core network 106 may provide call control, billing
services, mobile location-based services, pre-paid calling,
Internet connectivity, video distribution, etc., and/or perform
high-level security functions, such as user authentication.
Although not shown in FIG. 1A, it will be appreciated that the RAN
104 and/or the core network 106 may be in direct or indirect
communication with other RANs that employ the same RAT as the RAN
104 or a different RAT. For example, in addition to being connected
to the RAN 104, which may be utilizing an E-UTRA radio technology,
the core network 106 may also be in communication with another RAN
(not shown) employing a GSM radio technology.
[0036] The core network 106 may also serve as a gateway for the
WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet
110, and/or other networks 112. The PSTN 108 may include
circuit-switched telephone networks that provide plain old
telephone service (POTS). The Internet 110 may include a global
system of interconnected computer networks and devices that use
common communication protocols, such as the transmission control
protocol (TCP), user datagram protocol (UDP) and the internet
protocol (IP) in the TCP/IP internet protocol suite. The networks
112 may include wired or wireless communications networks owned
and/or operated by other service providers. For example, the
networks 112 may include another core network connected to one or
more RANs, which may employ the same RAT as the RAN 104 or a
different RAT.
[0037] Some or all of the WTRUs 102a, 102b, 102c, 102d in the
communications system 100 may include multi-mode capabilities,
i.e., the WTRUs 102a, 102b, 102c, 102d may include multiple
transceivers for communicating with different wireless networks
over different wireless links. For example, the WTRU 102c shown in
FIG. 1A may be configured to communicate with the base station
114a, which may employ a cellular-based radio technology, and with
the base station 114b, which may employ an IEEE 802 radio
technology.
[0038] FIG. 1B is a system diagram of an example WTRU 102. As shown
in FIG. 1B, the WTRU 102 may include a processor 118, a transceiver
120, a transmit/receive element 122, a speaker/microphone 124, a
keypad 126, a display/touchpad 128, non-removable memory 130,
removable memory 132, a power source 134, a global positioning
system (GPS) chipset 136, and other peripherals 138. It will be
appreciated that the WTRU 102 may include any sub-combination of
the foregoing elements while remaining consistent with an
embodiment.
[0039] The processor 118 may be a general purpose processor, a
special purpose processor, a conventional processor, a digital
signal processor (DSP), a plurality of microprocessors, one or more
microprocessors in association with a DSP core, a controller, a
microcontroller, Application Specific Integrated Circuits (ASICs),
Field Programmable Gate Array (FPGAs) circuits, any other type of
integrated circuit (IC), a state machine, and the like. The
processor 118 may perform signal coding, data processing, power
control, input/output processing, and/or any other functionality
that enables the WTRU 102 to operate in a wireless environment. The
processor 118 may be coupled to the transceiver 120, which may be
coupled to the transmit/receive element 122. While FIG. 1B depicts
the processor 118 and the transceiver 120 as separate components,
it will be appreciated that the processor 118 and the transceiver
120 may be integrated together in an electronic package or
chip.
[0040] The transmit/receive element 122 may be configured to
transmit signals to, or receive signals from, a base station (e.g.,
the base station 114a) over the air interface 116. For example, in
one embodiment, the transmit/receive element 122 may be an antenna
configured to transmit and/or receive RF signals. In another
embodiment, the transmit/receive element 122 may be an
emitter/detector configured to transmit and/or receive IR, UV, or
visible light signals, for example. In yet another embodiment, the
transmit/receive element 122 may be configured to transmit and
receive both RF and light signals. It will be appreciated that the
transmit/receive element 122 may be configured to transmit and/or
receive any combination of wireless signals.
[0041] In addition, although the transmit/receive element 122 is
depicted in FIG. 1B as a single element, the WTRU 102 may include
any number of transmit/receive elements 122. More specifically, the
WTRU 102 may employ MIMO technology. Thus, in one embodiment, the
WTRU 102 may include two or more transmit/receive elements 122
(e.g., multiple antennas) for transmitting and receiving wireless
signals over the air interface 116.
[0042] The transceiver 120 may be configured to modulate the
signals that are to be transmitted by the transmit/receive element
122 and to demodulate the signals that are received by the
transmit/receive element 122. As noted above, the WTRU 102 may have
multi-mode capabilities. Thus, the transceiver 120 may include
multiple transceivers for enabling the WTRU 102 to communicate via
multiple RATs, such as UTRA and IEEE 802.11, for example.
[0043] The processor 118 of the WTRU 102 may be coupled to, and may
receive user input data from, the speaker/microphone 124, the
keypad 126, and/or the display/touchpad 128 (e.g., a liquid crystal
display (LCD) display unit or organic light-emitting diode (OLED)
display unit). The processor 118 may also output user data to the
speaker/microphone 124, the keypad 126, and/or the display/touchpad
128. In addition, the processor 118 may access information from,
and store data in, any type of suitable memory, such as the
non-removable memory 130 and/or the removable memory 132. The
non-removable memory 130 may include random-access memory (RAM),
read-only memory (ROM), a hard disk, or any other type of memory
storage device. The removable memory 132 may include a subscriber
identity module (SIM) card, a memory stick, a secure digital (SD)
memory card, and the like. In other embodiments, the processor 118
may access information from, and store data in, memory that is not
physically located on the WTRU 102, such as on a server or a home
computer (not shown).
[0044] The processor 118 may receive power from the power source
134, and may be configured to distribute and/or control the power
to the other components in the WTRU 102. The power source 134 may
be any suitable device for powering the WTRU 102. For example, the
power source 134 may include one or more dry cell batteries (e.g.,
nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride
(NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and
the like.
[0045] The processor 118 may also be coupled to the GPS chipset
136, which may be configured to provide location information (e.g.,
longitude and latitude) regarding the current location of the WTRU
102. In addition to, or in lieu of, the information from the GPS
chipset 136, the WTRU 102 may receive location information over the
air interface 116 from a base station (e.g., base stations 114a,
114b) and/or determine its location based on the timing of the
signals being received from two or more nearby base stations. It
will be appreciated that the WTRU 102 may acquire location
information by way of any suitable location-determination method
while remaining consistent with an embodiment.
[0046] The processor 118 may further be coupled to other
peripherals 138, which may include one or more software and/or
hardware modules that provide additional features, functionality
and/or wired or wireless connectivity. For example, the peripherals
138 may include an accelerometer, an e-compass, a satellite
transceiver, a digital camera (for photographs or video), a
universal serial bus (USB) port, a vibration device, a television
transceiver, a hands free headset, a Bluetooth.RTM. module, a
frequency modulated (FM) radio unit, a digital music player, a
media player, a video game player module, an Internet browser, and
the like.
[0047] FIG. 1C is a system diagram of the RAN 104 and the core
network 106 according to an embodiment. As noted above, the RAN 104
may employ an E-UTRA radio technology to communicate with the WTRUs
102a, 102b, 102c over the air interface 116. The RAN 104 may also
be in communication with the core network 106.
[0048] The RAN 104 may include eNode-Bs 140a, 140b, 140c, though it
will be appreciated that the RAN 104 may include any number of
eNode-Bs while remaining consistent with an embodiment. The
eNode-Bs 140a, 140b, 140c may each include one or more transceivers
for communicating with the WTRUs 102a, 102b, 102c over the air
interface 116. In one embodiment, the eNode-Bs 140a, 140b, 140c may
implement MIMO technology. Thus, the eNode-B 140a, for example, may
use multiple antennas to transmit wireless signals to, and receive
wireless signals from, the WTRU 102a.
[0049] Each of the eNode-Bs 140a, 140b, 140c may be associated with
a particular cell (not shown) and may be configured to handle radio
resource management decisions, handover decisions, scheduling of
users in the uplink and/or downlink, and the like. As shown in FIG.
1C, the eNode-Bs 140a, 140b, 140c may communicate with one another
over an X2 interface.
[0050] The core network 106 shown in FIG. 1C may include a mobility
management gateway (MME) 142, a serving gateway 144, and a packet
data network (PDN) gateway 146. While each of the foregoing
elements are depicted as part of the core network 106, it will be
appreciated that any one of these elements may be owned and/or
operated by an entity other than the core network operator.
[0051] The MME 142 may be connected to each of the eNode-Bs 142a,
142b, 142c in the RAN 104 via an S1 interface and may serve as a
control node. For example, the MME 142 may be responsible for
authenticating users of the WTRUs 102a, 102b, 102c, bearer
activation/deactivation, selecting a particular serving gateway
during an initial attach of the WTRUs 102a, 102b, 102c, and the
like. The MME 142 may also provide a control plane function for
switching between the RAN 104 and other RANs (not shown) that
employ other radio technologies, such as GSM or WCDMA.
[0052] The serving gateway 144 may be connected to each of the
eNode Bs 140a, 140b, 140c in the RAN 104 via the Si interface. The
serving gateway 144 may generally route and forward user data
packets to/from the WTRUs 102a, 102b, 102c. The serving gateway 144
may be configured to perform SIPTO or LIPA services. The serving
gateway 144 may also perform other functions, such as anchoring
user planes during inter-eNode B handovers, triggering paging when
downlink data is available for the WTRUs 102a, 102b, 102c, managing
and storing contexts of the WTRUs 102a, 102b, 102c, and the
like.
[0053] The serving gateway 144 may also be connected to the PDN
gateway 146, which may provide the WTRUs 102a, 102b, 102c with
access to packet-switched networks, such as the Internet 110, to
facilitate communications between the WTRUs 102a, 102b, 102c and
IP-enabled devices.
[0054] The core network 106 may facilitate communications with
other networks. For example, the core network 106 may provide the
WTRUs 102a, 102b, 102c with access to circuit-switched networks,
such as the PSTN 108, to facilitate communications between the
WTRUs 102a, 102b, 102c and traditional land-line communications
devices. For example, the core network 106 may include, or may
communicate with, an IP gateway (e.g., an IP multimedia subsystem
(IMS) server) that serves as an interface between the core network
106 and the PSTN 108. In addition, the core network 106 may provide
the WTRUs 102a, 102b, 102c with access to the networks 112, which
may include other wired or wireless networks that are owned and/or
operated by other service providers.
[0055] Selected Internet protocol (IP) traffic offload (SIPTO) and
local IP access (LIPA) services may be provided in any type of
network and may use any type of radio access technology. For
example, SIPTO and LIPA may be used in a universal mobile telephone
system (UMTS) terrestrial radio access network (UTRAN) as well as
an LTE network. The architecture used for SIPTO and LIPA in a UTRAN
or LTE network may be similar. Accordingly, although descriptions
herein may refer to a particular technology, the descriptions are
for exemplary purposes only and one skilled in the art will
appreciate that the descriptions may be applied to any technology
capable of using SIPTO or LIPA services.
[0056] As described above, SIPTO is a method to offload traffic
from a CN to a defined IP network. When reference is made to a core
network with respect to the data plane, the nodes under
consideration may include the serving gateway (S-GW) and the packet
data network (PDN) gateway (P-GW) in, for example, an LTE-compliant
system, or the serving general packet radio service (GPRS) support
node (SGSN) and gateway GPRS support node (GGSN) in a UTRAN,
although the disclosure herein is not limited to any one network
architecture or technology. SIPTO may require that a WTRU processes
both offloaded traffic and non-offloaded (non-SIPTO) traffic that
goes through the operator's network. SIPTO may be used in, for
example, a UTRAN, an evolved UTRAN (E-UTRAN), and/or a macro cell
with a home eNodeB (HeNB), for example.
[0057] FIG. 2 shows an example wireless network 200 configured to
provide SIPTO services. The network 200 includes a WTRU 210 in
communication with an eNB 220 that is located in a radio access
network (RAN) 225. The eNB 220 is also in communication with an
S-GW 230, which is also in communication with a local packet
gateway (L-PGW) 235 and a core network (CN) 240. The CN 240
includes an MME 245 and a packet data network (PDN) gateway (P-GW)
250.
[0058] The WTRU 210 communicates with the eNB 220 over a wireless
air interface 255. The eNB 220 also communicates with the S-GW 230
over an S1-U interface 260. The S-GW 230 communicates with the
L-PGW 235 over an S5 interface 265, and with the P-GW 250 over an
S5 interface 270. The S-GW 230 also communicates with the MME 245
over an S11 interface 275. Two traffic streams are also shown, a
SIPTO traffic stream 280 that is routed through the S-GW 230 to the
L-PGW 235, and a CN traffic stream 285 that is routed through the
S-GW 230 to the P-GW 250 in the CN 240.
[0059] The eNB 220 may also be a HeNB configured to perform SIPTO
in a home network of the user of the WTRU 210. In that case,
traffic may be offloaded locally to a user's home network. The home
network may be an IP network that is connected to other devices
such as a printer, a television, and a personal computer, for
example. These nodes on the home network may be using private
addressing.
[0060] Also, the wireless network 200 may be configured to provide
Local IP Access (LIPA). While many of the features disclosed herein
are described with regard to SIPTO, they may also be applied to
LIPA and SIPTO systems for HeNBs. For example, SIPTO or LIPA may
include single or multiple PDN connections, deployment behind
network address translation (NAT), and the like.
[0061] Furthermore, for traffic going through the mobile operator's
core network, the S-GW 230 user plane functions may be located
within the CN 240. Also, mobility management signalling between a
WTRU 210 and the network may be handled in the CN 240. Session
management signalling, such as bearer setup for SIPTO or LIPA
traffic, and traffic going through the CN 240 may terminate in the
CN 240. Also, reselection of a WTRU's offload point for SIPTO
traffic that is geographically or topologically close to the WTRU
210 may be possible during idle mode mobility procedures.
[0062] The SIPTO system may include a local gateway (L-GW) that is
close to a WTRU's point of attachment to the access network. The
L-GW may perform IP traffic offload based on some policy or
configuration, for example, based on the IP address destination. IP
traffic may go through the L-GW rather than through the operator's
core network via, for example, an S-GW and a P-GW or via an SGSN
and a GGSN (not shown).
[0063] Depending on the network technology, a local break point or
local gateway may be in the HeNB subsystem or in a radio network
controller (RNC). Also, the SGSN may be responsible for both
control and user planes in some networks, while the user and
control planes may be taken care of by a MME and an S-GW in
others.
[0064] An L-GW, such as the L-PGW 235, may have certain
functionalities of a PDW/GGSN. For example, the L-GW may have the
following functionalities: IP address allocation; direct tunneling
with the RAN 225 in connected mode; per WTRU policy-based packet
filtering; or rate policing/shaping. In order to perform SIPTO
transfers to a network, such as a local network or Intranet, for
example, a proper PDN connection may be required. A WTRU may set an
access point name (APN) to a specific value when requesting a PDN
connection or when requesting the establishment of a packet data
protocol (PDP) context.
[0065] FIG. 3 shows an example wireless network 300 configured to
provide LIPA services. A WTRU 310 may be in communication with a
HeNB 320. The HeNB 320 may be collocated with an L-GW 325. The HeNB
320 and the L-GW 325 may be located at a home network 330. A MME
335 and an S-GW 340 may be located at the Evolved Packet Core (EPC)
345. A Security Gateway (SeGW) 350 may be located at the edge of an
operator's core network. The SeGW 350 may maintain a secure
connection with the HeNB 320 across an IP backhaul network 355. A
Home Router/NAT device 360 may be located at a boundary of the home
network 330 and the IP backhaul network 355. A P-GW 365 is also
shown.
[0066] The L-GW 325 may communicate with the S-GW 340 over an S5
interface 370. The WTRU 310 may be paged by sending a packet (for
example, a downlink user packet or any other packet) to the L-GW
325 over the S5 interface 370. Downlink user packets may be
buffered in the L-GW 325. Packets buffered at the L-GW 325 may be
forwarded to the HeNB 320 over a direct link. The HeNB 320 may
communicate with the S-GW 340 over an S1-U interface 375. Packets
buffered at the S-GW 340 may be forwarded to the HeNB 320 over the
S1-U interface 375. The MME 335 may communicate with the HeNB 320
over an S1-MME interface 380. Communications over the S5 interface
370, the S1-U interface 375, and the S1-MME interface 380 may be
tunneled via an IPSec Tunnel 385.
[0067] To perform mapping of enhanced radio access bearer (E-RAB)
IDs at the HeNB 320 with the Evolved Packet System (EPS) Bearer IDs
at the L-GW 325, the S5 interface 370 P-GW tunnel endpoint
identifier (TEID) (user plane) parameter may be used as correlation
information. For example, the TEID may be signaled across the
S1-MME interface 380 to the HeNB 320. Candidate messages may
include an INITIAL CONTEXT SETUP REQUEST, an E-RAB SETUP REQUEST,
or the like. IKEv2 mechanisms may be used to request one IP address
each for the HeNB 320 and the L-GW 325 function. The assigned L-GW
address may be signaled to the MME 335 via the S1-MME interface 380
in, for example, WTRU-associated signaling messages. The MME 335
may use the information from the HeNB 320 to override the normal
L-GW 325 selection algorithm. The S-GW 340 may communicate with the
P-GW 365 over an S5 interface 370. The S-GW 340 may communicate
with the MME 335 over an S11 interface 390.
[0068] FIG. 4 shows an example of a wireless network 400 configured
to perform SIPTO or LIPA services. A WTRU 405 may communicate with
one of a plurality of HeNBs 410.sub.1 . . . n. The WTRU 405 and the
plurality of HeNBs 410.sub.1 . . . n, may be located at an
Enterprise Network 415. An L-GW 420 is also located at the
Enterprise Network 415. Each of the HeNBs 410.sub.1 . . . n, may be
in communication with the L-GW 420. The L-GW 420 may also be in
communication with the Internet 425. Each of the HeNBs 410.sub.1 .
. . n, may be in communication with an MME 430 over an S1-MME
interface 435. Each of the HeNBs 410.sub.1 . . . n, may also be in
communication with an S-GW 440 and a P-GW 445 over an S1-U
interface 450. The S-GW 440 and the P-GW 445 may be collocated. The
MME 430, the S-GW 440, and the P-GW 445 may be located at a Mobile
Operator Network 455. An eNB 460 may be in communication with the
MME 430 over an S1-MME interface 435 and may be in communication
with the S-GW 440 and P-GW 445 over an S1-U interface 450. The eNB
460 may be located at an LTE Macro Network 465.
[0069] Traffic offload may be performed at the L-GW 420. In
addition to being in communication with the Internet 425, the L-GW
420 may be in communication with Enterprise IP Services 470. The
traffic offload may be performed from the WTRU 405 through the
HeNBs 410.sub.1 . . . n and the L-GW 420 to the Internet 425. As
shown in FIG. 4, the WTRU 405 may handover from one HeNB 410.sub.2
to another HeNB 410.sub.1 and may continue to perform traffic
offload via the L-GW 420.
[0070] As shown in FIG. 4, a HeNB subsystem may support SIPTO to
provide access from the WTRU 405 connected via a HeNB 410.sub.1 . .
. n via HeNB radio access to a network, such as the Internet 425.
SIPTO may be performed without traversing the Mobile Operator
Network 455. A mobile operator or a HeNB hosting party may enable
or disable SIPTO on a HeNB-by-HeNB basis. Based on SIPTO policies
set by, for example, the mobile operator, the network may be able
to allow a user of the WTRU 405 to accept or decline offload before
traffic is offloaded. SIPTO policies may be defined per APN, per IP
Flow class under any APN, or per IP Flow class under a specific
APN. The mobile operator may configure the SIPTO policies either
statically or dynamically.
[0071] As shown in FIG. 4, the WTRU 405, in communication with at
least one HeNB 410.sub.1 . . . n, may have a LIPA connection that
provides an IP connection to the Enterprise IP Services 470. The
WTRU 405 may also have a SIPTO connection that is offloaded at a
RAN, via the L-GW 420, to the Internet 425. Thus, in FIG. 4, the
L-GW 420 is at the RAN and is standalone. Therefore, in this
example, SIPTO for use with the HeNB subsystem may be offloading IP
traffic from the HeNB subsystem to the Internet. Thus, SIPTO
service may be "closer" to the WTRU because it is available at the
RAN. In other examples, traffic offload may be available beyond the
RAN.
[0072] FIG. 5 shows an example of a wireless network 500 that
includes a plurality of Local H(e)NB Networks (LHNs). The wireless
network 500 may be configured to perform SIPTO or LIPA services.
FIG. 5 shows a plurality of H(e)NBs 510.sub.1-n, two L-GWs
520.sub.1-2, and two Packet Data Networks (PDNs) 530.sub.1-2. In
the example shown in FIG. 5, the plurality of H(e)NBs 510.sub.1-n,
and the two L-GWs 520.sub.1-2 comprise two LHNs 540.sub.1-2. As
described above in detail, each of the L-GWs 520.sub.1-2 is not
collocated with each of the H(e)NBs 510.sub.1-n, which may allow
continuity of a PDN connection as a WTRU (not shown) moves between
the coverage area of more than one of the H(e)NBs 510.sub.1-n.
Thus, multiple H(e)NBs 510.sub.1-n, may connect to one of the L-GWs
520.sub.1-2. As an example, the wireless network 500 may allow a
WTRU (not shown) with a SIPTO or LIPA PDN connection to move
between any of the H(e)NBs 510.sub.1-n (referred to, for example,
as an H(e)NB subsystem) while maintaining the PDN connection with
SIPTO or LIPA services. As shown in FIG. 5, each LHN 540.sub.1,
540.sub.2 may include one L-GW 520.sub.1, 520.sub.2, and each L-GW
520.sub.1, 520.sub.2 may be in communication with at least one of
the H(e)NBs 510.sub.1-n. If a WTRU moves away from one of the LHNs
540.sub.1, 540.sub.2 (for example, the WTRU moves out of the
coverage of all H(e)NBs 510.sub.1-3 that connect to one L-GW
520.sub.1), the PDN connection for SIPTO or LIPA services may be
deactivated.
[0073] FIG. 6 shows an example 600 of WTRU mobility among one or
more H(e)NBs that connect to the same L-GW. The L-GW 605 may be in
communication with one or more H(e)NBs 610.sub.1-n. Each of the one
or more H(e)NBs 610.sub.1-n may be in communication with one or
more WTRUs 615.sub.1-n. For example, at a particular time, a WTRU
615.sub.1 may be in communication with a first H(e)NB 610.sub.1.
The WTRU 615.sub.1 may in communication with the L-GW 605 via the
first H(e)NB 610.sub.1. The WTRU 615.sub.1 may be receiving
services (including, for example, SIPTO and/or LIPA services) from
the L-GW 605. The potential communication paths are shown in FIG.
6. The WTRU 615.sub.1 may disconnect from the first H(e)NB
610.sub.1 and may, at some point in time, connect to a second
H(e)NB 610.sub.2 (shown as WTRU 615.sub.2). The WTRU 615.sub.2 may
be in communication with the L-GW 605 via the second H(e)NB
610.sub.2. Because the second H(e)NB 6102 may be in communication
with the L-GW 605, the WTRU 615.sub.2 may receive and/or resume
services that the WTRU 615.sub.2 was previously receiving via the
first H(e)NB 6101. The potential communication paths are shown in
FIG. 6. The services may include SIPTO and/or LIPA services to
allow for SIPTO and/or LIPA service continuity, for example, after
a handover. The change in the communication paths based on mobility
of the WTRU 615.sub.2 is also shown via for example, the arrows
shown in FIG. 6. Similarly, the WTRU 615.sub.2 may handover to a
third H(e)NB 610.sub.3 (shown as WTRU 615.sub.3) and may receive or
resume services from the L-GW 605 via the third H(e)NB 610.sub.3.
The WTRU 615.sub.3 may handover to a fourth H(e)NB 610.sub.4 (shown
as WTRU 615.sub.4) and may receive or resume services from the L-GW
605 via the fourth H(e)NB 610.sub.4.
[0074] The examples and architecture shown in FIG. 6 are for
purposes of example, and other combinations of nodes, devices, or
handovers are possible. For example, a WTRU may receive services
from one or more H(e)NBs at a particular time and may connect
and/or disconnect from the H(e)NBs in any order at any time.
[0075] FIGS. 7-12 show examples of architectural structures for
supporting an L-GW in a wireless network. an L-GW may be a
standalone L-GW or a standalone L-GW located along an S1/Iu path.
The examples shown in FIGS. 7-12 may be applicable to any
technology, such as, for example but not limited to, LTE or UMTS
systems or wireless networks.
[0076] FIG. 7 shows an example wireless network 700 with a
standalone logical L-GW configured to provide SIPTO or LIPA
services. The L-GW 705 may be used, for example, as part of a HeNB
subsystem. The L-GW 705 may be in communication with a HeNB 710
over an Sxx interface 715. The L-GW 705 may also be in
communication with an S-GW 720 over an S5 interface 725. A SeGW 730
is shown between the L-GW 705 and the S-GW 720 and the SeGW 730 may
maintain a secure connection between the L-GW 705 and the S-GW 720.
The L-GW 705 may also communicate with any other node or device
over an SGi interface 735.
[0077] The HeNB 710 may also be in communication with a WTRU 740
over a Uu interface 745. The HeNB 710 may be in communication with
the S-GW 720 over an S1-U interface 750. The SeGW 730 is shown
between the HeNB 710 and the S-GW 720 and may maintain a secure
connection between the HeNB 710 and the S-GW 720. A HeNB-Gateway
(HeNB-GW) 755 is also shown between the HeNB 710 and the S-GW 720
and may maintain a secure connection between the HeNB 710 and the
S-GW 720. The HeNB 710 may be in communication with an MME 760 over
an S1-MME interface 765. The SeGW 730 is shown between the HeNB 710
and the MME 760 and may maintain a secure connection between the
HeNB 710 and the MME 760. The HeNB-GW 755 is also shown between the
HeNB 710 and the MME 760 and may maintain a secure connection
between the HeNB 710 and the MME 760. The HeNB 710 may also
communicate with any other node or device over an X2 interface 770.
The S-GW 720 and the MME 760 may be in communication over an S11
interface 775.
[0078] FIG. 8 shows an example wireless network 800 with a
standalone logical L-GW configured to provide SIPTO or LIPA
services. The L-GW 805 may be used, for example, as part of an HNB
subsystem. The L-GW 805 may be in communication with an HNB 810
over an Sxx interface 815. The L-GW 805 may also be in
communication with an S-GW 820 over an S5 interface 825. A SeGW 830
is shown between the L-GW 805 and the S-GW 820 and the SeGW 830 may
maintain a secure connection between the L-GW 805 and the S-GW 820.
The L-GW 805 may also communicate with any other node or device
over an SGi interface 835.
[0079] The HNB 810 may also be in communication with a WTRU 840
over a Uu interface 845. The HNB 810 may be in communication with
the S-GW 820. The SeGW 830 is shown between the HNB 810 and the
S-GW 820 and may maintain a secure connection between the HNB 810
and the S-GW 820. An HNB-Gateway (HNB-GW) 855 is also shown between
the HNB 810 and the S-GW 820 and may maintain a secure connection
between the HNB 810 and the S-GW 820. The HNB 810 may communicate
with the HNB-GW 855 over an Iuh interface 850. The HNB-GW855 may
communicate with the S-GW 820 over an Iu-UP interface 860. The HNB
810 may be in communication with an S4-SGSN 865. The SeGW 830 is
shown between the HNB 810 and the S4-SGSN 865 and may maintain a
secure connection between the HNB 810 and the S4-SGSN 865. The
HNB-GW 855 is also shown between the HNB 810 and the S4-SGSN 865
and may maintain a secure connection between the HNB 810 and the
S4-SGSN 865. As described above, the HNB 810 may communicate with
the HNB-GW 855 over an Iuh interface 850. The HNB-GW855 may
communicate with the S4-SGSN 865 over an Iu-CP interface 870. The
HNB 810 may also communicate with any other node or device over an
Iurh interface 875. The S-GW 820 and the S4-SGSN 865 may be in
communication over an S4 interface 880.
[0080] FIG. 9 shows an example wireless network 900 with a
standalone logical L-GW configured to provide SIPTO or LIPA
services. The L-GW 905 may be used, for example, as part of a UMTS
system. The L-GW 905 may be in communication with an HNB 910 over
an Sxx interface 915. The L-GW 905 may also be in communication
with an SGSN 920 over a Gn interface 925. A SeGW 930 is shown
between the L-GW 905 and the SGSN 920 and the SeGW 930 may maintain
a secure connection between the L-GW 905 and the SGSN 920. The L-GW
905 may also communicate with any other node or device over a Gi
interface 935.
[0081] The HNB 910 may also be in communication with a WTRU 940
over a Uu interface 945. The HNB 910 may be in communication with
the SGSN 920. The SeGW 930 is shown between the HNB 910 and the
SGSN 920 and may maintain a secure connection between the HNB 810
and the SGSN 920. An HNB-GW 955 is also shown between the HNB 910
and the SGSN 920 and may maintain a secure connection between the
HNB 910 and the SGSN 920. The HNB 910 may communicate with the
HNB-GW 955 over an Iuh interface 950. The HNB-GW 955 may
communicate with the SGSN 920 over an Iu interface 960. The HNB 910
may also communicate with any other node or device over an Iurh
interface 965.
[0082] FIG. 10 shows an example wireless network 1000 configured to
provide SIPTO or LIPA services with a standalone logical L-GW
located along an S1/Iu path. The L-GW 1005 may be used, for
example, as part of a HeNB subsystem. The L-GW 1005 may be in
communication with a HeNB 1010 over an S1-U interface 1015 and/or
an S1-MME interface 1020. Thus, the L-GW 1005 may be located in a
path between the HeNB 1010 and an S-GW 1025 and an MME 1030. The
L-GW 1005 may be in communication with the S-GW 1025 via the S1-U
interface 1015 and in communication with the MME 1030 via the
S1-MME interface 1020. A SeGW 1035 and a HeNB-GW 1040 are shown
between the L-GW 1005 and the S-GW 1025, and the SeGW 1035 and
HeNB-GW 1040 may maintain a secure connection between the L-GW 1005
and the S-GW 1025. The SeGW 1035 and the HeNB-GW 1040 are shown
between the L-GW 1005 and the MME 1030, and the SeGW 1035 and
HeNB-GW 1040 may maintain a secure connection between the L-GW 1005
and the MME 1030. The L-GW 1005 may also communicate with the S-GW
1025 over an S5 interface 1045. The SeGW 1035 may be between the
L-GW 1005 and the S-GW 1025 over the S5 interface 1045. The L-GW
1005 may also communicate with any other node or device over an SGi
interface 1050.
[0083] The HeNB 1010 may be in communication with a WTRU 1055 over
a Uu interface 1060. The HeNB 1010 may also be in communication
with any other node or device over an X2 interface 1065. The S-GW
1025 and the MME 1030 may be in communication over an S11 interface
1070.
[0084] FIG. 11 shows an example wireless network 1100 configured to
provide SIPTO or LIPA services with a standalone logical L-GW
located along an S1/Iu path. The L-GW 1105 may be used, for
example, as part of an HNB subsystem. The L-GW 1105 may be in
communication with an HNB 1110 over an Iuh interface 1115. Thus,
the L-GW 1105 may be located in a path between the HNB 1110 and an
S-GW 1125 and an S4-SGSN 1130. A SeGW 1135 and an HNB-GW 1140 are
shown between the L-GW 1105 and the S-GW 1125, and the SeGW 1135
and HNB-GW 1140 may maintain a secure connection between the L-GW
1105 and the S-GW 1125. The L-GW 1105 may communicate with the
HNB-GW 1140 over the Iuh interface 1115. The SeGW 1135 and the
HNB-GW 1140 are shown between the L-GW 1105 and the S4-SGSN 1130,
and the SeGW 1135 and HNB-GW 1140 may maintain a secure connection
between the L-GW 1105 and the S4-SGSN 1130. The L-GW 1105 may also
communicate with the S-GW 1125 over an S5 interface 1145. The SeGW
1135 may be between the L-GW 1105 and the S-GW 1125 over the S5
interface 1145. The L-GW 1105 may also communicate with any other
node or device over an SGi interface 1150.
[0085] The HNB 1110 may be in communication with a WTRU 1155 over a
Uu interface 1160. The HNB 1110 may also be in communication with
any other node or device over an Iurh interface 1165. The HNB-GW
1140 may communicate with the S-GW 1125 over an Iu-UP interface
1170. The HNB-GW 1140 may communicate with the S4-SGSN 1130 over an
Iu-CP interface 1175. The S-GW 1125 and the S4-SGSN 1130 may be in
communication over an S4 interface 1180.
[0086] FIG. 12 shows an example wireless network 1200 configured to
provide SIPTO or LIPA services with a standalone logical L-GW
located along an S1/Iu path. The L-GW 1205 may be used, for
example, as part of a UMTS HNB subsystem. The L-GW 1205 may be in
communication with an HNB 1210 over an Iuh interface 1215. Thus,
the L-GW 1205 may be located in a path between the HNB 1210 and an
SGSN 1225. A SeGW 1235 and an HNB-GW 1240 are shown between the
L-GW 1205 and the SGSN 1225, and the SeGW 1235 and HNB-GW 1240 may
maintain a secure connection between the L-GW 1205 and the SGSN
1225. The L-GW 1205 may communicate with the HNB-GW 1240 over the
Iuh interface 1215. The L-GW 1205 may also communicate with the
SGSN 1225 over a Gn interface 1245. The SeGW 1235 may be between
the L-GW 1205 and the SGSN 1225 over the Gn interface 1245. The
L-GW 1205 may also communicate with any other node or device over a
Gi interface 1250.
[0087] The HNB 1210 may be in communication with a WTRU 1255 over a
Uu interface 1260. The HNB 1210 may also be in communication with
any other node or device over an Iurh interface 1265. The HNB-GW
1240 may communicate with the SGSN 1225 over an Iu interface
1270.
[0088] One skilled in the art will recognize that the examples
shown in FIGS. 7-12 are for exemplary purposes only. The nodes and
elements shown (and the corresponding names) are for exemplary
purposes and one skilled in the art will recognize that any node or
interface capable of performing similar functions may be used.
Further, the architectures shown are for purposes of example and
other combinations of nodes and interfaces are possible.
[0089] In order to facilitate WTRU mobility and SIPTO/LIPA services
based on the architecture described above, one or a combination of
the following may be used. Initial system access, including cell
search, attachment, and detachment, is described herein. A WTRU
acquiring information about an L-GW and its Local Home eNB Network
(LHN) to allow SIPTO and LIPA services is also described.
Maintaining desired service continuity as a WTRU moves among HeNBs
or out of the LHN is also described.
[0090] Methods and apparatus are described for improving
identification and authorization of WTRUs and services with
independent L-GWs and LHNs that support LIPA and SIPTO services.
Further, methods for improving WTRU cell search and reselection are
described. For example, a SIPTO and/or LIPA supporting-LHN may be
identified by a WTRU. Rules and configuration details to allow a
WTRU to locate and find an LHN access point to enable SIPTO and/or
LIPA services are described. In addition, WTRU attach procedure
details for network registration to the LHN and/or HeNB for LIPA
and SIPTO are also described.
[0091] Methods and apparatus for identifying SIPTO and/or LIPA
service continuity areas (SCAs) are described. For WTRUs moving
between cells belonging to the same LHN and/or beyond the LHN,
methods for service continuity for SIPTO and/or LIPA are provided.
A WTRU (for example, a WTRU in Idle mode) may support the
SIPTO/LIPA service continuity while the WTRU moves between cells
and potentially between LHNs. In connected mode, for example, in an
X2 handover case, the system may also determine whether the target
cell may support the SIPTO/LIPA continuity before the handover is
performed and before the core network (CN) initiates a path
switch.
[0092] Resolutions to security issues associated with using an
International Mobile Subscriber Identity (IMSI) or Mobile
Subscriber ISDN Number (MSISDN) in a message are described. For
example, the WTRU IMSI may be included in a CREATE SESSION REQUEST
message to the L-GW from the MME if the WTRU has sent an ATTACH
REQUEST to the MME. Since the L-GW may not be under direct control
of the operator, the L-GW may need information related to the user.
To protect the user's privacy and identity at the L-GW, WTRU-IDs
such as, for example, the IMSI or the MSISDN may be protected or
excluded from being included in the CREATE SESSION REQUEST message
sent by the MME during the WTRU ATTACH procedure to enable SIPTO
and/or LIPA services. Accordingly, methods are described for
protecting user information at the L-GW.
[0093] A WTRU may reestablish or resume SIPTO and/or LIPA services
after a Radio Link Failure (RLF). The WTRU may re-connect to
another cell or HeNB and may re-establish the connection that
existed between the old HeNB and the L-GW between the new HeNB and
the L-GW.
[0094] Methods and apparatus for distinguishing and identifying the
different reasons for an unsuccessful WTRU ATTACH REQUEST for SIPTO
and/or LIPA to the MME are described. The MME may be in
communication with the L-GW for admission details and the MME may
provided a reason for an unsuccessful ATTACH procedure. For
example, an L-GW in a LHN may accept a user's SIPTO request, but
reject its LIPA request. Thus, special failure codes and/or
cause/reason codes may be included in, for example, the Create
Session Response Message. The L-GW may therefore be able to
indicate the possible rejection that affected the WTRU ATTACH
REQUEST outcome. Further, based on the type of rejection, the MME
may use policies to handle the rejections and identify the
rejection to the WTRU. LHN access permission rules are specified
for WTRU handling such as, for example, updating any of the LHN
Lists.
[0095] If a network wants to relocate the WTRU's bearer or the
WTRU's current SIPTO bearers to an L-GW (for example, if the WTRU
is not currently under an H(e)NB cell under the LHN/L-GW), the
network may try to handover the WTRU to an H(e)NB within the LHN
and then trigger a detach procedure and then a reattach procedure.
A WTRU may not be able to select to the same cell for the re-attach
procedure and WTRU may select to a cell that does not belong to the
intended LHN. Methods and apparatus are described to avoid
relocation failures and to allow network triggering of relocated
SIPTO and/or LIPA services.
[0096] An H(e)NB may be connected to multiple LHNs or multiple
L-GWs. This may occur in the case of RAN sharing or, for example,
femto network sharing in public areas. It may also occur in the
context of multiple carriers or multiple RATs with different
carriers or RATs mapped to different LHNs. Another example is an
enterprise scenario in which multiple groups of employees are in a
meeting, but the groups belong to different LHNs. Methods and
apparatus are described herein to allow basic access or specific
service access to different LHNs through the same H(e)NB. The
methods and apparatus may be applied during security and access
privilege differentiation.
[0097] As an L-GW is powered up, the L-GW may inform the H(e)NB-GW
that the L-GW is now available at a particular IP address and
therefore may allow the HNB-GW to provide service and core network
connectivity for the L-GW and possibly to the H(e)NBs connected to
the L-GW. Also, since the L-GW is connected to multiple H(e)NBs,
the L-GW may act as an H(e)NB aggregator. For example, if an L-GW
goes down and then comes back up, the individual H(e)NB under the
L-GW may re-register to the core network (via, for example, the
H(e)NB-GW) or the L-GW may act as an aggregator and register its
H(e)NBs toward the H(e)NB-GW.
[0098] The methods described below may apply to several system
areas and/or procedures and the examples described herein are for
exemplary purposes only. For example, the examples may relate to
Radio Resource Control (RRC), Non-Access Stratum (NAS), or any
other combination or layer. Further, the methods may be applied in
combination with any other solution under any other system
area.
[0099] A WTRU may be configured to find, search for, identify, or
locate a LHN. To attach to a specific LHN, one or a combination of
the following may be used. A LHN configuration may be broadcast or
published. The WTRU may perform a LHN search. The LHN search may be
a manual search. The WTRU may perform a LHN cell selection.
[0100] The WTRU may search for its LHN to support LIPA services. A
network node or system may broadcast a LHN ID in a system
information block (SIB) from one or more cells that are within the
LHN. The WTRU may search for a LHN as an access point for its LIPA
access and/or SIPTO offload point, for example, for charging or any
other purpose. For example, LIPA-ALLOWED and/or SIPTO-ALLOWED flags
may be added to an SIB. The flags may indicate, for example, LIPA
and/or SIPTO capability of the Closed Subscriber Group (CSG) and/or
LHN to member WTRUs. Hybrid cells that may support LIPA and SIPTO
services for non-member WTRUs may broadcast a
LIPA-ALLOWED-NONMEMBER and/or a SIPTO-ALLOWED-NONMEMBER flag in its
SIB to indicate the LIPA and SIPTO capability of the CSG and/or LHN
to non-member WTRUs attempting to access the hybrid cell. For
example, these capability flags may be added to any message, for
example SIB-1. Table 1 shows an example of a message that includes
a LHN-id field, a SIPTO-ALLOWED field, a SIPTO-ALLOWED-NONMEMBER
field, a LIPA-ALLOWED field, and a LIPA-ALLOWED-NONMEMBER
field.
TABLE-US-00001 TABLE 1 SystemInformationBlockType1 ::= SEQUENCE {
cellAccessRelatedInfo SEQUENCE { plmn-IdentityList
PLMN-IdentityList, trackingAreaCode TrackingAreaCode, cellIdentity
CellIdentity, cellBarred ENUMERATED {barred, notBarred},
intraFreqReselection ENUMERATED {allowed, notAllowed},
csg-Indication BOOLEAN, csg-Identity CSG-Identity OPTIONAL -- Need
OR LHN-Id LHN-Identity OPTIONAL SIPTO-ALLOWED ENUMERATED {allowed,
notAllowed) OPTIONAL SIPTO-ALLOWED-NONMEMBER ENUMERATED {allowed,
notAllowed) OPTIONAL LIPA-ALLOWED ENUMERATED {allowed, notAllowed)
OPTIONAL LIPA-ALLOWED-NONMEMBER ENUMERATED {allowed, notAllowed)
OPTIONAL }, cellSelectionInfo SEQUENCE { q-RxLevMin Q-RxLevMin,
q-RxLevMinOffset INTEGER (1..8) OPTIONAL -- Need OP }, p-Max P-Max
OPTIONAL, -- Need OP freqBandIndicator INTEGER (1..64),
schedulingInfoList SchedulingInfoList, tdd-Config TDD-Config
OPTIONAL, -- Cond TDD si-WindowLength ENUMERATED { ms1, ms2, ms5,
ms10, ms15, ms20, ms40}, systemInfoValueTag INTEGER (0..31),
nonCriticalExtension SystemInformationBlockType1-v890-IEs OPTIONAL
}
[0101] A CSG may include H(e)NBs belonging to different LHNs. Also,
one LHN may span across multiple CSGs. A WTRU may search for a LHN
for SIPTO or LIPA service based on a "LHN List" provided to and/or
stored by the WTRU. A WTRU may only be allowed to use the SIPTO
and/or LIPA services (and other derivative services) over the LHNs
that have their LHN-Id included in this LHN list. The LHN List may
be used to manage the list of allowed LHN IDs, Operator LHN IDs,
and/or related restricted access information at a WTRU. This
information may be stored, for example, in the WTRU's Universal
Subscriber Identity Module (USIM) or in a non-volatile memory in
the WTRU, as well as at the operator's core network in, for
example, a Home Location Register (HLR)/Home Subscriber Server
(HSS). A WTRU may receive a message and/or indication from a cell
or H(e)NB that includes information related to a LHN. The message
and/or indication may also include other information, such as for
example, SIPTO/LIPA service information or identification
information. The WTRU may compare any of the received information
or indications with information stored in one or more LHN Lists
stored at the WTRU. The WTRU may perform cell selection or
reselection based on the comparison.
[0102] A WTRU may receive and/or maintain one or more CSG Lists.
For example, a WTRU may maintain a CSG white list or Allowed CSG
List that may include the CSG identities of CSGs that the WTRU
belongs to or for which access has been granted to the WTRU. Any of
the CSG Lists may include a list of allowed or previously visited
CSGs or cells. CSG Lists may be received by a WTRU, for example,
from upper layers or upon successful access to a CSG cell. One or
more CSG Lists may be stored in the WTRU, for example in a USIM or
a non-volatile memory. The WTRU may maintain and/or update the CST
Lists. A WTRU may receive a message and/or indication from a cell
or CSG that includes a CSG ID. The WTRU may compare the received
CSG ID with CSG IDs included in one or more CSG Lists stored at the
WTRU.The WTRU may perform cell selection or reselection based on
the comparison. The CSG List may also include or comprise a HNB or
H(e)NB List that includes a list of one or more HNBs or
H(e)NBs.
[0103] An LHN List may include sublists. For example, sublists may
include an "Allowed LHN List" and an "Operator's LHN List." As
referred to herein, the phrase "LHN List" may include the Allowed
LHN List and/or the Operator's LHN List as well as any other
sublist within the LHN List. The LHN operator, an end user, and/or
any operator may manage the Allowed LHN List. The Allowed LHN List
may include, for example, LHN membership granted by the LHN
operator and identified and/or verified by an end user. The Allowed
LHN List may also include the Operator's LHN List. The Allowed LHN
List may be used, for example, in a manual LHN search. The
Operator's LHN list may be managed by the service operator. The
Operator's LHN List may include, for example, the LHNs that a WTRU
is allowed to access. The Operator's LHN List may be used, for
example, for an automatic LHN search. Any of these lists may
include additional lists or elements.
[0104] FIG. 13 shows an example of an LHN List object. The LHN List
may be, for example, an LHN list with sublists such as the Allowed
LHN List and the Operator's LHN List. Similarly, the LHN List may
be any list or sublist described herein. The LHN List object shown
in FIG. 13 may therefore also represent an Allowed LHN List.
Referring to FIG. 13, AllowedLHNEntries may include a Public Land
Mobile Network ID (PLMN_ID) and/or LHN-entries. The LHN-entries may
include, but are not limited to, LHN_ID, NET_CAPABILITY, or
USER_CONSENT. The NET_CAPABILITY element may indicate, for example,
the LHN's capability to support SIPTO and/or LIPA service. Thus,
the NET_CAPABILITY element may include values such as, for example,
LIPA, SIPTO, or BOTH. The USER_CONSENT element may indicate, for
example, user consent for SIPTO and/or LIPA service for a
particular LHN. The USER_CONSENT element may include values such
as, for example, LIPA, SIPTO, or BOTH. The USER_CONSENT element may
also be defined, for example, per LHN, per APN, and/or per QoS.
OperatorLHNEntries may include a PLMN_ID and/or LHN-entries. The
LHN-entries may include, but are not limited to, LHN_ID,
NET_CAPABILITY, or USER_CONSENT. The NET_CAPABILITY element may
indicate, for example, the LHN's capability to support SIPTO and/or
LIPA service. Thus, the NET_CAPABILITY element may include values
such as, for example, LIPA, SIPTO, or BOTH. The USER_CONSENT
element may indicate, for example, user consent for SIPTO and/or
LIPA service for a particular LHN. The USER_CONSENT element may
include values such as, for example, LIPA, SIPTO, or BOTH. The
USER_CONSENT element may also be defined, for example, per LHN, per
APN, and/or per QoS. Any extensions (shown by, for example, the
"EXT" node) based on the nodes and leaf objects described herein
are understood to be within the contents of this example. For
example, the EXT node may include vendor-specific information. The
EXT node may include one or more sublists or sub-trees. One skilled
in the art will recognize that the names given are for purposes of
example only.
[0105] If a WTRU receives an Allowed LHN List Management Object
(MO) via, for example, the OMA DM Access including the Allowed LHN
List, the WTRU may update its Allowed LHN List. The Allowed LHN
List may be stored at the WTRU, for example, in a USIM or in a
non-volatile memory in the WTRU, as described above. If a WTRU
receives an Operator's LHN List Management Object (MO) via, for
example, the OMA DM Access including the Operator LHN List, it may
update the Operator LHN List stored in, for example, the USIM or
non-volatile memory.
[0106] A combined manual LHN and CSG cell selection procedure may
be performed. A WTRU may perform a manual LHN selection procedure,
for example during power-up, a user-intervention, or any other
programmed trigger, such as a WTRU entering a LHN proximity area.
In a manual LHN selection procedure, a WTRU, with an indication
from the NAS, may scan the available bands, find relevant or
available cells, and/or indicate a list of available LHNs to the
user along with, for example, associated CSG IDs and PLMNs.
Selection criteria for available LHNs may be sent to the WTRU, for
example, by an end user, via NAS signaling, or as defined in the
USIM. The criteria may include one or a combination of the
following. A LHN ID may be broadcasted by a suitable cell found by
the WTRU. A LHN ID may be broadcasted by a suitable cell found by
the WTRU, wherein the LHN ID is in one of the WTRU's LHN Lists, for
example the Allowed LHN and/or the Operator LHN list. A LHN ID may
broadcasted by a suitable cell found by the WTRU, wherein the LHN
ID is in the WTRU's Operator LHN List. A LHN ID may be broadcasted
by a suitable cell found by the WTRU, wherein the LHN ID is in the
WTRU's LHN List and the cell is either a hybrid cell or a closed
CSG cell whose CSG ID is included in the WTRU's CSG List, for
example either the Allowed CSG or the Operator CSG list. A LHN ID
may be broadcasted by a suitable cell found by the WTRU, wherein
the LHN ID is included in the WTRU's Operator LHN List and the cell
is either an hybrid cell or a closed CSG cell whose CSG ID is
included in the WTRU's CSG list, for example the Allowed CSG or the
Operator CSG list. A LHN ID may be broadcasted by a suitable cell
found by the WTRU, wherein the LHN ID is included in the WTRU's
Operator LHN List and the cell is either a hybrid cell or a private
CSG cell whose CSG ID is included in, for example, the WTRU's
Operator CSG List
[0107] For each entry in any list, a WTRU may indicate to a user
any or a combination of the following information. The WTRU may
indicate the LHN ID. Alternatively or additionally, the WTRU may
indicate the LHN group and/or whether or not the LHN is in the
Operator LHN List or the Allowed LHN List. Alternatively or
additionally, the WTRU may indicate the access cell type. The WTRU
may indicate whether the cell is a hybrid cell for which the WTRU
is not a member and/or whether the hybrid cell supports LHN access
for non-members. The WTRU may indicate the WTRU is a member of a
CSG cell. The WTRU may also indicate the CSG ID or the CSG ID group
and/or whether the CSG cell is included in an Operator CSG List or
an Allowed CSG List and/or whether the CSG cell is included in the
CSG white list. Alternatively or additionally, the WTRU may
indicate the SIPTO and/or LIPA capability of a cell.
[0108] A user may select a LHN from the indicated LHNs. If the WTRU
has a PDN connection for emergency bearer services, manual LHN
selection may not be performed. If the user makes a selection, the
WTRU may attempt to camp on a cell with the selected LHN identity
and may attempt to register from the cell to the associated
PLMN.
[0109] Access Stratum (AS) layer action may be used to support LHN
selection (for example, manual LHN selection). To support manual
LHN selection, the AS layer of the WTRU, for example, on the
request from the NAS, may scan some or all RF channels in the
configured bands according to the WTRU's capabilities to find
available LHN IDs. On each carrier, the WTRU may at least search
for the strongest cell, read system information of the strongest
cell, and/or report available LHN ID(s) together with the PLMN(s)
and/or CSG ID to the NAS. The search for available LHN IDs may be
stopped on request from the NAS.
[0110] A specific LHN search may also be supported in the AS layer
of the WTRU. If the NAS provides a LHN ID and/or CSG ID(s) to the
AS, the AS may search for an acceptable or a suitable cell
belonging to the selected LHN ID and CSG ID(s) and may camp on or
access that cell. If the NAS provides the LHN ID to the AS, the AS
may search for an acceptable or suitable cell that broadcasts the
selected LHN ID and/or belongs to a CSG group that is included in
the WTRU's CSG white list. The WTRU may perform registration via
the specific LHN cell.
[0111] If a user selects a LHN in a PLMN that is different from the
Registered PLMN (RPLMN), one or a combination of the following may
be performed. The WTRU may store a duplicate of the RPLMN and a
duplicate of the current PLMN selection mode. The WTRU may enter
into Manual mode for PLMN selection and may select the PLMN
corresponding to the LHN. The WTRU may attempt to register on the
selected LHN cell in the PLMN. If the registration fails or the
WTRU is no longer within the coverage of the LHN, the WTRU may
return to the stored duplicate PLMN selection mode and use the
stored duplicate value of RPLMN for further action. If the
registration succeeds, the WTRU may perform one or a combination of
the following, depending on the cell that the WTRU camps on. If the
camped cell is not included in the LHN list, the WTRU may add that
cell or LHN to the Allowed LHN List. If the camped cell is not
included in the CSG list, the WTRU may add the cell to the Allowed
CSG list. If the registration fails, one or more of the following
actions may be performed by the WTRU, for example, depending on the
return code. If the return code indicates that LHN access is not
allowed, the LHN ID may be removed from the Allowed LHN List. The
LHN ID may be added to the Forbidden LHN List. If the return code
indicates that the LHN is temporarily unavailable, the WTRU may
wait for a configured or predetermined time before allowing a
retry. LHNs in the Forbidden LHN List may also be indicated to the
user upon a LHN manual selection process. LHNs may be removed from
the list, for example, upon power off or during a successful manual
selection and registration.
[0112] LHN cell reselection may also be performed. If a WTRU does
not have a PDN connection to an L-GW that belongs to a LHN, the
WTRU may follow any cell reselection procedure. For an IDLE mode
WTRU that has or had a PDN connection to an L-GW belonging to a
LHN, special idle mode cell reselection may be used to keep the
SIPTO and/or LIPA PDN connection alive.
[0113] Cell selection from a LHN cell may be performed. If a WTRU
has or had a PDN connection to an L-GW belonging to a LHN and/or
the WTRU has camped on a suitable LHN cell (for example, the cell
belongs to the LHN), and if the WTRU detects another LHN cell which
ranks higher, the WTRU may reselect to the detected LHN cell. The
WTRU may optionally not reselect to a non-LHN cell regardless of
the rank of the cell. Alternatively or additionally, to reduce
interference, the targeted LHN cell may need to be the highest
ranked LHN cell on that frequency to be considered for reselection.
If the radio condition of the cell that WTRU is camped on is lost
or deteriorated, and if WTRU cannot find a suitable LHN cell, the
WTRU may reselect to any suitable cell. After the WTRU camps on the
non-LHN cell, the WTRU may maintain its local PDN connection (for
example, the PDN connection to the LHN) to allow the WTRU to go
back to a LHN cell. The WTRU may supply the L-GW information (for
example, L-GW@LN, L-GW@CN, or correlation-Id) via the new cell, for
example, to allow the supporting network to reroute the WTRU's
connectivity and/or traffic to the original L-GW.
[0114] Cell selection may be performed from a non-LHN cell. If a
WTRU has had a PDN connection to an L-GW belonging to a LHN and/or
if the WTRU is currently camped on a cell that does not belong to
the LHN, the WTRU may use an autonomous search function to detect
LHN cells. The LHN cells may include at least those allowed LHN
cells that the WTRU has previously visited on serving or
non-serving frequencies, including, for example, inter-RAT
frequencies. Any of the above may be performed alone or in
combination with normal cell reselection.
[0115] If the WTRU has detected one or more suitable LHN cells on
different frequencies, then the WTRU may reselect to one of the
detected cells based on the ranking of those cells and/or LHN ID
property. This may be performed, for example, irrespective of the
frequency priority of the cell the WTRU is currently camped on. If
the WTRU has detected a suitable LHN cell on the same frequency,
the WTRU may reselect to that cell. Alternatively or additionally,
the targeted LHN cell may be considered the highest ranked cell on
that frequency. For example, this may reduce interference.
[0116] LHN cell selection and/or reselection may be triggered by an
event. If a WTRU is paged from a LHN and the WTRU is currently
camped on a non-LHN cell or a different LHN cell, the network may
trigger the WTRU to search and reselect to a cell belonging to a
LHN. The network may also trigger the WTRU to search and reselect
to a cell belong to a LHN on behalf of a remote application or
based on SIPTO needs. The network may use, for example, a NAS or
RRC message to inform the WTRU of the LHN and/or the CSG group that
the network wants the WTRU to camp on or connect to. If the WTRU
receives the network message, the WTRU may release its RRC
connection and select or reselect to a cell according to network's
request. Optionally, certain events from the WTRU may also trigger
a LHN cell selection or reselection. This may include, for example,
a user's desire to do a local printing or any other local task.
[0117] A user preference may be defined and indicated by the WTRU.
For example, if a WTRU is camped on a LHN cell, it may indicate to
the network a preference for using LHN as its access point, for
example, to the internet and/or its preference to access the LHN
during an attach procedure or for a PDN connectivity procedure. A
user preference may be indicated, for example, in an ESM
INFORMATION RESPONSE message. A WTRU may include, for example, a
LHN ID in the ESM INFORMATION RESPONSE if the user prefers to
access a LHN network or access the APN via the LHN. The WTRU may
indicate its preference for a LIPA service by setting the LHN ID
and the APN to be the LHN's APN. If the WTRU prefers offloading its
traffic on the LHN, it may set the LHN ID to the LHN that the WTRU
prefers to use for offloading and may set the APN to the traffic
that it would like to offload. Table 2 shows an example of an ESM
INFORMATION RESPONSE that includes a LHN Identity information
element.
TABLE-US-00002 TABLE 2 ESM INFORMATION RESPONSE message content IEI
Information Element Type/Reference Presence Format Length Protocol
discriminator Protocol discriminator M V 1/2 9.2 EPS bearer
identity EPS bearer identity M V 1/2 9.3.2 Procedure transaction
identity Procedure transaction identity M V 1 9.4 ESM information
response Message type M V 1 message identity 9.8 28 Access point
name Access point name O TLV 3-102 9.9.4.1 27 Protocol
configuration options Protocol configuration options O TLV 3-253
9.9.4.11 LHN Identity LHN-ID O
[0118] Alternatively or additionally, a user preference may be
indicated in a PDN CONNECTIVITY REQUEST message. If a user prefers
to have a PDN connection to a LHN, the APN may be set to the APN of
the LHN and the LHN-Identity may be set to LHN-ID. If the user
prefers to establish a new PDN connection and prefers the new PDN
connection to be offloaded via the LHN, the APN may be set to the
APN the user prefers to establish the PDN connection with and/or
the LHN-identity may be set to the LHN-ID of the preferred offload
point. Table 3 shows an example of a PDN CONNECTIVITY REQUEST
message that includes a LHN Identity information element.
TABLE-US-00003 TABLE 3 PDN CONNECTIVITY REQUEST message content IEI
Information Element Type/Reference Presence Format Length Protocol
discriminator Protocol discriminator M V 1/2 9.2 EPS bearer
identity EPS bearer identity M V 1/2 9.3.2 Procedure transaction
identity Procedure transaction identity M V 1 9.4 PDN connectivity
request message Message type M V 1 identity 9.8 Request type
Request type M V 1/2 9.9.4.14 PDN type PDN type M V 1/2 9.9.4.10 D-
ESM information transfer flag ESM information transfer flag O TV 1
9.9.4.5 28 Access point name Access point name O TLV 3-102 9.9.4.1
27 Protocol configuration options Protocol configuration options O
TLV 3-253 9.9.4.11 LHN Identity LHN-ID O
[0119] A user's network preference may also be included in an
ATTACH REQUEST. If the LHN-ID is present in the ATTACH REQUEST
message, the network may establish the default PDN connection via
an L-GW of the specified LHN. Table 4 shows an example of an ATTACH
REQUEST message that includes a LHN Identity information
element.
TABLE-US-00004 TABLE 4 ATTACH REQUEST message content IEI
Information Element Type/Reference Presence Format Length Protocol
discriminator Protocol discriminator M V 1/2 9.2 Security header
type Security header type M V 1/2 9.3.1 Attach request message
identity Message type M V 1 9.8 EPS attach type EPS attach type M V
1/2 9.9.3.11 NAS key set identifier NAS key set identifier M V 1/2
9.9.3.21 EPS mobile identity EPS mobile identity M LV 5-12 9.9.3.12
UE network capability UE network capability M LV 3-14 9.9.3.34 ESM
message container ESM message container M LV-E 5-n 9.9.3.15 19 Old
P-TMSI signature P-TMSI signature O TV 4 10.5.5.8 50 Additional
GUTI EPS mobile identity O TLV 13 9.9.3.12 52 Last visited
registered TAI Tracking area identity O TV 6 9.9.3.32 5C DRX
parameter DRX parameter O TV 3 9.9.3.8 31 MS network capability MS
network capability O TLV 4-10 9.9.3.20 13 Old location area
identification Location area identification O TV 6 9.9.2.2 .sup. 9-
TMSI status TMSI status O TV 1 9.9.3.31 11 Mobile station classmark
2 Mobile station classmark 2 O TLV 5 9.9.2.4 20 Mobile station
classmark 3 Mobile station classmark 3 O TLV 2-34 9.9.2.5 40
Supported Codecs Supported Codec List O TLV 5-n 9.9.2.10 F-
Additional update type Additional update type O TV 1 9.9.3.0B 5D
Voice domain preference and UE's Voice domain preference and UE's
usage O TLV 3 usage setting setting 9.9.3.44 D- Device properties
Device properties O TV 1 9.9.2.0A LHN-Identity LHN-ID O
[0120] The information element "Local Home Network" may be in the
form of a LHN-Identifier or in any other form. If one H(e)NB may
only belong to one LHN, the LHN-ID may be implicitly specified if a
WTRU indicates a preference for SIPTO service. A WTRU may also
include a Preferred_SIPTO_Point in a PDN CONNECTIVITY REQUEST
message for a new PDN connection. Alternatively or additionally, a
Preferred_SIPTO_Point may be included in an ATTACH COMPLETE
message. The LHN-ID for the local home network for which the WTRU
is requesting connectivity may be added to an ATTACH REQUEST
message or a PDN CONNECTIVITY REQUEST message sent, for example,
with the ATTACH REQUEST. The LHN-ID may be included as an
information element.
[0121] SIPTO and/or LIPA service continuity may be supported. The
SIPTO/LIPA service continuity may be supported outside the LHN
cells in the Service Continuity Area (SCA). Providing WTRUs and/or
the network with SIPTO/LIPA service continuity information and
where it may be maintained may help make the cell reselection
and/or handover decisions in idle mode and/or in connected mode,
respectively. The Service Continuity Area may be defined by one or
more of the following items in any combination. For example, the
SCA may be defined as a list of cell IDs, a list of CSG IDs, a list
of area IDs, such as, for example, Tracking Area Identities (TAIs),
and/or a list of PLMN IDs. A WTRU may acquire the SCA either by
reading a system information broadcast or by being informed via
messages, such as for example, dedicated RRC messages or NAS
messages. Alternatively or additionally, the SCA information
provided to a WTRU may include information related to only nearby
relevant neighboring cells within the reach of a WTRU for cell
reselection or a handover measurement scan range, either adjacent
or close to the current cell. This may conserver signaling space.
To maintain SIPTO/LIPA service continuity, WTRUs in Idle mode may
use the SCA information to facilitate the cell reselection.
Alternatively or additionally, WTRUs in connected mode may use the
SCA information for mobility measurements.
[0122] SIPTO/LIPA service continuity may be maintained in Idle
mode. A WTRU that does not have a PDN connection to an L-GW
belonging to a LHN may follow normal cell reselection procedures.
An IDLE mode WTRU that has had a PDN connection to an L-GW
belonging to a LHN may use special idle mode cell reselection to
keep the SIPTO/LIPA PDN connection alive.
[0123] Cell selection may be performed from a cell in the SCA. If a
WTRU has had a PDN connection to an L-GW belonging to a LHN and/or
the WTRU is camped on a suitable SCA cell (for example, the cell
supports SIPTO/LIPA service continuity to the LHN) and/or if the
WTRU detects another SCA cell that ranks higher than the current
cell, the WTRU may reselect to the detected SCA cell. The WTRU may
not reselect to a non-SCA cell regardless of how highly that cell
is ranked. Alternatively or additionally, reselection candidacy may
include a rule such that the targeted SCA cell may need to be the
highest ranked cell on that frequency. This may reduce
interference. If the radio condition of the cell that the WTRU is
camped on is lost or deteriorated and/or if the WTRU cannot find a
suitable SCA cell, the WTRU may reselect to any suitable cell. If
the WTRU camps on the non-SCA cell, the WTRU may maintain its local
PDN connection (for example, a PDN connection to the LHN). This may
allow the WTRU to go back to SCA coverage. Alternatively or
additionally, the WTRU may supply the L-GW information (for
example, L-GW@LN, L-GW@CN, or correlation-Id) via the new cell to
allow the network to reroute the WTRU's connectivity and/or traffic
to the original L-GW.
[0124] Cell selection may be performed from a cell outside the SCA.
For example, if a WTRU has had a PDN connection to an L-GW
belonging to a LHN and if the WTRU is currently camped on a cell
that is not in SCA coverage, the WTRU may use an autonomous search
function to detect at least previously visited and/or allowed SCA
cells on serving or non-serving frequencies, which may include
inter-RAT frequencies. This may be performed alternatively or in
addition to normal cell reselection.
[0125] If the WTRU has detected one or more suitable SCA cells on
different frequencies, the WTRU may reselect to one of the detected
cells irrespective of the frequency priority of the cell that the
WTRU is currently camped on. To reduce interference, further
restriction may be used if the concerned LHN cell is the highest
ranked cell on that frequency. If the WTRU detects a suitable SCA
cell on the same frequency, it shall reselect to this cell. To
reduce interference, further restriction may be applied if the
concerned SCA cell is the higher ranked cell than the current cell
on that frequency.
[0126] WTRU-requested LHN PDN Connectivity may be performed without
using an IMSI and/or MSISDN. To protect user privacy, if a WTRU
requests LHN PDN Connectivity, the MME/Network may not include the
WTRU's IMSI or MSISDN in the corresponding message (for example, a
CREATE SESSION REQUEST message) sent to the L-GW of the requested
LHN. The MME may request a temporary IMSI (T_IMSI) and/or a
temporary MSISDN (T_MSISDN) from a HSS and may use the T_IMSI and
T_MSISDN in the message for creating PDN connectivity with an L-GW.
The HSS may store the T_IMSI and/or T_MSISDN. The stored T_IMSI
and/or T_MSISDN may be released if the LHN PDN Connectivity is
released.
[0127] Connectivity may be restored between the new HeNB and the
L-GW after radio link failure (RLF). A WTRU may acquire the L-GW's
correlation ID, which may include, for example, the L-GW@CN, the
L-GW@LN, and/or Tunnel Endpoint Identifiers (TEIDs), during an
attach procedure. This may be acquired via, for example, the ATTACH
ACCEPT message if the WTRU attached to an L-GW. The L-GW's
correlation ID may also be acquired during the PDN CONNECTIVITY
REQUEST procedure, via for example, a PDN Connectivity Accept
message if the WTRU activates a PDN connection at L-GW. During a
NAS signaling connection recovery procedure, a WTRU may provide the
L-GW's correlation ID (and optionally the L-GW@CN) to the serving
eNB and the serving eNB may restore the S-XX interface towards the
L-GW without going through the Core Network.
[0128] A WTRU may want to register to the network via an ATTACH
REQUEST with SIPTO and/or LIPA capabilities enabled with the
support of other CN PLMN services. The WTRU may be interested in
the LHN services, but perhaps not any PLMN services (for example,
the location services or MBMS services) except for control plane
signaling. The WTRU may transmit an ATTACH REQUEST to the network
with a type indicating, for example, "LHN Service only" and the
LHN-ID of the LHN.
[0129] A WTRU's ATTACH REQUEST for LHN access may be rejected by
the network for various reasons. A rejection may be caused by the
user's related subscription or may be related in the MME/L-GW
interaction process if the L-GW fails to honor the MME request due
to, for example, local security issues. This may include scenarios
in which the L-GW may have certain autonomous operational
restrictions to WTRUs or to a particular WTRU. This may include,
for example, a downgraded access privilege level. The L-GW
rejection or grant with restriction may result in an MME response
(such as an ATTACH REJECT) to the WTRU ATTACH REQUEST. The
non-successful ATTACH results may be indicated to the WTRU in the
return code, for example, by indicating "Access to the L-GW
denied," "Access to the L-GW expired," "L-GW is temporarily
unavailable," or the like. In the case of access denial or
expiration, the LHN-Id may need to be removed from the Allowed LHN
List. If the L-GW is unavailable, the WTRU may refrain from
accessing the same L-GW for a configured/predetermined time
period.
[0130] A SIPTO/LIPA-connected WTRU may require a minimum level of
service integrity. If there is an active local access, for example
a LIPA service, that is ongoing and a WTRU-initiated detach is
started, the Detach procedure may need to wait (for example, with a
timer) for the completion of the ongoing local access. If the timer
expires, the user of the WTRU may be alerted and may be prompted to
wait or stop the local access and continue the Detach procedure.
The MME may Detach and re-attach the WTRU if one or more of the
following conditions are true. The MME may Detach and re-attach if
the L-GW is out of service and the WTRU has attached to both PLMN
and LIPA services. In this example, the MME may re-attach the WTRU
to a P-GW for PLMN service until the L-GW is recovered.
Alternatively or additionally, the MME may detach and re-attach the
WTRU to the L-GW if the L-GW is recovered.
[0131] The network may trigger SIPTO and/or LIPA with a
detach/reattach procedure. To support network-triggered SIPTO or
LIPA bearer relocation from a core network to a LHN and/or L-GW, an
indication may be included in a DETACH REQUEST message. If the
detach type is, for example, "re-attach required," the network may
specify a "Reattach Target." The Reattach Target may be one or more
of the following: the current cell; a cell ID; a group of Cell IDs;
a LHN ID; a CSG ID; and/or a group of CSG IDs. Table 5 shows an
example of a DETACH REQUEST message that includes a Reattach Target
information element.
TABLE-US-00005 TABLE 5 Table DETACH REQUEST message content IEI
Information Element Type/Reference Presence Format Length Protocol
discriminator Protocol discriminator M V 1/2 9.2 Security header
type Security header type M V 1/2 9.3.1 Detach request message
identity Message type M V 1 9.8 Detach type Detach type M V 1/2
9.9.3.7 Spare half octet Spare half octet M V 1/2 9.9.2.9 53 EMM
cause EMM cause O TV 2 9.9.3.9 Reattach Target
[0132] If a WTRU receives a DETACH REQUEST with a detach type of
re-attach required that includes the Reattach Target IE, the WTRU
may attempt to search for cell(s) whose identity or identities are
indicated in the Reattach Target IE. The WTRU may perform a
(re)attach procedure after the WTRU has selected a cell belonging
to the Reattach Target.
[0133] RAN sharing and EPLMN support may be provided with LHNs. In
one example, traffic and signaling from multiple LHNs or L-GWs may
be transmitted or received through a common cell. In another
example, a cell may broadcast a list of supported LHN IDs. If
multiple LHNs are broadcasting information, additional flags may be
provided in, for example, SIB1 as described above. The flags may be
in the form of a list and the number of entries may match the
number of supported LHNs. For example, if a WTRU selects a cell and
initiates a connection (for example, at the RRC level or NAS level)
toward the network, the WTRU may indicate to the network the
selected LHN ID or any other LHN and/or L-GW related attribute to
help the network correlate the WTRU to the LHN or the L-GW. In
another example, the H(e)NB may store the LHN ID as part of the
WTRU context information and may use this information to correctly
route signaling related to this WTRU to the appropriate LHN or
L-GW. This may be performed upon reception of, for example, the RRC
CONNECTION REQUEST message or any other equivalent message. The
H(e)NB may use the LHN information stored in the WTRU context to
identify the correct LHN or L-GW for which to establish the bearers
for the WTRU.
[0134] In another example, the WTRU may use the LHN ID or any other
attribute or related flag to indicate the WTRU's preference or need
to establish a SIPTO and/or LIPA connection, or to switch the
existing PDN connections (for example, a SIPTO PDN connection) to
the L-GW. These may be performed upon detection of a LHN or L-GW
that the WTRU belongs to. In another example, the WTRU may report
its LHN Identification or any other related information upon
configuration of the network. Alternatively or additionally, the
WTRU may autonomously report the LHN Identification or any other
related information.
[0135] In another example, the WTRU may perform access control
taking into account the LHN membership and/or the CSG membership.
In one example, the WTRU is a member and may access the cell if the
WTRU is a member of the CSG and the LHN, meaning that the WTRU has
this LHN associated with the CSG in the WTRU's white list. In
another example, the WTRU may be a member and may access the cell
if the WTRU has the association of the CSG, the PLMN (or equivalent
PLMN), and/or the LHN in the WTRU's white list. The operator may
have control over the list of the PLMNs in the white list and the
associated CSGs. The host party may have control over the
associated LHNs. The LHN list may be uploaded to the operator as
part of the LHN or L-GW registration procedure. In another example,
access to SIPTO/LIPA may be controlled at the WTRU or the network
based on the cell's CSG ID, one or several of the broadcasted LHN
IDs, or the broadcasted PLMN ID being on the WTRU's white list.
[0136] The examples described above, while presented under the
scenario of RAN sharing or femto network sharing by multiple LHNs
or L-GWs are not to be limited to only such scenarios and are
applicable to any other example or embodiment described herein and
for use with any other SIPTO or LIPA service.
[0137] L-GW registration and/or multi-H(e)NB registration may be
performed. As the L-GW is powered up, there may be a need for the
L-GW to inform the H(e)NB-GW that the L-GW is now available at a
particular IP address. The L-GW may also need to enable the HNB-GW
to provide service and core network connectivity for the L-GW and
possibly to the H(e)NBs connected to the L-GW. Because the L-GW may
be connected to multiple H(e)NBs, the L-GW may act as an H(e)NB
aggregator in some instances. For example, if an L-GW shuts down
and then is powered up or turned on, the individual H(e)NB under
the L-GW may need to be re-registered to the core network (via for
example the H(e)NB-GW) or the L-GW may act as an aggregator and
register its H(e)NB with the H(e)NB-GW. Each H(e)NB may maintain an
individual Iuh connection with the H(e)NB-GW or Iuh aggregation may
occur between the L-GW and the H(e)NB-GW.
[0138] The L-GW Registration Procedure may allow the L-GW to
register with the H(e)NB-GW or another node in the core network
such as, for example, the MME, the S-GW, or the SGSN. This may
enable the H(e)NB-GW to provide service and core network
connectivity for the HNB. If supported and configured, this may
also enable Iurh connectivity via the H(e)NB-GW. This procedure may
be triggered after the Iuh, Sxx, or S1 signaling transport has been
successfully established and may optionally be the first procedure
triggered after establishment. For Iuh, Sxx, or S1 signaling
transport, there may be one signaling transport instance between
the L-GW and the core network in support of all attached H(e)NBs.
In another example, there may be a one-to-one mapping between the
signaling transport bearer from any given H(e)NB to the L-GW, and
from the L-GW to the core network (for example, the H(e)NB-GW).
[0139] FIG. 14 shows an example call-flow diagram 1400 for a
successful L-GW register procedure. An L-GW 1405 and an H(e)NB-GW
1410 are shown, although any other nodes or elements may be used in
the procedure. The L-GW 1405 may send an L-GW REGISTER REQUEST 1420
to the H(e)NB-GW 1410. The L-GW REGISTER REQUEST 1420 may be sent
by the L-GW 1405 if the L-GW 1405 needs to commence operations
and/or requires service from a core network (not shown) via, for
example, the H(e)NB-GW 1410. The L-GW 1405 may provide its LHN ID
and/or transport layer address during the registration process and
the LHN ID and/or transport layer address may be included in the
L-GW REGISTER REQUEST 1420. The L-GW 1405 may provide a capability,
such as for example, support for SIPTO and/or LIPA services, or any
restrictions with respect to SIPTO and/or LIPA services. The L-GW
1405 may include any capability information in the L-GW REGISTER
REQUEST 1420.
[0140] An HNB (not shown) may provide a list of attached H(e)NBs
and/or the operational parameters included in an HNB REGISTRATION
REQUEST message. As described in the examples for FIGS. 14-17, an
HNB REGISTRATION REQUEST may be used instead of or in addition to
an L-GW REGISTER REQUEST. An HNB and/or an L-GW may register with a
core network and/or HNB-GW to provide services to a WTRU within the
HNB and/or L-GW. For example, an HNB may register directly with the
core network/HNB-GW and/or the L-GW may register one or more HNBs.
Thus, the L-GW may include any features of the HNB REGISTER REQUEST
in the L-GW REGISTER REQUEST or any other L-GW message described
herein, and vice versa. If the L-GW 1405 supports direct interface
relocation to other L-GWs (not shown), the L-GW 1405 may provide
the direct interface signaling Transport Network Layer (TNL)
Address IE to the core network (via H(e)NB-GW 1410) in, for
example, the L-GW REGISTER REQUEST 1420.
[0141] If the registration is successful, the core network (via
H(e)NB-GW 1410) may respond by transmitting an L-GW REGISTER ACCEPT
1430 message. The L-GW REGISTER ACCEPT 1430 message may indicate
acceptance and registration. The acceptance and/or registration may
include configurations for SIPTO and/or LIPA support. If a list of
attached H(e)NBs is included in the L-GW REGISTER ACCEPT 1430
message (or, for example, an HNB REGISTRATION REQUEST message), the
core network may indicate the registration result (for example,
accept or reject) for each of the attached H(e)NBs in the L-GW
REGISTER REQUEST 1420 message. If the direct interface signaling
TNL Address IE is included in the L-GW REGISTER ACCEPT 1430
message, the L-GW 1405 may, if supported, establish a transport
layer session to the indicated address to support direct
connectivity via the H(e)NB-GW 1410. If the H(e)NB-GW 1410 is
capable of de-multiplexing, then a MuxPortNumber IE may be included
in the L-GW REGISTER ACCEPT 1430 message.
[0142] One skilled in the art will recognize that the messages
described above with respect to FIG. 14 may be any type of message
and the information included in each of the messages may be
included in any type of message. Similarly, the messages may be
transmitted in any order and not only in the order described in the
example above.
[0143] FIG. 15 shows an example call-flow diagram 1500 for an
unsuccessful L-GW register procedure. An L-GW 1505 and an H(e)NB-GW
1510 are shown, although any other nodes or elements may be used in
the procedure. The L-GW 1505 may send an L-GW REGISTER REQUEST 1520
to the H(e)NB-GW 1510. The L-GW REGISTER REQUEST 1520 may be sent
by the L-GW 1505 if the L-GW 1505 needs to commence operations
and/or requires service from a core network (not shown) via, for
example, the H(e)NB-GW 1510. The L-GW 1505 may provide its LHN ID
and/or transport layer address during the registration process and
the LHN ID and/or transport layer address may be included in the
L-GW REGISTER REQUEST 1520. The L-GW 1505 may provide a capability,
such as for example, support for SIPTO and/or LIPA services, or any
restrictions with respect to SIPTO and/or LIPA services. The L-GW
1505 may include any capability information in the L-GW REGISTER
REQUEST 1520.
[0144] An HNB (not shown) may provide a list of attached H(e)NBs
and/or the operational parameters included in an HNB REGISTRATION
REQUEST message. If the L-GW 1505 supports direct interface
relocation to other L-GWs (not shown), the L-GW 1505 may provide
the direct interface signaling TNL Address IE to the core network
(via H(e)NB-GW 1510) in, for example, the L-GW REGISTER REQUEST
1520.
[0145] If the registration is unsuccessful, the core network (via
H(e)NB-GW 1510) may respond by transmitting an L-GW REGISTER REJECT
1530 message (or an HNB REGISTER REJECT message) to the L-GW 1505.
A typical cause value for unsuccessful registration may include
radio network layer causes, such as for example, unauthorized
location, unauthorized attached HNB, overload, L-GW parameter
mismatch (for example, a capability mismatch considering the
service level agreement between the operator and the host party of
the L-GW), or an unspecified cause. Any of these causes may be
included in the L-GW REGISTER REJECT 1530 message as a cause IE.
For example, if the cause IE is set to "overload," the HNB may not
retry registration to the same H(e)NB-GW 1510 for at least the
duration indicated by, for example, a Backoff Timer IE.
[0146] One skilled in the art will recognize that the messages
described above with respect to FIG. 15 may be any type of message
and the information included in each of the messages may be
included in any type of message. Similarly, the messages may be
transmitted in any order and not only in the order described in the
example above.
[0147] If a core network (via for example, an H(e)NB-GW) receives a
duplicate L-GW REGISTER REQUEST message (for example, for an
already registered L-GW identified by the same unique L-GW identity
or LHN identity), the new L-GW REGISTER REQUEST message may
override the existing registration. The handling of the new L-GW
REGISTER REQUEST message may be performed according to the examples
described above.
[0148] FIG. 16 shows an example call-flow diagram 1600 for an L-GW
deregistration procedure that originates at the L-GW. An L-GW 1605
and an H(e)NB-GW 1610 are shown, although any other nodes or
elements may be used in the procedure. The L-GW 1605 may determine
that it needs to terminate operations with the H(e)NB-GW 1610. The
L-GW 1605 may optionally terminate connections with attached
H(e)NBs before initiating termination with the H(e)NB-GW 1610. The
L-GW 1605 may transmit an L-GW DE-REGISTER 1620 message to the
H(e)NB-GW 1610. If the core network (not shown) receives the L-GW
DE-REGISTER 1620 message (via the H(e)NB-GW 1610), the core network
may clear all related resources associated with the L-GW 1605.
Cause values for the de-register process may include radio network
layer causes, such as for example, normal or unspecified. The cause
values may be included in, for example, the L-GW DE-REGISTER 1620
message.
[0149] One skilled in the art will recognize that the messages
described above with respect to FIG. 16 may be any type of message
and the information included in each of the messages may be
included in any type of message. Similarly, the messages may be
transmitted in any order and not only in the order described in the
example above.
[0150] FIG. 17 shows an example call-flow diagram 1700 for an L-GW
deregistration procedure that originates at the H(e)NB-GW. An L-GW
1705 and an H(e)NB-GW 1710 are shown, although any other nodes or
elements may be used in the procedure, such as those shown in FIGS.
7-12. The core network (not shown) (via the H(e)NB-GW 1710) may
determine that it needs to terminate operations with the L-GW 1705.
The core network (via the H(e)NB-GW 1710) may transmit an L-GW
DE-REGISTER 1720 message to the L-GW 1705. The core network may
clear all related resources associated with the L-GW 1705. Cause
values for the de-register process may include radio network layer
causes, such as for example, overload or unspecified causes. The
cause values may be included in IEs in, for example, the L-GW
DE-REGISTER 1720 message. If the cause IE in the L-GW DE-REGISTER
1720 message is set to "overload," the L-GW may not retry
registration to the same H(e)NB-GW 1710 for at least the duration
indicated by, for example, a Backoff Timer IE.
[0151] One skilled in the art will recognize that the messages
described above with respect to FIG. 17 may be any type of message
and the information included in each of the messages may be
included in any type of message. Similarly, the messages may be
transmitted in any order and not only in the order described in the
example above.
[0152] Although features and elements are described above in
particular combinations, one of ordinary skill in the art will
appreciate that each feature or element may be used alone or in
combination with any of the other features and elements. In
addition, the embodiments described herein may be implemented in a
computer program, software, or firmware incorporated in a
computer-readable medium for execution by a computer or processor.
Examples of computer-readable media include electronic signals,
(transmitted over wired or wireless connections), and
computer-readable storage media. Examples of computer-readable
storage media include, but are not limited to, a read only memory
(ROM), a random access memory (RAM), a register, a cache memory, a
semiconductor memory device, a magnetic media, (e.g., an internal
hard disc or a removable disc), a magneto-optical media, and an
optical media such as a compact disc (CD) or a digital versatile
disc (DVD). A processor in association with software may be used to
implement a radio frequency transceiver for use in a WTRU, UE,
terminal, base station, Node-B, eNB, HNB, HeNB, AP, RNC, wireless
router or any host computer. Although examples are described with
respect to a WTRU and/or a user, one of ordinary skill in the art
will appreciate that either the WTRU or a user may perform the
features or elements described in the examples.
* * * * *