U.S. patent application number 13/508557 was filed with the patent office on 2012-09-06 for network device in a communication network and method for providing communications traffic breakout.
This patent application is currently assigned to NOKIA SIEMENS NETWORKS OY. Invention is credited to Wolfgang Hahn, Matti Einari Laitila, Seppo Ilmari Vesterinen.
Application Number | 20120224536 13/508557 |
Document ID | / |
Family ID | 41571416 |
Filed Date | 2012-09-06 |
United States Patent
Application |
20120224536 |
Kind Code |
A1 |
Hahn; Wolfgang ; et
al. |
September 6, 2012 |
NETWORK DEVICE IN A COMMUNICATION NETWORK AND METHOD FOR PROVIDING
COMMUNICATIONS TRAFFIC BREAKOUT
Abstract
According to an exemplary embodiment of the invention a network
device may be provided which may comprise a receiving unit, a
sending unit and an evaluating unit. It may be foreseen that the
receiving unit may be adapted to receive a trigger signal for
preparing a breakout of a plurality of packets, wherein the
plurality of packets may comprise at least one packet from a first
source and at least one packet from a second source and wherein the
evaluating unit may be adapted to evaluate the trigger signal.
Moreover, the evaluation unit may be adapted to evaluate packets
from a first source and packets from a second source and the
evaluation unit may be adapted to distinguish packets from the
first source from packets from the second source.
Inventors: |
Hahn; Wolfgang; (Bergfelde,
DE) ; Vesterinen; Seppo Ilmari; (Oulunsalo, FI)
; Laitila; Matti Einari; (Oulu, FI) |
Assignee: |
NOKIA SIEMENS NETWORKS OY
Espoo
FI
|
Family ID: |
41571416 |
Appl. No.: |
13/508557 |
Filed: |
November 10, 2009 |
PCT Filed: |
November 10, 2009 |
PCT NO: |
PCT/EP09/64910 |
371 Date: |
May 8, 2012 |
Current U.S.
Class: |
370/328 ;
370/392; 370/401 |
Current CPC
Class: |
H04L 45/72 20130101;
H04W 88/16 20130101; H04W 76/20 20180201; H04L 47/10 20130101; H04L
45/00 20130101 |
Class at
Publication: |
370/328 ;
370/401; 370/392 |
International
Class: |
H04L 12/56 20060101
H04L012/56; H04W 40/00 20090101 H04W040/00 |
Claims
1. A network device comprising a receiving unit, a sending unit, an
evaluating unit, wherein the receiving unit is adapted to receive a
trigger signal for preparing a breakout of a plurality of packets,
wherein the plurality of packets comprise at least one packet from
a first source and at least one packet from a second source,
wherein the evaluating unit is adapted to evaluate the trigger
signal, wherein the evaluation unit is adapted to evaluate packets
from the first source and packets from the second source, and
wherein the evaluation unit is adapted to distinguish packets from
the first source from packets from the second source.
2. Network device according to claim 1, wherein the network device
is adapted to analyzing the plurality of packets received via a
bearer service, forwarding packets from the first source to a
server via the bearer service, and breaking out, from the bearer
service, packets from the second source and routing the packets
from the second source to a separate network.
3. Network device according to claim 1, wherein the network device
is at least one of the group of network devices consisting of an
UE, a MME, a S-GW, a P-GW, a S-/P-GW, a network node, an eNodeB, a
HeNodeB, an eNB/L-GW, a HeNB/L-GW and a L-GW.
4. Network device according to claim 1, wherein the network device
is adapted to use a first IP address for the first source and a
second IP address for the second source and wherein the network
device is adapted to generate the second IP address.
5. Network device according to claim 1, wherein the breakout is UE
initiated.
6. Network device according to claim 1, wherein the breakout is
network initiated.
7. Network device according to claim 1, wherein the trigger signal
is at least one of the group of signals consisting of a NAS
message, a detection of a SIPO supported service in the network and
a movement of an UE.
8. Network device according to claim 1, wherein the network device
comprises a local interface.
9. Network device according to claim 1, wherein the network device
comprises a BOGW-function.
10. Network device according to claim 9, wherein the BOGW-function
is at least one of the group of functions consisting of routing of
packets, routing of uplink packets, collecting of UL statistics,
collecting of DL statistics, gateway bridging, downlink packet
buffering, ECM-IDLE mode downlink packet buffering, initiating of
network triggered service request procedure, assisting in UE
IP-address allocation for accessing a home based network,
DHCPv4-functions, DHCPv6 functions, providing server
functionalities, providing relay functionalities, providing client
functionalities, providing local IP address signaling in control
messages, providing local IP address signaling in control messages,
such as GTP and NAS and providing downlink local packets in a
tunnel, especially providing an inclusion of downlink local packets
in a GTP tunnel at an S1-U interface.
11. Network device according to claim 1, wherein the network device
is adapted to support a breakout service based on a received
information, which information is at least one of the group of
information consisting of a UE Requested PDN Connectivity, a UE
Triggered Service Request, a UE Requested Bearer Resource
Modification, a Dedicated Bearer Activation, a Bearer Modification,
a Network Triggered Service Request, a S1 Release procedure, a
UE-initiated Detach procedure for E-UTRAN, a MME Initiated
Dedicated Bearer Deactivation, a UE Requested PDN disconnection and
a Create/Update (Default) Bearer Request.
12. Network device according to claim 1, wherein the network device
is adapted to provide a local IP address.
13. A method for providing communications traffic breakout
comprising: receiving a trigger signal for preparing a breakout of
a plurality of packets, wherein the plurality of packets comprise
at least one packet from a first source and one packet from a
second source, evaluating the trigger signal, evaluating packets
from a first source and from a second source, distinguishing
packets from the first source from packets from the second
source.
14. Network device according to claim 13, wherein the method
further comprising: analyzing the packets received via a bearer
service, forwarding packets from the first source to a server via
the bearer service, and breaking out, from the bearer service,
packets from the second source and routing the packets from the
second source to a separate network.
15. Computer readable medium, comprising program code, which
program code when being executed on a processor is adapted to carry
out the method according to claim 13.
Description
TECHNICAL FIELD
[0001] Embodiments of the present invention relate generally to
mobile communications, and, more particularly, relate to a network
device and a method for communications traffic breakout.
BACKGROUND
[0002] The modern communications era has brought about a tremendous
expansion of wireline and wireless networks. Various types of
networking technologies have been developed resulting in
unprecedented expansion of computer networks, television networks,
telephony networks, and the like, fueled by consumer demand.
Wireless and mobile networking technologies have addressed related
consumer demands, while providing more flexibility and immediacy of
information transfer.
[0003] Current and future networking technologies continue to
facilitate ease of information transfer and convenience to users by
expanding the capabilities of mobile electronic devices and other
computing devices. The functionality of mobile communications
devices continues to expand and, as a result, mobile communications
devices have become ubiquitous in both business and personal
settings. As the functionally of mobile communications devices and
the ease of information transfer continues to increase, users
continue to demand more functionality that allows the users to
quickly find and interact with more data in unique ways.
[0004] Some users expect mobile communication devices to be as
powerful as conventional computing systems and offer the same types
and levels of network connectivity in a wireless package. Many
users desire streamlined connections with both local area networks
(LANs) and other networks, such as the Internet, that area
available via through a communications core network for mobile
communications.
[0005] There may be a need to provide an access simultaneously to a
first network and to a second network.
BRIEF SUMMARY
[0006] Various example methods and devices of the present invention
are described herein for routing packets, received via a bearer
service, to a server, such as server connected to a core network,
or breaking out packets from the bearer service and routing packets
to a separate network, such as a LAN.
[0007] According to an exemplary embodiment of the invention a
network device may be provided which may comprise a receiving unit,
a sending unit and an evaluating unit. It may be foreseen that the
receiving unit may be adapted to receive a trigger signal for
preparing a breakout of a plurality of packets, wherein the
plurality of packets may comprise at least one packet originating
from a first source and at least one packet originating from a
second source and wherein the evaluating unit may be adapted to
evaluate the trigger signal. Moreover, the evaluation unit may be
adapted to evaluate packets originating from a first source and
packets originating from a second source and the evaluation unit
may be adapted to distinguish packets originating from the first
source from packets originating from the second source.
[0008] The network device may be a network apparatus, which may
receive and send packets from different sources, respectively. The
packets may be IP packets, which may comprise a source IP address,
which may be utilized in order to prepare a breakout.
[0009] According an exemplary embodiment of the invention the
network device may be adapted to analyzing the packets received via
a bearer service, forwarding packets from the first source to a
server via the bearer service, and breaking out, from the bearer
service, packets from the second source and routing the packets
from the second source to a separate network.
[0010] According to an exemplary embodiment of the invention the
breakout may be UE initiated. The initiation may be provided by a
trigger event or a trigger signal. The UE may move into a cell
where a breakout service may be provided. Thus, the movement of the
UE may initiate a breakout in that cell.
[0011] According to an exemplary embodiment of the invention the
breakout may be network initiated.
[0012] This may be possible by a receiving information or an
information message sent by a network device installed within the
network, for example within the EPC or a operator network.
[0013] According to an exemplary embodiment of the invention the
network device may comprise a local interface.
[0014] An interface may be a local interface SGi interface to a
S-GW. Another interface may be a local interface L-SGi (Local SGi)
to a local IP network.
[0015] According to an exemplary embodiment of the invention the
network device may comprise at least one BOGW-function
(BOGW=Breakout-Gateway), which BOGW-function may be for example
routing of packets, routing of uplink packets, collecting of UL
statistics (UL=uplink), collecting of DL (downlink) statistics,
gateway bridging, downlink packet buffering, ECM-IDLE mode downlink
packet buffering, initiating of network triggered service request
procedure, assisting in UE IP-address allocation for accessing a
home based network, DHCPv4-functions, DHCPv6-functions, providing
server functionalities, providing relay functionalities, providing
client functionalities and providing downlink local packets in a
tunnel, especially providing an inclusion of downlink local packets
in a GTP tunnel at an S1-U interface. It may also be possible to
provide routing of uplink UE IP packets according to UE IP source
address to a L-SGi or to a PDN-GW. Further examples for a
BOGW-function may be providing local IP address signaling in
control messages and providing local IP address signaling in
control messages (GTP, NAS), meaning providing local IP address
signaling in control messages, such as GTP and NAS and providing
downlink local packets in a tunnel, especially providing an
inclusion of downlink local packets in a GTP tunnel at an S1-U
interface.
[0016] According to an exemplary embodiment of the invention the
network device may be adapted to support a breakout service based
on a received information, which information is for example a UE
Requested PDN Connectivity, a UE Triggered Service Request, a UE
Requested Bearer Resource Modification, a Dedicated Bearer
Activation, a Bearer Modification, a Network Triggered Service
Request, a S1 Release procedure, a UE-initiated Detach procedure
for E-UTRAN, a MME Initiated Dedicated Bearer Deactivation, a UE
Requested PDN disconnection and a Create/Update (Default) Bearer
Request.
[0017] The received information may be a trigger signal for
initiating a breakout or an off-load of packets, i.e. IP packets
within the network.
[0018] According to an exemplary embodiment of the invention the
network device may be adapted to provide a local IP address. It may
be foreseen that the local IP address may be provided within NAS
signaling. It may also be possible that the local IP address may be
provided in-band with IP methods, such as DHCP, IPv6, etc., by for
example overwriting the IP address in a dual IPv4/IPv6 bearer.
[0019] According to an exemplary embodiment of the invention there
may be provided a method for providing communications traffic
breakout. The method may comprise receiving a trigger signal for
preparing a breakout of a plurality of packets, wherein the
plurality of packets may comprise at least one packet from a first
source and one packet from a second source, evaluating the trigger
signal. In addition, the method may comprise evaluating packets
from a first source and from a second source and distinguishing
packets from the first source from packets from the second
source.
[0020] According to an exemplary embodiment the method may further
comprise analyzing the packets received via a bearer service,
forwarding packets from the first source to the server via the
bearer service, and breaking out, from a bearer service, packets
from the second source and routing the packets from the second
source to a separate network.
[0021] Another example embodiment is an example computer-readable
storage medium having executable computer-readable program code
instructions stored therein. The computer-readable program code
instructions of the example computer-readable storage medium are
for causing a network device to perform various
functionalities.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Embodiments of the present invention are described below
with reference to the accompanying drawings, which are not
necessarily drawn to scale, wherein:
[0023] FIG. 1 illustrates a system for communications traffic
breakout according to an example embodiment of the present
invention;
[0024] FIG. 2 illustrates a reference architecture to support LIPA
and SIPTO in E-UTRAN according to an example embodiment of the
present invention;
[0025] FIG. 3 illustrates a LIPA/SIPTO Bearer Setup procedure using
UE Service request according to an example embodiment of the
present invention;
[0026] FIG. 4 illustrates a LIPA/SIPTO Bearer Setup procedure using
UE requested bearer resource modification procedure resulting to
dedicated bearer activation according to an example embodiment of
the present invention;
[0027] FIG. 5 illustrates a LIPA/SIPTO Bearer Setup procedure using
UE requested bearer resource modification procedure resulting to
modification of an existing bearer according to an example
embodiment of the present invention;
[0028] FIG. 6 illustrates a LIPA/SIPTO Bearer Setup procedure using
Dedicated Bearer Activation according to an example embodiment of
the present invention;
[0029] FIG. 7 illustrates a first example of a Local UE Paging
Trigger from (H)eNB to MME in LIPA/SIPTO according to an example
embodiment of the present invention;
[0030] FIG. 8 illustrates a second example of a Local UE Paging
Trigger controlled by (H)eNB/L-GW in LIPA/SIPTO according to an
example embodiment of the present invention;
[0031] FIG. 9 illustrates a network architecture with SIPTO at a
S-GW and a single PDN connection according to an example embodiment
of the present invention; and
[0032] FIG. 10 illustrates a network apparatus according to an
exemplary embodiment of the present invention.
DETAILED DESCRIPTION
[0033] Example embodiments of the present invention will now be
described more fully hereinafter with reference to the accompanying
drawings, in which some, but not all embodiments of the invention
are shown. Indeed, the invention may be embodied in many different
forms and should not be construed as limited to the embodiments set
forth herein; rather, these embodiments are provided so that this
disclosure will satisfy applicable legal requirements. Like
reference numerals refer to like elements throughout. The terms
"data," "content," "information," and similar terms may be used
interchangeably, according to some example embodiments of the
present invention, to refer to data capable of being transmitted,
received, operated on, and/or stored.
[0034] The illustration of the drawings is schematic. In different
drawings, similar or identical elements are provided with the same
reference numerals.
[0035] Various example embodiments of the present invention support
communications traffic breakout from a bearer service. According to
various example embodiments, a bearer service may be a type of
virtual point-to-point connection or transport service between two
network entities or end points. For example, the bearer service may
be a packet data protocol (PDP) context and/or a enhanced packet
system (EPS) bearer. As such, the bearer service may support
long-term evolution (LTE) based communications techniques. The end
points of the bearer service may be a client device, such as, for
example, user equipment (UE) in the form of a mobile terminal, and
a server, such as, for example, a packet data network gateway
(PDN-GW) and/or a general packet radio service (GPRS) gateway
support node (GGSN). In some example embodiments, a bearer service
is a transport service with specific and defined quality of service
(QoS) attributes.
[0036] According to various example embodiments of the present
invention, a client device may maintain a bearer service to a
server that provides access to a core network of a wireless
communications system. Having established the bearer service with
the server, the client device may also wish to communicate, perhaps
more locally, with a second, separate network, such as a local area
network (LAN). To conduct communications with the second network,
the client device may be configured to transmit packets intended
for the second network through the bearer service to an
intermediate middlebox, wherein the middlebox may be a breakout
gateway (BOGW) or a local breakout gateway (L-GW).
[0037] The middlebox may be configured to forward packets intended
for the core network to the server, and breakout and route packets
intended to the second network to the second network. Since the
packets intended for the second network may be intercepted by the
middlebox, the server and the core network may be unaware of the
packets intended for the second network. In this manner,
simultaneous support for both core network communications and local
area network communications may be achieved through multiple
interfaces via a single bearer service. Example embodiments
therefore support local IP access (LIPA), without visibility, or
with limited visibility, to the core network.
[0038] To provide for breaking packets intended for the second
network out of the bearer service, the client device may establish
separate sources for the packets intended for the server, and the
packets intended for the second network, respectively. In other
words, a first source may be established for communications to the
server and the core network, and a second source may be established
for communications to the second network. In some example
embodiments, the sources may be treated as separate communications
interfaces within the client device. In this regard, applications
executed on the client device may interact with the sources as
physical interfaces, and behave accordingly, such as by performing
source address selection.
[0039] The packets from each of the separate sources may acquire
particular characteristics based on the type of source. A source
may be defined, for example, by a distinct source address (e.g.,
source internet protocol (IP) address) and/or by a communications
protocol that is used to generate packets from the particular
source (e.g., point-to-point protocol (PPP), internet protocol,
Ethernet, or the like). Although the client device may employ more
than one source, the packets generated for each of the sources may
be transmitted together via the bearer service. In this regard,
according to some example embodiments, the packets from each of the
sources may be multiplexed and transmitted using a common radio to
the bearer service.
[0040] In light of the foregoing, FIG. 1 illustrates an example
system for communications traffic breakout according to various
example embodiments of the present invention. The system of FIG. 1
shows a client 100, a middlebox 102, a server 104, a network 106,
and a network 108. The client 100 may be any type of wired or
wireless communications device such as a mobile terminal, a laptop
computer with a wireless modem, or other type of user equipment.
The middlebox 102 may be a network communications entity, such as a
base station configured as an enhanced node B (eNB) or a Home eNB
(HeNB).
[0041] The middlebox 102 may provide connections to a server 104
and a network 108. The network 108 may be, for example, local to
the middlebox 102 and/or the client 100, and the network 108 may be
a wired or wireless LAN, which may be multicast enabled. The server
104 may be another network communications entity, such as a PDN-GW
and/or a GGSN. The server 104 may provide a connection to a network
106, which may be the core network.
[0042] A bearer service 110 may also be established between the
client 100 and the server 104. According to some example
embodiments, the bearer service 110 may support a point-to-point
connection, and be configured as, for example, a PDP context and/or
an EPS bearer. The bearer service 102 may pass through the
middlebox 102, and the middlebox 102 may be configured to
facilitate maintaining the bearer service 102 between the client
100 and the server 104.
[0043] In general, the client 100 may be configured to establish at
least two sources (e.g., first source 112 and second source 114)
for providing communications traffic via the bearer service 110.
Data packets from each of the first source 112 and the second
source 114 may be generated having characteristics based on the
type of source. According to some example embodiments, the data
packets from the sources may be multiplexed by the multiplexer 116
and provided to the bearer service 110 as combined traffic 118. The
combined traffic 118 from the client 100 may be received or
intercepted by the middlebox 102, and the middlebox 102 may be
configured to analyze the packets to determine whether the packets
originated from the first source 112 or the second source 114.
Packets from the first source may be passed or forwarded to the
server 104 as first source traffic 120. Packets from the second
source may be broken out of the bearer service 110 and routed as
second source breakout traffic 122 to the network 108.
[0044] While the example embodiments described herein address
situations involving one source (e.g., the second source 114) to
support packet breakout from the bearer service, any number of
sources may be configured for packet breakout. In this regard, a
client device (e.g., during random access signaling or via some
other means such as dynamic host configuration protocol signaling)
may establish, or be requested to establish, a number of sources
and associated interfaces. In this regard, a point-to-point
connection via the bearer service 110 to the "Internet" or
"Operator intranet" may be established, and sources configured for
packet breakout may be configured for the same or different
destinations, such as the "Internet", "Corporate Intranet" or "Home
network."
[0045] According to various example embodiments, packets for the
first and second source may be generated in a number of ways.
According to some example embodiments, as further described below,
a first IP address associated with a first source 112 may be
established for the client 100 for use with a point-to-point
connection supported by the bearer service 110, and a second, and
possibly local, IP address associated with the second source 114
may be established. The second IP address may also be used with the
bearer service 110, and the second IP address may be known to the
middlebox 102. As such, the middlebox 102 may breakout and route
packets having the second IP address to, for example a local
network (e.g., network 108).
[0046] According to some example embodiments, the second IP address
may be determined and utilized in a manner that may not be detected
by the server 104, due to the middlebox 102 intercepting and
routing the traffic associated with the second IP address to the
network 108. To establish the second IP address, client 100 may be
notified by the middlebox 102 about possibility for configuration
of a second IP address for the bearer service 110. The client 100
may communicate with the middlebox 102 and configure the second IP
address and a point-to-point connection. In some example
embodiments, the client 100 may select the address unilaterally,
while in other embodiments the middlebox 102 may be employed to
assist in the selection of a second address. The middlebox 102 may
thereafter be configured to inspect the traffic of the bearer
service 110, and make forwarding and routing decisions based on
addresses (e.g., the source and/or destination addresses) of the
packets transmitted from the client 100.
[0047] In accordance with another example embodiment, the client
100 may be configured to generate different protocol type packets
for the respective sources. For example, packets for the first
source may be formatted in accordance with a first protocol (e.g.,
IP) and packets for the second source may be formatted in
accordance with a second protocol (e.g., Ethernet). Alternatively,
in some example embodiments, packets for the second source 114 may
be generated in a first protocol, and subsequently encapsulated in
a second protocol (e.g., Ethernet over IP). Regardless of the
specific characteristics of the packets, the middlebox 102 may be
configured to distinguish packets for the first source 112 from
packets for the second source 114, and route the packets
accordingly (e.g., breakout packets form the second source
114).
[0048] With respect to routing the communications traffic of the
bearer service 110, the middlebox 102 may be configured to pass
traffic from the first source 112 in the direction of the server
104 and the network 106 (e.g., the core network) as first source
traffic 120. However, the middlebox 102 may also be configured to
analyze characteristics of the packets (e.g., the source addresses
of the packets, the protocols of the packets, whether an
encapsulation of protocols is present, or the like) transmitted
from the client 100, and breakout packets from the bearer service
110 based on the analysis. The packets that are broken out of the
bearer service 110 may be directed to other destinations, such as
network 108, which may be a home network or the Internet.
[0049] The following provides additional details of various example
embodiments of the present invention. In particular, example
embodiments are described for implementing the general concept into
a communication network, especially into a communication network
providing LIPA services and SIPTO services, for example providing
these services according to the 3GPP standardization
environment.
[0050] In communication networks a mobile device may use more than
one service simultaneously. For example a mobile phone may provide
a telephone call and may have internet access at the same time. In
communication networks using 3GGP technology a so called Local IP
Access (LIPA) may be provided which may allow an IP-capable
(IP=internet protocol) UE (UE=user equipment), such as a mobile
phone, to be connected via a eNB or a HeNB (eNB=e Node B;
HeNB=HNB=Home e-Node B; (H)eNB =(Home)eNodeB) over a direct access
to other IP-capable devices in a local residential/corporate IP
network.
[0051] A SIPTO service may be understood as a Selected IP Traffic
Offload. With a local interface an offload network may be available
due to a SIPTO functionality in a local gateway (L-GW). With the
same local interface or another local interface a LAN may be
available due to a LIPA functionality the local gateway. In the
following if not otherwise explained, there may be no
differentiation between the LIPA functionality and the SIPTO
functionality. Therefore in the following the term "LIPA/SIPTO" may
be utilized. Both functionalities may be utilized in order to
provide a breakout via a BOGW into a second network, for example an
offload network or a LAN.
[0052] It may be assumed that the LIPA/SIPTO services may be
provided by using Local IP addresses assigned from the L-GW that
may be visible to the client 100 or a UE i.e. the local IP
addresses may be configured in an UE IP Stack and may be used for
LIPA/SIPTO Bearer Services so that the use of a NAT function may be
not necessary.
[0053] It should be noted that the use of a Local IP Address in the
UE may be different when LIPA/SIPTO service may be supported by
using Multiple PDN connectivity. With other words, there may be
provided a utilization of separate IP addresses in the UE per each
PDN connection. Thus, the LIPA/SIPO service may be managed by using
a Multiple PDN Connectivity.
[0054] It may be possible that the LIPA/SIPTO service may be
visible to the UE also in the "Single APN" based LIPA/SIPTO case.
With other words, the UE and the network may support a required
session management scenarios and may use Local IP Addresses in
order to manage the related EPS Bearer Services for LIPA/SIPTO.
[0055] According to an exemplary embodiment of the invention there
may be provided solutions for "Single APN" based LIPA/SIPTO Session
Management procedures in the LTE/SAE networks. These procedures may
have a minimal impact on the Evolved Packet Core (EPC) nodes i.e.
the MME and the S-GW or P-GW.
[0056] The local breakout point may be assumed to be taken from a
co-located L-GW in the (H)eNB supporting LIPA/SIPTO services
providing connectivity to Local IP Networks that may, or may not be
part of the MNO network.
[0057] FIG. 2 shows a LIPA/SIPTO architectural according to an
exemplary embodiment of the present invention for the case of
E-UTRAN and an eNB, for example a macro eNB. Analogous
architectural embodiments may apply for networks comprising a HeNB.
Moreover, analogous architectural embodiments may apply for
networks comprising a UTRAN, comprising local breakout at least at
RNC or at least at HNB level. In the UTRAN case, the GGSN may map
onto PDN GW, and SGSN may map onto S-GW and onto MME, wherein the
mapping onto S-GW may be a user plane part and the mapping onto MME
may be a control plane part.
[0058] FIG. 2 shows several network devices 100, 101, 102, 103,
105, 107, 109, 113, which may be interconnected to each other via
interfaces, i.e. interfaces LTE-Uu, L-SGi, S1-MME, S1-U, S11,
L-Ext, S5, Gx, Rx and SGi. An UE 100 which may communicate via a
eNB 101 or a HeNB 101 with an first network 106, which is a IP
network. The (H)eNB may be connected with a S-GW 107. The S-GW 107
may be connected via a S5 interface with a P-GW 109. the S-GW 107
and the P-GW 109 may be co-located or combined within one network
device 500, a so called S-/P-GW 111. A L-GW 102 may be co-located
to the (H)eNB 101.
[0059] According to an exemplary embodiment of the present
invention the Local Gateway (L-GW) 102 may co-located with the
(H)eNB 101 within one network device (H)eNB/L-GW 103. The L-GW 102
may provide several functions for LIPA/SIPTO support. One of these
functions may be a Gateway bridging and or routing LIPA/SIPTO
Bearer over radio to/from a Local IP Network, e.g. the internet, an
enterprise network or home network via a L-SGi. Moreover, the L-GW
102 may provide an ECM-IDLE mode downlink packet buffering and an
initiation of a network triggered service request procedure.
Furthermore, the L-GW 102 may perform collecting UL traffic
statistics and DL traffic statistics. In addition the L-GW 102 may
assist in UE IP address allocation to access a home based IP
network. The L-GW 102 may also provide DHCPv4 functions (server,
relay and client) and also DHCPv6 (server, relay and client)
functions.
[0060] When the LIPA/SIPTO traffic breaks out to Local IP Networks
directly from (H)eNBs it may be assumed that the L-GW function may
be a part of the EUTRAN. Thus, the LIPA/SIPTO reference
architecture may apply a S1-MME interface for the L-GW (Local
Gateway) 102 control signalling in order to keep an existing
EUTRAN-EPC split over the S1-Interface untouched. An optional
"L-Ext" tunnel 115 may be configured for Managed Remote Connection
between the P-GW 109 and a Residential Gateway in the Local IP
Network.
[0061] Functional assumptions for the LIPA/SIPTO session management
may be the following: A LIPA/SIPTO Session Management may be
handled at NAS Level either by using Multiple PDN-Support, or
within Single PDN Connection by using a modified or a dedicated
Bearer Request procedure. From the UE Point of view Local U-Plane
handling may be transparent and LIPA/SIPTO Sessions may be mapped
either to an UE Requested PDN Connectivity (APN may be associated
to local "L-GW"), to a dedicated EPS Bearer (within single APN), or
to a modified EPS Bearer (within single APN). Moreover, the MME may
comprise an APN handling procedure for an UE Requested PDN
connection for LIPA/SIPTO service, or for a dedicated bearer
request in the single APN case. There may be UEs which may not
provide LIPA/SIPTO capability then a subscription may be supported
with an operator controlled SIPTO feature transparently to the UE
within single APN. It may be assumed that the UE transparent SIPTO
traffic offload or SIPO traffic breakout may happen from the
Operator Site and LIPA providing Intranet Type access may require
user being aware of service activation. Moreover, the UE may be
anchored to the MME on the C-plane. It may be provided that the
"Default EPS Bearer" Service may be "Always On" from the S-/P-GW of
the EPC. Furthermore, a CSG (Closed Subscriber Group) mechanisms
may be used for Mobility Management. In addition, it may be
foreseen that a (H)eNB with LIPA/SIPTO may provide a "L-GW"
function. In addition, a minimal set of S-GW and P-GW functions may
be utilized in (H)eNB for handling "Native IP". A "Native IP" may
be a normal IP networking used in IT-technology in contrast to a
proprietary 3GPP specified way. The "L-GW" function may be
controlled over the S1-MME Interface. Thus, the Core Network
Interfaces like S11 may be omitted in (H)eNB by delivering the
required LIPA/SIPTO control information in the S1AP (S1 Application
protocol) "E-RAB Management Messages". It may be foreseen that the
LIPA/SIPTO Service may work based on temporary E-UTRAN identifiers
without necessitating storing the user sensitive context data like
IMSI locally in the (H)eNB/L-GW.
[0062] The following procedures may be applicable for supporting
LIPA/SIPTO services: UE Requested PDN Connectivity (Multiple APN
based LIPA/SIPTO solution), UE Triggered Service Request, UE
Requested Bearer Resource Modification, Dedicated Bearer
Activation, Bearer Modification, Network Triggered Service Request
(how paging trigger for UE using LIPA/SIPTO can be indicated to the
MME), S1 Release procedure, UE-initiated Detach procedure for
E-UTRAN, MME Initiated Dedicated Bearer Deactivation and UE
Requested PDN disconnection.
[0063] An UE Requested PDN Connectivity procedure may apply for the
Multiple PDN Connectivity or Multiple APN based LIPA/SIPTO
service.
[0064] In the following more details in relation to LIPA/SIPTO
service management functions or LIPA/SIPTO procedures and methods
relating to LIPA/SIPTO may be described, i.e. in relation to a UE
Triggered Service Request, UE Requested Bearer Resource
Modification, Dedicated Bearer Activation, Bearer Modification,
Network Triggered Service Request and S1 Release procedures.
[0065] FIG. 3, FIG. 4, FIG. 5, FIG. 6, FIG. 7 and FIG. 8 illustrate
examples of message diagrams, respectively, in order show exemplary
embodiments for method for providing communications traffic
breakout. In these Figures several steps may be indicated by step
numbers either in a box or at an arrow. These steps may be
performed timely after each other. Moreover, the arrows may
indicate a direction of information flow from one network device to
another network device. Boxes in these figures may indicate actions
taken by a respective network device or decisions to be performed
by a respective network device. The text positioned at the
respective arrow may indicate a message comprising parameters
indicated in brackets.
[0066] FIG. 3 shows a LIPA/SIPTO Bearer Setup procedure using an UE
Triggered Service Request according to an exemplary embodiment. The
UE Triggered Service Request message, shown in step 3 of FIG. 3,
may be executed when the UE 100 may change its status from ECM-IDLE
to ECM-ACTIVE state. This procedure may be utilized in order to
support either UE requested LIPA/SIPTO Bearer setups or Network
Controlled LIPA/SIPTO Bearer setups. In both cases the MME 105 may
be assumed to make a decision whether a LIPA/SIPTO Bearer should be
added in the UE Context data e.g. based on a movement of the UE to
a cell/location where LIPA/SIPTO service is allowed.
[0067] The LIPA/SIPTO bearer service to be setup may be either a
dedicated bearer or a modified bearer linked to a current PDN
connection, which may be especially a single APN, when anew local
IP address has to be configured in the UE 100 in addition to
configuring the (H)eNB/L-GW accordingly.
[0068] A handling of the LIPA/SIPTO bearer service setup upon the
UE Triggered Service Request procedure may be the following: The
MME 105 may be assumed to be aware of UE membership to a CSG and
LIPA/SIPTO may be allowed to the UE. For LIPA/SIPTO bearer handling
the MME 105 may comprise one or more profiles (reflecting
(different) operator policies and or subscriber types and or (H)eNB
backhaul capability) with default values on behalf of the "virtual
P-GW" for LIPA/SIPTO services. Moreover, the (H)eNB/L-GW may be
configured for LIPA/SIPTO support and may be capable to assist the
UE in local IP address allocation and may perform bridging between
LIPA/SIPTO Bearer and "native IP" in the local IP network. A MME
Initiated Dedicated Bearer Activation for LIPA/SIPTO Service may be
triggered by reception of the NAS: "Service Request" message when
the UE has entered to a (H)eNB/Cell supporting LIPA/SIPTO (see step
4 in FIG. 3). This message may be utilized for establishing NAS
signaling connection and of the radio bearers and S1 bearers. This
message may contain S-TMSI and security information for identifying
the client or user. In addition, the "Service Request" message may
comprise an indication for the UE requesting LIPA/SIPTO bearer
service. This indication may be omitted in the case the LIPA/SIPTO
bearer activation may be always fully network controlled. In order
to trigger Local IP Address configuration in the UE the NAS-PDU in
the bearer setup request message, see step 5 in FIG. 3, may
comprise an indication e.g. in the protocol options. In order to
trigger Local IP Address configuration in the UE the NAS-PDU in the
bearer setup request message (see step 5 in FIG. 3) may comprise an
indication e.g. in the protocol options. In order to activate
LIPA/SIPTO Service in the (H)eNB, the E-RAB parameters may indicate
that S1-u is omitted e.g. by issuing null TEID value.
[0069] FIG. 4 and FIG. 5 show a LIPA/SIPTO Bearer Setup procedure
using UE Requested Bearer Resource Modification according to an
exemplary embodiment. The UE Requested Bearer Resource Modification
procedure may allow the UE 100 to request for a modification of
bearer resources (allocate or release resources) when the UE 100
already has a PDN connection with the S-/P-GW 107, 109 meaning the
default EPS Bearer is activated (see step 1 in FIG. 4 and step 1 in
FIG. 5). This UE requested Bearer Setup procedure may support
LIPA/SIPTO service setups within a single APN by invoking either a
dedicated bearer activation or a bearer modification procedure if
accepted by the network. The MME 105 may perform an access control
for the UE 100 moving to a cell supporting LIPA/SIPTO e.g. based on
the CSG membership verification and possible LIPA/SIPTO
subscription verification. In the LIPA/SIPTO service setup the UE
100 may request a traffic flow aggregate with a reduced QoS in
order to release resources in the PDN GW 109 as the LIPA/SIPTO
traffic does no more pass it, and most of the UE generated traffic
may be off-loaded.
[0070] Handling of the LIPA/SIPTO bearer service setup upon the UE
Requested Bearer Resource Modification procedure may comprise the
following aspects:
[0071] The UE 100 may be aware of LIPA/SIPTO service e.g. in its
CSG cell/network according. Moreover, the MME 105 may be assumed to
be aware of UE membership to a CSG and LIPA/SIPTO may be allowed to
the UE 100 in order to perform the required access control and
reject service request when required. In addition, the LIPA/SIPTO
bearer management may be transparent to the MME 105 by re-using the
existing procedures. The LIPA/SIPTO bearer management may be
transparent to the S-GW 107 and P-GW 109 by re-using the existing
procedures. (H)eNB/L-GW 101, 102 may be assumed to be configured
for LIPA/SIPTO support and may be capable to assist the UE 100 in
local IP address allocation and perform bridging between LIPA/SIPTO
bearer and "native IP" in the local IP network. It may be foreseen
that the UE Requested Bearer Resource Modification procedure for
LIPA/SIPTO Service may be triggered by the UE movement to a cell
where LIPA/SIPTO service may be enabled e.g. to a CSG cell, or by
using some indication from Network. The initiation of the procedure
may be automated, or could be done manually by the client or user.
It may be foreseen that the UE 100 may be capable to store a
pre-provisioned QoS profile for a LIPA/SIPTO service.
[0072] In addition the UE 100 may be capable to auto-configure
local IP address with an assistance of the (H)eNB/L-GW 101, 102 for
LIPA/SIPTO bearer service. The UE 100 may be capable to store its
IP address assigned from the P-GW 109 and on demand re-configure,
or use this IP address for non-LIPA/SIPTO services.
[0073] The UE 100 may create and send a NAS: "Request Bearer
Resource Modification" message with a specific TAD (Traffic
Aggregate Description) for LIPA/SIPTO service and may be delivered
via the MME 105 to the S-/P-GW 107, 109. The requested operation in
the TAD may be to add, or modify packet filters and the Protocol
Configuration Options with address auto-configuration by the
UE.
[0074] FIG. 4 illustrates the procedure where the UE 100 is
requesting a dedicated bearer establishment (requested operation in
the TAD is "add"). The P-GW 109 may verify if the UE request can be
accepted and may decide whether a new dedicated bearer service
should be added. Then the P-GW 109 may configure an UE specific
P-GW Context and may respond to the MME 105 via the S-GW 107
accordingly with the S11: "Create Dedicated Bearer Request"
message.
[0075] The MME 105 may create an S1AP: "E-RAB Setup Request"
message with the E-RAB to be modified list and may send it to the
(H)eNB/L-GW 101, 102. The (H)eNB may receive the radio bearer and
S1-u tunnelling parameters in the S1AP: "E-RAB Setup Request"
message. In order to support LIPA/SIPTO services the (H)eNB 101 may
perform an additional check whether the UE 100 is allowed to use
LIPA/SIPTO. Moreover, the (H)eNB 101 may configure LIPA/SIPTO
policies in the eNB UE context and may prepare to assist UE 100 in
its Local IP Address allocation. When a new dedicated bearer
service may be configured, a UE 100 willing to use LIPA/SIPTO
service may initiate an address auto-configuration procedure (DHCP
or IPv6 AAC) that the (H)eNB 100 is monitoring automatically and
when completed (H)eNB 100 may ignore the EPC given S1-u tunnelling
parameters and may start local bridging function in L-GW 102 for
the newly configured local IP address. From now on the UE may use
its local IP Address for LIPA/SIPTO services and the (H)eNB may
detect related traffic in uplink based on the Source Address in IP
lookup.
[0076] It may be possible that these functions for establishing
LIPA/SIPTO Service at EUTRAN-level could be autonomous in the UEs
100 and (H)eNBs 101 configured for LIPA/SIPTO support when no
special requirements will be set to the EPC. However, the EPC may
be aware of LIPA/SIPTO when some IE combination from the UE may be
used to indicate LIPA/SIPTO Bearer Request when P-GW 109, or the
MME 105 may return known parameters to the (H)eNB 101 in order to
omit S1-u e.g. null TEID value.
[0077] FIG. 5 illustrates a procedure with UE requesting
modification of an existing bearer according to an exemplary
embodiment. In the UE requested bearer modification targeting to
LIPA/SIPTO service establishment, it may be possible to degrade QoS
and to release resources in the P-GW 109 as traffic will be
off-loaded. The P-GW 109 may verify if the UE request can be
accepted and may decide whether a bearer service can be modified
according to the UE given TAD (Traffic Aggregate Description). Then
the P-GW 109 may configure the UE specific P-GW Context and may
respond to the MME 105 via the S-GW 107 accordingly with the S11:
"Update Bearer Request message" (see step 5 in FIG. 5). The MME 105
may create a S1AP: "E-RAB Modify Request" message with the E-RAB to
be modified list and may send it to the (H)eNB/L-GW 101,102 (see
step 6 in FIG. 5).
[0078] The (H)eNB 101 may receive new radio bearer parameters in
the S1AP: "E-RAB Modify Request" message as the old S1 tunnelling
parameters are assumed to remain the same. In order to support
LIPA/SIPTO services the (H)eNB 101 may perform an additional check
whether the UE 100 is allowed to use LIPA/SIPTO, may configure
LIPA/SIPTO policies in the eNB UE context and may prepare to assist
the UE 100 in its Local IP Address allocation. As the UE 100 may
have requested degraded QoS in order to release resources in the
EPC and used bearer modification as an indication to the
(H)eNB/L-GW 101,102 to prepare for LIPA/SIPTO service, the (H)eNB
101 may over-ride the EPC given E-RAB parameters and instead apply
the pre-configured QoS parameters in the LIPA/SIPTO policies.
[0079] When a bearer service is modified, a UE 100 willing to use
LIPA/SIPTO service may initiate address auto-configuration
procedure (DHCP or IPv6 AAC) that the (H)eNB 101 is monitoring
automatically and when completed may ignore the old EPC given S1-u
tunnelling parameters and may start local bridging function in the
L-GW 102 for the newly configured local IP address.
[0080] These functions for establishing LIPA/SIPTO Service at
EUTRAN-level could be autonomous in the UEs and (H)eNBs configured
for LIPA/SIPTO support when no special requirements will be set to
the EPC. However, the EPC may be aware of LIPA/SIPTO when some
indication could be delivered to the (H)eNB 101 during the UE
requested bearer resource modification procedure. As the S1
tunnelling parameters may be not delivered in the E-RAB
modification request message then some other indication should be
specified and added there, or use e.g. a preceding SiAP: "UE
Context Modification Request" message for preparing the (H)eNB for
LIPA/SIPTO support (see step 2 in FIG. 6).
[0081] According to further exemplary embodiment of the present
invention a LIPA/SIPTO Bearer Setup Procedure using Dedicated
Bearer Activation may be utilized. A Bearer Activation procedure
may allow the network initiated dedicated bearer service
establishment when the UE already may have a PDN connection with
the PDN GW (Default EPS Bearer may be activated). This procedure
may be utilized to support the Dedicated LIPA/SIPTO Bearer setups
within a single APN.
[0082] As the P-GW 109 in the EPC, or PCRF 113 may be not involved
with the LIPA/SIPTO service the MME 105 may be assumed to make a
decision whether LIPA/SIPTO Bearer should be added in the UE
Context data e.g. based on UE movement to a cell/location where
LIPA/SIPTO service is allowed.
[0083] Handling of the LIPA/SIPTO dedicated bearer activation
procedure in control of the MME 105 may be the following: The MME
105 may be assumed to be aware of UE membership to a CSG and
LIPA/SIPTO may be allowed to the UE 100. For LIPA/SIPTO bearer
handling the MME 105 may include one or more profiles (reflecting
(different) operator policies and or subscriber types and or (H)eNB
backhaul capability) with default values on behalf of a "virtual
P-GW server" for LIPA/SIPTO services. This information could be
stored in a "virtual P-GW Server" for LIPA/SIPTO located in the
P-GW 109 when ordinary S11 procedures can be executed. The
(H)eNB/L-GW 101,102 may be assumed to be configured for LIPA/SIPTO
support and may be capable to assist the UE 100 in local IP address
allocation and may perform bridging between LIPA/SIPTO Bearer and
"native IP" in the local IP network 108. A MME Initiated Dedicated
Bearer Activation for LIPA/SIPTO Service may be triggered when the
UE 100 may have entered to a (H)eNB/Cell 101 supporting LIPA/SIPTO.
The MME 105 may update the eNB UE Context Data with the required
LIPA/SIPTO Information prior to the actual dedicated bearer setup,
see the steps 2 and 3 in FIG. 6. In order to trigger Local IP
Address configuration in the UE 100 the NAS-PDU in the bearer setup
request message may contain some indication e.g. in the protocol
options. In order to activate LIPA/SIPTO Service in the (H)eNB 101,
the E-RAB parameters may indicate that S1-u is omitted e.g. by
issuing null TEID value. The MME 105 may be provided with
intelligence to activate itself for providing an EPS Bearer
Services.
[0084] According to another embodiment of the present invention a
LIPA/SIPTO Bearer Setup Procedure using Bearer Modification may be
utilized. The Bearer Modification procedure may allow the network
initiated bearer service modifications when the UE 100 may already
have a PDN connection with the PDN GW (Default EPS Bearer is
activated). This procedure may be utilized in order to support the
LIPA/SIPTO Bearer setups within a single APN.
[0085] Therefore, the MME 105 may be assumed to make a decision
whether LIPA/SIPTO Bearer should be modified from one already
existing EPS bearer in the UE Context data e.g. based on UE
movement to a cell/location where LIPA/SIPTO service is allowed.
The rest of the Bearer Modification procedure may be the same as
illustrated in FIG. 5 except the MME 105 may initiate the network
controlled procedure.
[0086] According to a further exemplary embodiment of the present
invention a Network Triggered Service Request (Local Paging
Trigger) may be utilized. Another function of the S11 interface may
be to deliver the trigger for idle to active state change in case
UE related downlink data may arrive in the S-GW 107. In case of
LIPA/SIPTO from (H)eNB/L-GW 101, 102 the local downlink traffic may
not pass the S-GW 107 or P-GW 109 located in the EPS, so some
further mechanism may be needed to be specified for local paging
trigger.
[0087] The assumption in Local IP Access is that the user plane for
the LIPA/SIPTO service may terminate in the latest serving
HeNB/L-GW 101,102 that may become kind of a local paging agent
while the UE 100 may be moved to its Idle-state. It may be foreseen
that the active to Idle transition the UE specific Radio Resources
in the HeNB 101 may be released, UE "RAN context" data may be moved
to MME 105 and S1 related resources may be released as usual. The
L-GW functions and the related UE context data may be retained in
the HeNB/L-GW 101, 102 including some paging token to identify the
UE 100 e.g. S-TMSI.
[0088] Upon reception of UE related DL data for LIPA there may be
needed a further Paging triggering message from the (H)eNB/L-GW
101, 102 to the MME 105 over the S1-MME interface after which the
MME 105 may continue the UE paging procedure. As the UE-associated
S1 signalling connection may be removed after the S1 Release
procedure, the local paging trigger may be transferred using non-UE
associated signalling. This functionality for the S1-MME interface
may be combined e.g. with the S1AP: "eNB Direct Information
Transfer" message like shown in FIG. 7 in step 1.
[0089] The purpose of the eNB Configuration Transfer procedure may
be to transfer RAN configuration information from the (H)eNB 101 to
the MME 105 in unacknowledged mode. The MME 105 may not interpret
the transferred RAN configuration information. However, the S1AP:
"eNB Direct Information Transfer" message or a further message may
be utilized so that the message (step 1 in FIG. 7) may deliver the
Local UE Paging Trigger information from the (H)eNB/L-GW 101, 102
to the MME 105 in LIPA/SIPTO services. The required information
elements to identify the UE 100 and to indicate paging may be
S-TMSI and cause "Downlink Data Notification".
[0090] Another alternative may be to perform paging locally in the
LIPA/SIPTO service area in control of the latest serving
(H)eNB/L-GW 103. This may be possible in case the current S-TMSI
for the UE may be available in the (H)eNB/L-GW 103. FIG. 8
illustrates the local paging procedure in EUTRAN. For local UE
paging it may used a S-TMSI as an UE Identifier. A local paging may
be performed transparently to the EPC.
[0091] According to another exemplary embodiment of the present
invention a S1 Release Procedure with LIPA/SIPTO Services may be
utilized. A S1 Release procedure may be used to release the logical
S1-MME signaling connection and all radio and S1 bearers for a UE
100. It also moves the UE from ECM-CONNECTED to ECM-IDLE both in
the UE 100 and MME 105, and normally all the UE related context is
deleted in the (H)eNB.
[0092] In LIPA/SIPTO Services the user plane terminates in the
latest serving (H)eNB/L-GW 101,102 that may be kind of a UE proxy
towards the local IP network. In order to support local paging the
L-GW functions and the related UE context data may be retained in
the (H)eNB/L-GW 101,102 even the S1 Release Procedure may delete
all UE context.
[0093] The remaining L-GW function may be a "paging agent" that may
wait for a UE related downlink data and upon reception of such
initiates the Network Triggered Service Request procedure like the
S-GW 107 may perform usually in the EPC.
[0094] When the UE specific S1 connection may be released it means
that the link between the eNB UE Context and the MME UE Context may
be lost. Thus, the S1 Release Procedure may be modified so that the
(H)eNB/L-GW may receive some information elements from the MME 105
that may be used to identify the UE 100 to be paged. It may be
possible to store the current S-TMSI in the remaining L-GW context
in the (H)eNB 101 as it may be used as the paging token in the MME
105 and the UE 100 as well.
[0095] Here it should be noted that the local paging agent function
in the (H)eNB/L-GW 101, 102 may have a configurable lifetime after
which all the UE related resources may be deleted.
[0096] According to another exemplary embodiment of the present
invention there is provided a middlebox 102 or a breakout gateway
102 (BOGW) or a local Gateway 102 (L-GW) in a S-GW 107, especially
a S-SAE-GW of the EPC as shown in FIG. 9. Thus, it is proposed to
enhance the S-GW 107 by one or a plurality of functions of a BOGW
102. This BOGW functionality may comprise a related allocation of a
second local IP Address for the UE, especially the allocation of IP
address from local pool, providing DHCP (IP v4, IPv6) and or
routing advertisement for the local link (IPv6). A further
functionality of the BOGW 102 may be an optional enhancement of S11
control signalling with the MME 105, especially a provisioning of a
second IP Address for NAS signalling MME-UE. It may also be
foreseen that the MME 105 may provide control information to the
S-GW 107 if the related PDN connection is subject to SIPTO. An
other exemplary functionality of the BOGW may routing of uplink UE
IP packets according to UE IP source address to local SGi or to
PDN-GW. It may be foreseen that the BOGW may provide an inclusion
of downlink local IP packets in the GTP tunnel at S1 -U interface.
It may also be foreseen a traffic shaping control and or a policy
control to reserve a certain amount of bandwidth for the traffic
flows that traverse the EPC (PDN-GW).
[0097] According to an exemplary embodiment of the invention the
locally acquired IP address may be signaled in a default bearer NAS
signaling/PDP context signaling. For this a field "local offload IP
address" may be utilized. This would be suitable for the UE 100 to
distinguish the addresses.
[0098] In a dual PDP context according to operator policy the S-GW
107 may overwrite the IPv4 or IPv6 address assigned by a P-GW,
especially a PDN-GW 109 with the local address. The applications in
the UE 100 may be also provided with policies and or
pre-configuration, e.g. for IMS to use IPv6 addresses, that may
provide the usage of the operator central PDN-GW 109 with all
operator feature support, all other applications may use IPv4
addresses. This would also fit with the use of always on IPv6
addresses (need a large amount) and dynamically assigned temporary
IPv4 addresses e.g. for Web browsing.
[0099] According to an exemplary embodiment of the invention the
locally acquired IP address may be signaled in-band in the
bearer/tunnel to the UE 100. A DHCP request or all DHCP requests
from the UE 100 may be intercepted by the S-GW 107 and may handled
locally, the default bearer IP Address from the PDN-GW 109, may be
allocated via Session management/NAS signaling. The S-GW 107 may be
injecting router advertisements for IPv6.
[0100] Thus, the S-GW may be located as BOGW using an existing
gateway (GW) selection mechanisms, the subscription of the user
(candidate for LBO) and the capability of the S-GW 107 to provide
offload may taken into account as an additional input parameters
for the S-GW selection procedure.
[0101] The S-GW as BOGW, meaning a combined network device 115, may
serve also as mobility anchor. This may reduce the number of
offload traffic session breaks due to mobility compared to
solutions based on BS integrated SIPTO or a BOGW above BS without
S-GW functionality. Only a subset of GGSN and P-GW functions may be
utilized for implementing SIPTO in the S-GW 107 e.g. to perform
local IP address assignment, DHCP client/server, basic charging
functionality.
[0102] As a result, a legal interception of SIPTO traffic may be
implemented by S-GW functionality as this may be part of the S-GW
functions. Also the standard Paging functionality of the S-GW 107
may be reused for local traffic to allow the UE 100 to be activated
if local downlink data arrive at the local SGi interface and the UE
100 may be in IDLE mode.
[0103] There may be not a requirement of an additional/dedicated
session management and a bearer management signalling at the MME
105, the S-GW 107 and UE 100 as the function may be connected to a
default bearer establishment.
[0104] Pre-defined parameters and or profiles may be user in the
S-GW 107 to control the local SIPTO traffic. This may be e.g. the
amount of bandwidth that the local link can acquire from the
overall bandwidth resource of the PDN connection. One or more
pre-defined Local IP access parameters may be pre-provisioned to a
SIPTO Service function.
[0105] FIG. 10 shows schematically an exemplary embodiment of a
network device 500 comprising a receiving unit 501, a sending unit
502 and an evaluating unit 503. The receiving unit 501 may be
adapted to receive a trigger signal 510 for preparing a breakout or
an off-load of a plurality of packets 520. The plurality of packets
520 comprises at least one packet from a first source 112 and at
least one packet from a second source 114. The evaluating unit 503
may be adapted to evaluate a received trigger signal 510 and to
evaluate packets from the first source 112 and packets from the
second source 114. Moreover, the evaluation unit 503 may be adapted
to distinguish packets from the first source 112 and packets from
the second source 114. The evaluation unit 503 may comprise a
processor 504 and a memory 505 or may be connected with a processor
504 and or a memory 505. Moreover, the network device 500 may
comprise a local interface 506. The local interface 506 may provide
a connection to a second network 108. The sending unit 502 may be
connected with the local interface 506. Moreover, the sending unit
502 may be adapted to send packets to a first network 106 and to a
separate network or second network 108. The second network 108 may
receive packets from a breakout of the plurality of packets 520
received by the network device 500.
[0106] Furthermore, the network devices 500 or network elements 500
and their functions described herein may be implemented by
software, e.g. by a computer program product for a computer, or by
hardware. In any case, for executing their respective functions,
correspondingly used devices, such as an interworking node or
network control element, like an MGCF of an IMS network comprise
several means and components (not shown) which are required for
control, processing and communication/signaling functionality. Such
means may comprise, for example, a processor unit for executing
instructions, programs and for processing data, memory means for
storing instructions, programs and data, for serving as a work area
of the processor and the like (e.g. ROM, RAM, EEPROM, and the
like), input means for inputting data and instructions by software
(e.g. floppy diskette, CD-ROM, EEPROM, and the like), user
interface means for providing monitor and manipulation
possibilities to a user (e.g. a screen, a keyboard and the like),
interface means for establishing links and/or connections under the
control of the processor unit (e.g. wired and wireless interface
means, an antenna, etc.) and the like.
[0107] For the purpose of the present invention as described herein
above, it should be noted that: [0108] an access technology via
which signaling is transferred to and from a network element or
node may be any technology by means of which a node can access an
access network (e.g. via a base station or generally an access
node). Any present or future technology, such as WLAN (Wireless
Local Access Network), WiMAX (Worldwide Interoperability for
Microwave Access), BlueTooth, Infrared, and the like may be used;
although the above technologies are mostly wireless access
technologies, e.g. in different radio spectra, access technology in
the sense of the present invention implies also wirebound
technologies, e.g. IP based access technologies like cable networks
or fixed lines but also circuit switched access technologies;
access technologies may be distinguishable in at least two
categories or access domains such as packet switched and circuit
switched, but the existence of more than two access domains does
not impede the invention being applied thereto, [0109] usable
access networks may be any device, apparatus, unit or means by
which a station, entity or other user equipment may connect to
and/or utilize services offered by the access network; such
services include, among others, data and/or (audio-) visual
communication, data download etc.; [0110] a user equipment may be
any device, apparatus, unit or means by which a system user or
subscriber may experience services from an access network, such as
a mobile phone, personal digital assistant PDA, or computer; [0111]
method steps likely to be implemented as software code portions and
being run using a processor at a network element or terminal (as
examples of devices, apparatuses and/or modules thereof, or as
examples of entities including apparatuses and/or modules
therefore), are software code independent and can be specified
using any known or future developed programming language as long as
the functionality defined by the method steps is preserved; [0112]
generally, any method step is suitable to be implemented as
software or by hardware without changing the idea of the invention
in terms of the functionality implemented; [0113] method steps
and/or devices, apparatuses, units or means likely to be
implemented as hardware components at a terminal or network
element, or any module(s) thereof, are hardware independent and can
be implemented using any known or future developed hardware
technology or any hybrids of these, such as MOS (Metal Oxide
Semiconductor), CMOS (Complementary MOS), BiMOS (Bipolar MOS),
BiCMOS (Bipolar CMOS), ECL (Emitter Coupled Logic), TTL
(Transistor-Transistor Logic), etc., using for example ASIC
(Application Specific IC (Integrated Circuit)) components, FPGA
(Field-programmable Gate Arrays) components, CPLD (Complex
Programmable Logic Device) components or DSP (Digital Signal
Processor) components; in addition, any method steps and/or
devices, units or means likely to be implemented as software
components may for example be based on any security architecture
capable e.g. of authentication, authorization, keying and/or
traffic protection; [0114] devices, apparatuses, units or means can
be implemented as individual devices, apparatuses, units or means,
but this does not exclude that they are implemented in a
distributed fashion throughout the system, as long as the
functionality of the device, apparatus, unit or means is preserved,
[0115] an apparatus may be represented by a semiconductor chip, a
chipset, or a (hardware) module comprising such chip or chipset;
this, however, does not exclude the possibility that a
functionality of an apparatus or module, instead of being hardware
implemented, be implemented as software in a (software) module such
as a computer program or a computer program product comprising
executable software code portions for execution/being run on a
processor; [0116] a device may be regarded as an apparatus or as an
assembly of more than one apparatus, whether functionally in
cooperation with each other or functionally independently of each
other but in a same device housing, for example.
[0117] Many modifications and other embodiments of the inventions
set forth herein will come to mind to one skilled in the art to
which these inventions pertain having the benefit of the teachings
presented in the foregoing descriptions and the associated
drawings. Therefore, it is to be understood that the invention is
not to be limited to the specific embodiments disclosed and that
modifications and other embodiments are intended to be included
within the scope of the appended claims. Moreover, although the
foregoing descriptions and the associated drawings describe example
embodiments in the context of certain example combinations of
elements and/or functions, it should be appreciated that different
combinations of elements and/or functions may be provided by
alternative embodiments without departing from the scope of the
appended claims. In this regard, for example, different
combinations of elements and/or functions other than those
explicitly described above are also contemplated as may be set
forth in some of the appended claims. Although specific terms are
employed herein, they are used in a generic and descriptive sense
only and not for purposes of limitation.
[0118] It should be noted, that reference signs in the claims shall
not be construed as limiting the scope of the claims.
LIST OF ABBREVIATIONS
[0119] 3GPP=Third Generation Partnership Project [0120] APN=Access
Point Name [0121] ARP=Address Resolution Protocol [0122]
BOGW=breakout gateway [0123] CN=Core Network [0124] CSG=Closed
Subscriber Group [0125] DAD=Duplicate Address Detection [0126]
DL=downlink [0127] DHCPv4=DHCPv4=Dynamic Host Configuration
Protocol (version 4) [0128] DHCP(v6)=DHCPv6=Dynamic Host
Configuration Protocol (version 6) [0129] ECM=Error Correction Mode
[0130] eNB=enhanced node B [0131] EPC=Evolved Packet Core [0132]
EPS=Evolved Packet System [0133] E-RAB=Evolved Radio Access Bearer
[0134] E-UTRAN=Evolved UTRAN=Evolved Universal Terrestrial [0135]
Radio Access Network [0136] GPRS=general packet radio service
[0137] GTP=GPRS Tunnelling Protocol [0138] GW=gateway [0139]
GGSN=Gateway GPRS Support Node [0140] HeNB=Home eNodeB [0141]
IMSI=International Mobile Subscriber Identity [0142] IETF=Internet
Engineering Task Force [0143] IP=Internet Protocol [0144]
IP(v6/v4)=Internet Protocol (version 6/version 4) [0145] LAN=area
network [0146] LBO=Local BreakOut [0147] LTE=Long-Term Evolution
[0148] LIPA=Local IP Access [0149] L-GW=Local Breakout Gateway
[0150] L-SGi=Local SGi-interface [0151] L2TPv3=Layer 2 Tunneling
Protocol version 3 [0152] MME=Mobility Management Entity [0153]
MNO=Mobile Network Operator [0154] MTU=Maximum Transmission Unit
[0155] NAT=Network Address Translation [0156] NAS=Non-Access
Stratum [0157] PPP=point-to-point protocol [0158] PDN=Packet Data
Network [0159] PDN GW/P-GW=Packet Data Network Gateway [0160]
PDP=Packet Data Protocol [0161] PGW=Packet Data Gateway [0162]
QoS=Quality of Service [0163] RAN=Radio Access Network [0164]
RAS=Radio Access Signaling [0165] SAE=System Architecture Evolution
[0166] STUN=Simple Traversal of User Datagram Protocol (RFC3489)
[0167] SIPTO=Selected IP Traffic Offload [0168] S-GW=Serving
Gateway [0169] S-TMSI=S-Temporary Mobile Subscriber Identity [0170]
TEID=Transport Endpoint Identifier [0171] UE=User Equipment [0172]
UL=uplink
* * * * *