U.S. patent application number 17/245171 was filed with the patent office on 2021-08-12 for controlling the operation of mobile terminals with respect to multiple radio access technologies.
The applicant listed for this patent is Telefonaktiebolaget LM Ericsson (publ). Invention is credited to Mattias Bergstrom, Gunnar Mildh, Magnus Stattin.
Application Number | 20210250824 17/245171 |
Document ID | / |
Family ID | 1000005553311 |
Filed Date | 2021-08-12 |
United States Patent
Application |
20210250824 |
Kind Code |
A1 |
Bergstrom; Mattias ; et
al. |
August 12, 2021 |
Controlling the Operation of Mobile Terminals with Respect to
Multiple Radio Access Technologies
Abstract
According to an aspect, there is provided a method of operating
a mobile device in a communication network. The method comprises
receiving a list of wireless local area network (WLAN) identifiers
from the communication network (600).
Inventors: |
Bergstrom; Mattias;
(Stockholm, SE) ; Mildh; Gunnar; (Sollentuna,
SE) ; Stattin; Magnus; (Upplands Vasby, SE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Telefonaktiebolaget LM Ericsson (publ) |
Stockholm |
|
SE |
|
|
Family ID: |
1000005553311 |
Appl. No.: |
17/245171 |
Filed: |
April 30, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15035641 |
May 10, 2016 |
11026135 |
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PCT/SE2014/051297 |
Nov 4, 2014 |
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17245171 |
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61902362 |
Nov 11, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 84/12 20130101;
H04W 36/0061 20130101; H04W 48/14 20130101; H04W 36/22 20130101;
H04W 48/16 20130101 |
International
Class: |
H04W 36/00 20060101
H04W036/00; H04W 48/16 20060101 H04W048/16; H04W 36/22 20060101
H04W036/22 |
Claims
1. A method of operating a network node in a communication network,
the method comprising: determining whether a list of WLAN
identifiers stored in a mobile device is valid; and sending a list
of WLAN identifiers to the mobile device in response to determining
that the list of WLAN identifiers stored in the mobile device is
not valid.
2. The method of claim 1, wherein sending the list of WLAN
identifiers further comprises sending an identifier for the list of
WLAN identifiers to the mobile device.
3. The method of claim 2, wherein the identifier for the list of
WLAN identifiers comprises a version number and/or a hash
value.
4. The method of claim 1, wherein each of the WLAN identifiers in
the list is a service set identification (SSID), or a basic SSID
(BSSID), or an extended SSID (ESSID), or a homogenous ESSID
(HESSID), or a HotSpot 2.0 identifier.
5. The method of claim 1, wherein the list of WLAN identifiers is
for use by the mobile device in an access network selection and/or
traffic steering procedure.
6. The method of claim 1, further comprising: receiving an
indication of the capability of the mobile device to receive a list
of WLAN identifiers from the mobile device; and sending the list of
WLAN identifiers in response to the received indication indicating
that the mobile device is capable of receiving a list of WLAN
identifiers.
7. The method of claim 1, wherein determining whether the list of
WLAN identifiers stored in the mobile device is valid comprises
determining whether the list of WLAN identifiers is valid for the
area in which the mobile device is located.
8. The method of claim 1, further comprising: receiving a request
for a list of WLAN identifiers from the mobile device; and sending
the list of WLAN identifiers to the mobile device in response to
the received request.
9. The method of claim 1, further comprising: receiving an
indication from the mobile device that the mobile device does not
have a stored list of WLAN identifiers; and sending the list of
WLAN identifiers to the mobile device in response to the received
indication.
10. The method of claim 1, further comprising: determining whether
the mobile device has a valid list of WLAN identifiers stored
therein following a mobility event or a connectivity event by the
mobile device.
11. The method of claim 10, wherein determining whether the mobile
device has a valid list of WLAN identifiers comprises comparing the
identifier for a valid list of WLAN identifiers to an identifier of
a list of WLAN identifiers previously sent to the mobile
device.
12. The method of claim 10, wherein determining whether the mobile
device has a valid list of WLAN identifiers comprises comparing the
identifier for a valid list of WLAN identifiers to an identifier of
a list of WLAN identifiers received from the mobile device as part
of the mobility event or connectivity event signaling.
13. The method of claim 1, further comprising: broadcasting an
identifier for a list of WLAN identifiers that is valid for a
particular area.
14. The method of claim 1, further comprising: creating a list of
WLAN identifiers for use by a mobile device in an access network
selection and/or traffic steering procedure.
15. The method of claim 14, further comprising: creating an
identifier for the list of WLAN identifiers, the identifier
comprising a version number and/or hash value.
16. A network node for use in a communication network, the network
node comprising: radio circuitry configured to communicate with a
mobile device; and processing circuitry operatively coupled to the
radio circuitry and configured to: determine whether a list of WLAN
identifiers stored in the mobile device is valid; and send a list
of WLAN identifiers to the mobile device, via the radio circuitry,
in response to determining that the list of WLAN identifiers stored
in the mobile device is not valid.
17. The network node of claim 16, wherein the processing circuitry
is configured to send an identifier for the list of WLAN
identifiers to the mobile device.
18. The network node of claim 16, wherein each of the WLAN
identifiers in the list is a service set identification (SSID), or
a basic SSID (BSSID), or an extended SSID (ESSID), or a homogenous
ESSID (HESSID), or a HotSpot 2.0 identifier.
19. The network node of claim 16, where the processing circuitry is
further configured to: receive an indication of the capability of
the mobile device to receive a list of WLAN identifiers from the
mobile device; and send the list of WLAN identifiers in response to
the received indication indicating that the mobile device is
capable of receiving a list of WLAN identifiers.
20. A computer program product having computer readable code
embodied therein, with the computer readable code being configured
such that, on execution by a suitable computer or processing unit
of a network node, the computer or processing unit is caused to:
determine whether a list of WLAN identifiers stored in a mobile
device is valid; and send a list of WLAN identifiers to the mobile
device, in response to determining that the list of WLAN
identifiers stored in the mobile device is not valid.
Description
TECHNICAL FIELD
[0001] The present disclosure is generally related to wireless
communications systems, and is more particularly related to
techniques for controlling the operation of mobile terminals with
respect to the use of multiple radio access technologies (RATs),
such as a wide area wireless communication technology and a
wireless local area network (WLAN) technology.
BACKGROUND
[0002] The wireless local-area network (WLAN) technology known as
"Wi-Fi" has been standardized by IEEE in the 802.11 series of
specifications (i.e., as "IEEE Standard for Information
technology--Telecommunications and information exchange between
systems. Local and metropolitan area networks--Specific
requirements. Part 11: Wireless LAN Medium Access Control (MAC) and
Physical Layer (PHY) Specifications"). As currently specified,
Wi-Fi systems are primarily operated in the 2.4 GHz or 5 GHz
bands.
[0003] The IEEE 802.11 specifications regulate the functions and
operations of the Wi-Fi access points or wireless terminals,
collectively known as "stations" or "STA," in the IEEE 802.11,
including the physical layer protocols, Medium Access Control (MAC)
layer protocols, and other aspects needed to secure compatibility
and inter-operability between access points and portable terminals.
Because Wi-Fi is generally operated in unlicensed bands,
communication over Wi-Fi may be subject to interference sources
from any number of both known and unknown devices. Wi-Fi is
commonly used as wireless extensions to fixed broadband access,
e.g., in domestic environments and in so-called hotspots, like
airports, train stations and restaurants.
[0004] Recently, Wi-Fi has been subject to increased interest from
cellular network operators, who are studying the possibility of
using Wi-Fi for purposes beyond its conventional role as an
extension to fixed broadband access. These operators are responding
to the ever-increasing market demands for wireless bandwidth, and
are interested in using Wi-Fi technology as an extension of, or
alternative to, cellular radio access network technologies.
Cellular operators that are currently serving mobile users with,
for example, any of the technologies standardized by the
3rd-Generation Partnership Project (3GPP), including the
radio-access technologies known as Long-Term Evolution (LTE),
Universal Mobile Telecommunications System (UMTS)/Wideband
Code-Division Multiple Access (WCDMA), and Global System for Mobile
Communications (GSM), see Wi-Fi as a wireless technology that can
provide good additional support for users in their regular cellular
networks.
[0005] As used herein, the term "operator-controlled Wi-Fi"
indicates a Wi-Fi deployment that on some level is integrated with
a cellular network operator's existing network, where the
operator's radio access network(s) and one or more Wi-Fi wireless
access points may even be connected to the same core network (CN)
and provide the same or overlapping services. Currently, several
standardization organizations are intensely active in the area of
operator-controlled Wi-Fi. In 3GPP, for example, activities to
connect Wi-Fi access points to the 3GPP-specified core network are
being pursued. In the Wi-Fi alliance (WFA), activities related to
certification of Wi-Fi products are undertaken, which to some
extent is also driven from the need to make Wi-Fi a viable wireless
technology for cellular operators to support high bandwidth
offerings in their networks. In these standardization efforts, the
term "Wi-Fi offload" is commonly used and indicates that cellular
network operators seek means to offload traffic from their cellular
networks to Wi-Fi, e.g., during peak-traffic-hours and in
situations when the cellular network needs to be off-loaded for one
reason or another, e.g., to provide a requested quality-of-service,
to maximize bandwidth, or simply for improved coverage.
[0006] Using Wi-Fi/WLAN (the two terms are used interchangeably
throughout this document) to offload traffic from the mobile
networks is becoming more and more interesting from both the
operator's and end user's points of view. Some of the reasons for
this tendency are: [0007] Additional frequency: by using Wi-Fi,
operators can access an additional 85 MHz of radio bandwidth in the
2.4 GHz band and another (close to) 500 MHz in the 5 GHz band.
[0008] Cost: From the operator's point of view, Wi-Fi uses
unlicensed frequency that is free of charge. On top of that, the
cost of Wi-Fi Access Points (APs), both from capital expense
(CAPEX) and operational expenses (OPEX) aspects, is considerably
lower than that of a 3GPP base station (BS)/enhanced NodeB (eNB).
Operators can also take advantage of already deployed APs that are
already deployed in hotspots such as train stations, airports,
stadiums, shopping malls, etc. Most end users are also currently
used to having Wi-Fi for free at home (as home broadband
subscriptions are usually flat rate) and public places. [0009]
Terminal support: Many User Equipments (UEs), including virtually
all smartphones, and other portable devices currently available in
the market, support Wi-Fi. In the Wi-Fi world, the term Station
(STA) is used instead of UE, and as such the terms UE, STA and
terminal/mobile terminal are used interchangeably in this document.
[0010] High data rate: Under low interference conditions and
assuming the user device is close to the Wi-Fi AP, Wi-Fi can
provide peak data rates that outshine that of current mobile
networks (for example, theoretically up to 600 Mbps for IEEE
802.11n deployments with MIMO (Multiple Input Multiple
Output)).
[0011] For a wireless operator, offering a mix of two technologies
that have been standardized in isolation from each other raises the
challenge of providing intelligent mechanisms for co-existence. One
area that needs these intelligent mechanisms is connection
management.
[0012] As noted above, many of today's portable wireless devices
(referred to hereinafter as "user equipments" or "UEs") support
Wi-Fi in addition to one or several 3GPP cellular technologies. In
many cases, however, these terminals essentially behave as two
separate devices, from a radio access perspective. The
3GPP-specified radio access network (RAN) and the UE-based modems
and protocols that are operating pursuant to the 3GPP
specifications are generally unaware of the wireless access Wi-Fi
protocols and modems that may be simultaneously operating pursuant
to the 802.11 specifications. Techniques for coordinated control of
these multiple radio-access technologies are needed.
[0013] In the study item 3GPP TR 37.834 "Study on WLAN/3GPP Radio
Interworking v1.0.0 (2013 August) a solution is proposed for
providing control of UE access network selection between 3GPP and
WLAN in the 3GPP RAN. In this solution (described in Section 6.1.2)
rules for when the UE can or should offload traffic to the WLAN is
specified in RAN specifications. The RAN provides (through
dedicated and/or broadcast signaling) thresholds which are used in
the rules.
[0014] This solution is applicable to UEs in RRC IDLE and RRC
CONNECTED states for E-UTRAN, UE IDLE mode for UTRAN and CELL_FACH,
CELL_PCH, URA_PCH and CELL_DCH states for UTRAN).
[0015] This solution consists of the steps shown in FIG. 1. For the
signaling procedure in FIG. 1, each step is elaborated below.
Step 1:
[0016] The RAN (e.g. eNB) provides parameters to the UE through
dedicated signaling and/or broadcast signaling.
Step 2:
[0017] The UE follows the RAN rules, defined in 3GPP RAN
specifications, to perform bi-directional offloading between WLAN
and 3GPP. User preference should take precedence.
[0018] An example Rule is:
TABLE-US-00001 if (measured_metricA < threshold1) &&
(measured_metricB > threshold2) { steerTrafficToWLAN( ); } else
if (measured_metricA > threshold3) || (measured_metricB <
threshold4) { steerTrafficTo3gpp( ); }
[0019] In addition, if the UE has been configured with access
network discovery and selection function (ANDSF) rules, the ANDSF
rules should not be broken.
SUMMARY
[0020] A problem with this and similar solutions is that currently
there is no way for the RAN or a mobility management entity (MME)
in the core network (CN) to indicate which WLANs should be
candidates for RAN-controlled WLAN selection. This means that the
UE either would apply RAN thresholds etc. for all WLANs, or a
suitable list of WLAN identities needs to be configured by ANDSF or
by the end user.
[0021] However, using all RAN thresholds for all WLANs is most
likely not desired from an end user point of view since the end
user might want to connect to private WLANs (which are cheaper for
the end user to use) regardless of RAN thresholds.
[0022] Also, relying on ANDSF or the end user will not be efficient
in case the list of WLANs changes (e.g. due to terminal mobility).
It is also envisaged that the solution should work without
requiring ANDSF.
[0023] Thus, techniques described herein introduce a method for the
RAN or MME (or other node in the core network (CN)) to send the UE
a list of WLAN identifiers used for RAN controlled WLAN access
selection and traffic steering.
[0024] Furthermore, mechanisms are introduced where the UE can
indicate to the RAN (for example via a core network node) or MME if
it has previously received such a list, which can avoid the need to
transmit the list every time the UE connects to the network.
[0025] It will be appreciated that these lists of WLAN identifiers
are not limited to use in the RAN-controlled WLAN access selection
solution described above, and they can be used by UEs in other
access network selection/traffic steering solutions that are
controlled by the network (e.g. RAN or MME) or by the UE.
[0026] Further embodiments of these techniques include optional
mechanisms for: [0027] the UE to indicate that it is capable of
receiving the WLAN list (e.g. as a part of the UE radio or network
capabilities). [0028] the UE to indicate to the RAN or MME a
version number or hash of the current WLAN list it has stored.
[0029] the RAN or MME to determine if the list of WLAN identifiers
stored in the UE is up to date, or if a new list overwriting or
modifying the existing list should be sent to the UE. [0030] the UE
to remove the current list of WLAN identifiers due to some mobility
or connectivity event (e.g. that the UE moves to another cell,
tracking area, etc., that the UE move to idle or detached state).
[0031] the UE to indicate to the RAN that it does not have any
stored WLAN identifiers list due to some mobility or connectivity
event (e.g. that the UE moves to another cell, tracking area, etc.,
that the UE moves to an idle or detached state). [0032] the network
to broadcast on the cell broadcast channel (or send in a dedicated
message) an identifier of the WLAN list valid in the current area
(cell, tracking area, PLMN). [0033] the UE to compare a received
identifier of the WLAN list to the one or more stored WLAN list
with associated identifiers. [0034] the UE to request the current
valid WLAN list from the network when the current stored list(s) do
not match the current WLAN list indicated by the network.
[0035] These techniques provide the advantage that it is possible
for the RAN to send out a list of WLAN identifiers used for
RAN-controlled access selection and traffic steering in a dynamic
and efficient way, avoiding the need to rely on higher layer
mechanisms.
[0036] Example embodiments of some of the techniques disclosed
herein are detailed below. However, it should be understood that
the list of example embodiments is not intended to be an exhaustive
representation of the embodiments disclosed herein.
[0037] According to a first specific aspect, there is provided a
method of operating a mobile device in a communication network, the
method comprising receiving a list of wireless local area network,
WLAN, identifiers from the communication network.
[0038] In a preferred embodiment, the step of receiving a list of
WLAN identifiers further comprises receiving an identifier for the
list of WLAN identifiers.
[0039] In some embodiments, the identifier for the list of WLAN
identifiers comprises a version number and/or a hash value.
[0040] In some embodiments, each of the WLAN identifiers in the
list is a service set identification, SSID, a basic SSID, BSSID, an
extended SSID, ESSID, a homogenous ESSID, HESSID, or HotSpot
2.0.
[0041] In some embodiments, the method further comprises the step
of using the received list of WLAN identifiers in an access network
selection and/or traffic steering procedure.
[0042] In some embodiments, the method further comprises the step
of sending an indication of the capability of the mobile device to
receive a list of WLAN identifiers to the network.
[0043] In some embodiments, the method further comprises the step
of storing the received list of WLAN identifiers.
[0044] In some embodiments, the method further comprises the step
of sending an identifier for the stored list of WLAN identifiers to
the network.
[0045] In some embodiments, the method further comprises the step
of removing the stored list of WLAN identifiers following a
mobility event, a connectivity event or on expiry of a validity
timer for the stored list.
[0046] In some embodiments, the method further comprises the step
of sending an indication to the network that the mobile device does
not have a stored list of WLAN identifiers, or requires a new list
of WLAN identifiers, following a mobility event, a connectivity
event or on expiry of a validity timer for the stored list.
[0047] In some embodiments, the method further comprises the step
of receiving an identifier for a list of WLAN identifiers that is
valid for the area in which the mobile device is located.
[0048] In some embodiments, the method further comprises the step
of comparing the received identifier to an identifier for the
received list of WLAN identifiers and requesting a list of WLAN
identifiers valid for the area in which the mobile device is
located, if the received identifier does not match the identifier
for the received list of WLAN identifiers.
[0049] In some embodiments, the step of receiving a list of WLAN
identifiers comprises receiving the list from a radio access
network, RAN, node, such as a base station or eNB, or a core
network node, such as a mobility management entity, MME.
[0050] In some embodiments, the step of receiving a list of WLAN
identifiers comprises receiving the list in radio resource control,
RRC, or non-access stratum, NAS, signaling.
[0051] According to a second aspect, there is provided a mobile
device for use in a communication network, the mobile device being
configured to receive a list of wireless local area network, WLAN,
identifiers from the communication network.
[0052] In some embodiments, the mobile device is further configured
to use the received list of WLAN identifiers in an access network
selection and/or traffic steering procedure.
[0053] In some embodiments, the mobile device comprises one or more
transceiver units configured to communicate with a wide area
network, such as a 3GPP-specified network and a wireless local area
network, WLAN, such as a Wi-Fi network.
[0054] Further embodiments of the mobile device are contemplated
corresponding to the method embodiments given above.
[0055] According to a third aspect, there is provided a method of
operating a network node in a communication network, the method
comprising sending a list of wireless local area network, WLAN,
identifiers to a mobile device.
[0056] In a preferred embodiment the step of sending a list of WLAN
identifiers further comprises sending an identifier for the list of
WLAN identifiers to the mobile device.
[0057] In some embodiments, the identifier for the list of WLAN
identifiers comprises a version number and/or a hash value.
[0058] In some embodiments, each of the WLAN identifiers in the
list is a service set identification, SSID, a basic SSID, BSSID, an
extended SSID, ESSID, a homogenous ESSID, HESSID, or HotSpot
2.0.
[0059] In some embodiments, the list of WLAN identifiers is for use
by the mobile device in an access network selection and/or traffic
steering procedure.
[0060] In some embodiments, the method further comprises the steps
of receiving an indication of the capability of the mobile device
to receive a list of WLAN identifiers from the mobile device and
sending the list of WLAN identifiers in response to the received
indication indicating that the mobile device is capable of
receiving a list of WLAN identifiers.
[0061] In some embodiments, the method further comprises the steps
of receiving an identifier for a list of WLAN identifiers stored in
the mobile device from the mobile device, determining if the list
of WLAN identifiers stored in the mobile device is valid and
sending the list of WLAN identifiers to the mobile device if it is
determined that the list of WLAN identifiers stored in the mobile
device is not valid.
[0062] In some embodiments, the step of determining if the list of
WLAN identifiers stored in the mobile device is valid comprises
determining if the list of WLAN identifiers is valid for the area
in which the mobile device is located.
[0063] In some embodiments, the method further comprises the steps
of receiving a request for a list of WLAN identifiers from the
mobile device and sending the list of WLAN identifiers to the
mobile device in response to the received request.
[0064] In some embodiments, the method further comprises the steps
of receiving an indication from the mobile device that the mobile
device does not have a stored list of WLAN identifiers and sending
the list of WLAN identifiers to the mobile device in response to
the received indication.
[0065] In some embodiments, the method further comprises the step
of determining whether the mobile device has a valid list of WLAN
identifiers stored therein following a mobility event or a
connectivity event by the mobile device.
[0066] In some embodiments, the step of determining whether the
mobile device has a valid list of WLAN identifiers comprises
comparing the identifier for a valid list of WLAN identifiers to an
identifier of a list of WLAN identifiers previously sent to the
mobile device.
[0067] In some embodiments, the step of determining whether the
mobile device has a valid list of WLAN identifiers comprises
comparing the identifier for a valid list of WLAN identifiers to an
identifier of a list of WLAN identifiers received from the mobile
device as part of the mobility event or connectivity event
signaling.
[0068] In some embodiments, the method further comprises the step
of broadcasting an identifier for a list of WLAN identifiers that
is valid for a particular area.
[0069] In some embodiments, the method further comprises the step
of creating a list of WLAN identifiers for use by a mobile device
in an access network selection and/or traffic steering
procedure.
[0070] In some embodiments, the method further comprises the step
of creating an identifier for the list of WLAN identifiers, the
identifier comprising a version number and/or hash value.
[0071] In some embodiments, the network node is a radio access
network, RAN, node, such as a base station or eNB, or a core
network node, such as a mobility management entity, MME.
[0072] In some embodiments, the step of sending a list of WLAN
identifiers comprises sending the list in radio resource control,
RRC, or non-access stratum, NAS, signaling.
[0073] According to a fourth aspect, there is provided a network
node for use in a communication network, the network node being
configured to send a list of wireless local area network, WLAN,
identifiers to a mobile device.
[0074] According to a preferred embodiment, the network node is a
radio access network, RAN, node, such as a base station or eNB, or
a core network node, such as a mobility management entity, MME.
[0075] Further embodiments of the network node are contemplated
corresponding to the preceding method embodiments.
[0076] Also contemplated are computer program products having
computer readable code embodied therein, with the computer readable
code being configured such that, on execution by a suitable
computer or processing unit, the computer or processing unit is
caused to perform any of the method embodiments described
above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0077] Exemplary embodiments of the techniques introduced in this
document are described below with reference to the following
figures, in which:
[0078] FIG. 1 is a signaling diagram illustrating a technique for
network controlled access selection and traffic steering;
[0079] FIG. 2 is a diagram of a wireless terminal and a Wi-Fi
access point;
[0080] FIG. 3 illustrates a portion of the LTE radio access network
and controller nodes;
[0081] FIG. 4 illustrates a network in which LTE radio access parts
and a Wi-Fi wireless access point are both connected to the same
core network node;
[0082] FIG. 5 is a block diagram of an exemplary wireless device
capable of communicating both over a 3GPP-specified access
technology and a WLAN;
[0083] FIG. 6 is a flow chart illustrating an exemplary method of
operating a network node according to the disclosed techniques;
[0084] FIG. 7 is a flow chart illustrating an exemplary method of
operating a mobile device according to the disclosed
techniques;
[0085] FIG. 8 is a set of flow charts illustrating the operation of
a mobile device and two separate RAN nodes according to an
exemplary embodiment;
[0086] FIG. 9 is a set of flow charts illustrating the operation of
a mobile device and a core network node according to another
exemplary embodiment;
[0087] FIG. 10 is a block diagram of an exemplary network node;
[0088] FIG. 11 is a block diagram of an exemplary base station;
and
[0089] FIG. 12 is a block diagram of an exemplary mobile
device.
DETAILED DESCRIPTION
[0090] In the discussion that follows, specific details of
particular embodiments of the present techniques are set forth for
purposes of explanation and not limitation. It will be appreciated
by those skilled in the art that other embodiments may be employed
apart from these specific details. Furthermore, in some instances
detailed descriptions of well-known methods, nodes, interfaces,
circuits, and devices are omitted so as not obscure the description
with unnecessary detail. Those skilled in the art will appreciate
that the functions described may be implemented in one or in
several nodes. Some or all of the functions described may be
implemented using hardware circuitry, such as analog and/or
discrete logic gates interconnected to perform a specialized
function, application-specific integrated circuits (ASICs),
programmable logic arrays (PLAs), etc. Likewise, some or all of the
functions may be implemented using software programs and data in
conjunction with one or more digital microprocessors or general
purpose computers. Where nodes that communicate using the air
interface are described, it will be appreciated that those nodes
also have suitable radio communications circuitry. Moreover, the
technology can additionally be considered to be embodied entirely
within any form of computer-readable memory, including
non-transitory embodiments such as solid-state memory, magnetic
disk, or optical disk containing an appropriate set of computer
instructions that would cause a processor to carry out the
techniques described herein.
[0091] Hardware implementations of the present techniques may
include or encompass, without limitation, digital signal processor
(DSP) hardware, a reduced instruction set processor, hardware
(e.g., digital or analog) circuitry including but not limited to
application specific integrated circuit(s) (ASICs) and/or field
programmable gate array(s) (FPGA(s)), and (where appropriate) state
machines capable of performing such functions.
[0092] In terms of computer implementation, a computer is generally
understood to comprise one or more processors or one or more
controllers, and the terms computer, processor, and controller may
be employed interchangeably. When provided by a computer,
processor, or controller, the functions may be provided by a single
dedicated computer or processor or controller, by a single shared
computer or processor or controller, or by a plurality of
individual computers or processors or controllers, some of which
may be shared or distributed. Moreover, the term "processor" or
"controller" also refers to other hardware capable of performing
such functions and/or executing software, such as the example
hardware recited above.
[0093] The discussion that follows frequently refers to "UEs,"
which is the 3GPP term for end user wireless devices. It should be
appreciated, however, that the techniques and apparatus described
herein are not limited to 3GPP UEs, but are more generally
applicable to end user wireless devices (e.g., portable cellular
telephones, smartphones, wireless-enabled tablet computers, etc.)
that are useable in cellular systems. It should also be noted that
the current disclosure relates to (but is not limited to) end user
wireless devices that support both a wireless local area network
(WLAN) technology, such as one or more of the IEEE 802.11
standards, and a wide-area cellular technology, such as any of the
wide-area radio access standards maintained by 3GPP including LTE
and UMTS. End user devices are referred to in Wi-Fi document as
"stations," or "STA"--it should be appreciated that the term "UE"
as used herein should be understood to refer to a STA, and
vice-versa, unless the context clearly indicates otherwise.
[0094] FIG. 2 illustrates a wireless terminal UE 100 able to
communicate, using 802.11-specified protocols, with a Wi-Fi access
point 110. Downlink communication 120 is directed from the Wi-Fi
access point 110 to the UE 100, while uplink communication 130 is
directed from the UE 100 to the Wi-Fi access point 110. Note that
while the detailed embodiments discussed herein are described in
reference to the IEEE 802.11 standards commonly referred to as
"Wi-Fi," the techniques and apparatus described are not necessarily
limited to those standards, but may be applied more generally to
other wireless local area network (WLAN) technologies.
[0095] For the UE to find an access point to connect to, a beacon
signal is transmitted from the Wi-Fi access point. This beacon
signal indicates details about the access point (e.g. the service
set identification (SSID), if SSID broadcast is enabled) and
provides the UE with enough information to be able to send a
request for access. Accessing a Wi-Fi access point includes an
information exchange between UE 100 and Wi-Fi Access point 110,
including, for example, probe requests and responses, and
authentication requests and response. The exact content of these
sequences are omitted for clarity.
[0096] FIG. 3 illustrates a portion of the LTE radio access network
and controller nodes. The LTE network is more formally known as the
Evolved UMTS Terrestrial Radio Access Network (E-UTRAN), and
includes base stations 220, 230, 240, called enhanced NodeBs (eNBs
or eNodeBs), which provide the E-UTRA user plane and control plane
protocol terminations towards the User Equipment (UE). It should be
noted that even though LTE is used as an example of a 3GPP radio
access technology (RAT) herein, the procedures described herein can
be applied to other wide-area RATs, including (but not limited to)
other 3GPP RATs such as UMTS.
[0097] The eNBs are interconnected with each other by means of the
X2 interface 250, 252, 254. The eNBs are also connected by means of
the S1 interface 260, 262, 264, 266 to the Evolved Packet Core
(EPC), and more specifically to Mobility Management Entities (MMEs)
200, 210, by means of the S1-MME interface, and to the Serving
Gateway (S-GW) 200, 210 by means of the S1-U interface. The S1
interface supports many-to-many relation between MMEs/S-GWs and
eNBs.
[0098] The eNB hosts functionalities such as Radio Resource
Management (RRM), radio bearer control, admission control, header
compression of user plane data towards serving gateway, and routing
of user plane data towards the serving gateway. The MME is the
control node that processes the signaling between the UE and the
core network. The main functions of the MME are related to
connection management and bearer management, which are handled via
Non Access Stratum (NAS) protocols. The S-GW is the anchor point
for UE mobility, and also includes other functionalities such as
temporary downlink (DL) data buffering while the UE is being paged,
packet routing and forwarding the right eNB, gathering of
information for charging and lawful interception. A packet data
network (PDN) Gateway (P-GW), which is not shown in FIG. 3, is the
node responsible for UE IP address allocation, as well as for
Quality-of-Service (QoS) enforcement.
[0099] FIG. 4 illustrates a network where the LTE radio access
parts 320, 322 and a Wi-Fi wireless access point 310 are both
connected to the same P-GW 340. A UE 300 is capable of being served
both from the Wi-Fi Access Point 310 and the LTE eNBs 320, 322.
FIG. 4 illustrates one possible way of connecting a Wi-Fi access
network to the same core network as the 3GPP-specified access
network. It should be noted that the presently disclosed techniques
are not restricted to scenarios where the Wi-Fi access network is
connected in this way; scenarios where the networks are more
separate, e.g., as illustrated in FIGS. 2 and 3, are also possible
scenarios.
[0100] There can be an interface 370 between the Wi-Fi and 3GPP
domains, whereby the two networks can exchange information that can
be used to facilitate the steering of traffic over the right
network. One example of such information exchanged via the
interface 370 is load conditions in the two networks. The two
networks can also exchange information with regard to the context
of the UE 300, so that each can be aware of whether the UE is being
served by the other network, as well as some details of the
connection over the other network (e.g. traffic volume, throughput,
etc. . . . ).
[0101] It should be noted that an access-point controller (AC)
functionality exists in the Wi-Fi domain that controls the Wi-Fi
AP. This functionality, though not depicted in the figure for the
sake of clarity, can be physically located in 310, 340 or it can be
another separate physical entity.
[0102] FIG. 5 illustrates an exemplary UE 400 capable of
communicating both over a 3GPP-specified access technology and also
over an 802.11 Wi-Fi specified access technology. For illustrative
purposes, the processing and modem related to the Wi-Fi parts 410
are separated from the processing and modem related to the 3GPP
parts 420. It will be appreciated that the implementation of these
parts could be integrated on the same hardware unit, or can be
carried out using physically distinct hardware and/or
hardware-software combinations.
[0103] As discussed above, a problem with known solutions for
allowing RAN controlled access network selection and/or traffic
steering is that currently there is no way for the RAN or a
mobility management entity (MME) in the core network (CN) to
indicate which WLANs should be candidates for RAN-controlled WLAN
selection. However, techniques described herein provide that the
RAN or MME (or other node in the core network (CN)) sends the UE a
list of WLAN identifiers used for WLAN access selection and traffic
steering.
[0104] FIG. 6 illustrates a method of operating a network node
according to these techniques. The network node performing the
method in FIG. 6 can be a node in the RAN, such as a base station,
eNB or RNC, or a node in the core network, such as an MME. In a
first optional step, step 500, the network node creates a WLAN list
for use in an access network selection/traffic steering procedure
that is to be performed by a mobile device (UE).
[0105] The `WLAN list` or `list of WLAN identifiers`, as used
herein, is a list of zero or more identifiers for WLAN access
points that the mobile device is allowed to consider when
performing access network selection or traffic steering. The APs
included in a WLAN list can be any APs in a specific region (e.g. a
city/town). This means that the APs included in a WLAN list can
include APs not in the coverage area of the cell in which the
mobile device is located. In this way, continuous updating of the
WLAN list can be avoided. In some embodiments each UE in a region
receives the same list, but in other embodiments it is possible to
create and send UE-specific WLAN lists (or WLAN lists for specific
categories of UEs, such as for UEs with a specific subscription
level). In some embodiments, a specific WLAN list can be provided
(for example a WLAN list with zero entries) if the network operator
wishes to prevent the UE from accessing or switching traffic to the
WLAN.
[0106] The identifier for each WLAN access point (AP) included in
the WLAN list can be provided in any suitable form, and may
comprise, for example, the service set identification (SSID), the
basic SSID (BSSID), the extended SSID (ESSID), the homogenous ESSID
(HESSID) or HotSpot 2.0. Those skilled in the art will be aware of
other forms of information that identify a WLAN AP and that can be
included in the WLAN list in addition to or in place of any of the
above identifiers.
[0107] In some embodiments, step 500 also comprises determining a
version number or identifier and assigning it to the WLAN list. It
will be appreciated that instead of, or in addition to, a version
number, a hash for the WLAN list can be assigned/created which can
be used to identify the WLAN list. It will in some places in this
document only be explained how version numbers are used, but it
should be appreciated that, unless otherwise stated, hashes can be
used in addition to or instead of a version number or
identifier.
[0108] Once the WLAN list has been created in step 500 it is sent
to the mobile device in step 510. The WLAN list may be sent to the
UE along with the version number, hash or any other suitable WLAN
list identifier.
[0109] In some cases the WLAN list can be created in step 500 and
stored in a memory module of the network node until it is required
to be sent to a mobile device.
[0110] FIG. 7 illustrates a corresponding method of operating a
mobile device. In step 600, the mobile device receives a WLAN list
from a network node. As noted above, the WLAN list may be sent to
the mobile device along with a version number, hash or other
identifier for the WLAN list.
[0111] The mobile device stores the WLAN list (and WLAN list
identifier if present), and, optionally, uses the received WLAN
list in an access network selection/traffic steering procedure
(step 610).
Methods for Providing WLAN Lists to Mobile Devices
[0112] This section will describe alternative methods for providing
the WLAN list to mobile devices (UEs). As noted above, WLAN lists
can be created and/or maintained in the RAN and/or the core
network. In the examples below the mobility management entity (MME)
will be used as an example of a suitable core network node.
However, it should be appreciated that this is just an example and
it is possible that some other core network node is involved in the
provisioning of applicable WLAN lists to the UE.
[0113] WLAN List Maintained in RAN
[0114] In one set of embodiments, the RAN creates the list of WLANs
for a UE and assigns to the list a version number.
[0115] If the WLAN lists are residing in the RAN, the MME (or other
core network node) may be aware of an identifier of the WLAN list
residing in the RAN and know which RAN nodes (e.g. eNBs) have the
same WLAN lists. For example eNB A and eNB B may maintain the same
WLAN list (for example WLAN list X), while eNB C maintains another
WLAN list (for example WLAN list Y). The MME could then know that
eNB A and eNB B maintains a WLAN list with index X while eNB C
maintains a WLAN list with index Y.
[0116] The benefit of RAN-maintained WLAN lists is that as the RAN
is aware of the WLANs in the WLAN lists, the RAN has the option to
apply different behaviour to different WLANs. If the RAN is not
aware of which WLANs the UE is considering in the access network
selection or traffic steering, the RAN may not be able to know
which WLANs are operator WLANs and which WLANs are non-operator
WLANs (e.g. private WLANs), at least without some additional
configuration.
[0117] WLAN List Maintained in MME
[0118] In one embodiment the MME creates the list of WLANs for a UE
and assigns to the list a version number or hash. The MME can
signal the WLAN list to the UE, for example by NAS signalling
and/or by delivering it to the RAN using e.g. S1 signalling, where
the RAN will deliver it to the UE using e.g. radio resource control
(RRC) signalling.
Triggers for WLAN List Provisioning
[0119] An update to a WLAN list held or stored by a mobile device
(UE) (with `update` meaning that the network sends the UE a new
WLAN list) can be triggered in a number of different ways. WLAN
list update can be triggered by, for example, any of the following
three entities; UE, RAN or MME. Examples of how this can be done is
illustrated in the subsections below.
[0120] UE Triggered WLAN List Provisioning
[0121] In this approach the UE will trigger an update of its stored
WLAN list.
[0122] In one embodiment the UE can trigger such an update upon
entering a new tracking area (or Routing Area in UTRAN or Location
Area in GSM), i.e. if the tracking area code (TAC) for the current
cell is different from the TAC the UE currently has. It should be
noted that the UE may have multiple tracking areas (such as in
UMTS), in which case the UE may not trigger a WLAN list update if
the tracking area for the current cell is equivalent to the
tracking area which the UE has in its tracking area list.
[0123] In one embodiment a RAN node (e.g. eNB) will broadcast or
send in a dedicated message a version number and/or hash
corresponding to the WLAN list that should be used by the UE when
the UE is associated with that eNB. This version number and/or hash
can be used by the UE to determine if the UE has the correct WLAN
list. For example, if the UE has a WLAN list with version number X
and the RAN node with which the UE is associated indicates a WLAN
list with version number Y is required, the UE would know that the
WLAN list the UE maintains is not valid/up to date for that
eNB.
[0124] If the UE-triggered approach is applied the UE will request
the entity that maintains/provides the WLAN lists to obtain a valid
WLAN list. Where the RAN is the entity that maintains/provides the
WLAN lists, the UE can send a message to the RAN indicating that
the UE needs a valid WLAN list. The RAN may then signal the WLAN
list to the UE in a response message. These messages can, for
example, be radio resource control (RRC) messages; although other
types of messages could be used instead.
[0125] Where the MME is the entity that maintains/provides the WLAN
lists, the UE can send a message to the MME indicating that the UE
needs a valid WLAN list. The MME may then signal the WLAN list to
the UE in a response message. These messages can, for example, be
NAS messages, although other types of messages could be used
instead.
[0126] In other embodiments, the UE could trigger an update
to/replacement of the WLAN list on expiry of a WLAN list validity
timer or on the occurrence of some other similar event. The value
of the WLAN list validity timer could be predefined in the UE or it
could be signalled by a network node to the UE (for example in
conjunction with the sending of the WLAN list).
[0127] RAN Triggered WLAN List Provisioning
[0128] In this approach the eNB will trigger an update of a WLAN
list stored in a UE.
[0129] In one embodiment the RAN will trigger an update on
detecting that the UE has initiated a NAS procedure (e.g. a NAS
service request, a tracking area update or a NAS attach). The
knowledge of when the UE performs these procedures could be
indicated by the UE or by the MME, or it could be detected
implicitly based on the amount of signalling or cause values used,
etc.
[0130] In one embodiment the UE indicates to the RAN (for example
in an RRC message) the version number of the WLAN list the UE has
and the RAN could, based on this knowledge, trigger an update of
the UE's WLAN list. If the UE has not yet received a WLAN list, the
UE could indicate this to the RAN node, for example by sending a
message to the RAN node that contains a predefined value that
indicates this status. Where the UE sends the version number to the
RAN node, this can be done in a number of different ways (note that
one or more of these alternatives may be used): [0131] Upon RAN
request. [0132] Upon occurrence of some event, such as initial
association, tracking area update, handover, establishment of RRC
connection to the RAN node, etc. [0133] Upon expiration of a
timer.
[0134] If the RAN creates/maintains the WLAN list (as described
above) the RAN could generate an up to date WLAN list for the UE
and send the WLAN list in a message (for example an RRC message) to
the UE.
[0135] If the MME is the entity which creates/maintains the WLAN
list (also as described above) the RAN can indicate to the MME that
the UE's WLAN list needs updating. It is also possible for the MME
to generate the WLAN list and provide this WLAN list to the RAN,
and for the RAN to send the WLAN list to the UE in an RRC (or
similar) message.
[0136] In one embodiment it is possible to trigger the sending of
the new WLAN list to the UE if the UE enters a RRC connected state
or performs a handover and the RAN (or target RAN) receives an
indication in the UE capabilities that the UE supports receiving a
WLAN list.
[0137] In another embodiment the RAN can send the new WLAN list to
one or more UEs if the WLAN list maintained by the RAN has changed
(for example if a new or updated WLAN list has been provided by an
Operation and Maintenance system of the RAN).
[0138] MME Triggered WLAN List Provisioning
[0139] In this approach the MME will trigger an update to a WLAN
list stored in a UE.
[0140] In one embodiment the UE indicates the version number of its
stored WLAN list to the MME, and the MME will determine if the WLAN
list is up to date. If the UE has not yet received a WLAN list, the
UE could indicate this to the MME, for example by sending a message
to the MME that contains a predefined value that indicates this
status. If the MME determines that the WLAN list for the UE is not
up to date (including if the UE does not yet have a WLAN list) the
MME may trigger a WLAN list update. If the WLAN list is up to date
the MME may refrain from triggering a WLAN list update.
[0141] The UE may indicate to the MME which WLAN list version it
has upon: [0142] Tracking area update (it will be appreciated that
a similar concept to tracking areas is applicable in other
communication technologies) [0143] Expiration of a timer. [0144]
Explicit request from a network node. The node may be the MME
itself or some other network node, e.g. a RAN node.
[0145] In one embodiment the MME can determine which WLAN list
version the UE has by determining which WLAN list/lists the UE has
received previously, and trigger a WLAN list update when the UE's
WLAN list is not valid. For example, if the MME provides WLAN list
A in tracking areas X and Y and WLAN list B in tracking area Z, the
MME will be able to determine that if a UE has been provisioned
with a WLAN list in tracking area X, the UE can continue to use
this WLAN list when it is in tracking area Y. However, the MME will
know if the UE enters tracking area Z, a WLAN list provisioning
will need to be triggered since the UE should be using WLAN list
B.
[0146] In the above embodiment, if the UE's current WLAN list was
provided by another entity in the network (e.g. another MME) then
the MME may be able to know which WLAN list was provided through
coordination between the MME and the other entity (e.g. the other
MME).
[0147] If the MME is the entity which maintains the WLAN list (as
described above) the MME could generate an up to date WLAN list for
the UE and send the WLAN list in a message (for example in a NAS
message) to the UE. Alternatively, the MME can generate the WLAN
list and provide the list to the RAN, and the RAN can send the WLAN
list to the UE, for example in an RRC message.
[0148] If the RAN maintains the WLAN list (as described above) the
MME can indicate to the RAN that the UE's WLAN list needs updating.
The RAN node can then send an up to date WLAN list with the
associated version number to the UE.
[0149] In one embodiment it is possible for the MME to trigger the
sending of a new WLAN list to the UE if the UE enters a specific
state (e.g. EPS Mobility Management (EMM) Connected state) or
performs a handover and the RAN (or target RAN) receives an
indication in the UE capabilities that the UE supports receiving
the WLAN list.
[0150] In another embodiment the MME can send a WLAN list to one or
more UEs if the WLAN list has changed (e.g. if a new or updated
WLAN list has been provided by an Operation and Maintenance system
of the MME).
[0151] The flow charts in FIG. 8 illustrate a first exemplary
embodiment of the above techniques. Three flow charts are shown in
FIG. 8, the first (FIG. 8(a)) shows the method steps performed in a
UE, the second (FIG. 8(b)) shows the method steps performed in a
first node (denoted eNB1) in the RAN and the third (FIG. 8(c))
shows the method steps performed in a second node (denoted eNB2) in
the RAN.
[0152] In a first step (steps 700 and 720), a UE attaches to the
3GPP network, and specifically, eNB1.
[0153] The RAN node to which the UE connects (eNB1) creates a WLAN
list for the UE (if not already created) and assigns version number
X to the WLAN list, or retrieves a previously created WLAN list X
from a memory (step 722).
[0154] The RAN node (eNB1) sends the WLAN list with version number
X to the UE (step 724).
[0155] The UE receives this WLAN list with version number X (step
702) and stores it locally in the UE.
[0156] If an access network selection or traffic steering process
is or needs to be performed by the UE, the UE uses the received
WLAN list in this process (step 704).
[0157] Subsequently (steps 706 and 730), the UE performs a handover
to another 3GPP node (eNB2 in this example).
[0158] In this embodiment, when the UE performs the handover to
eNB2, the UE sends an indication of the version number, i.e. X, of
the WLAN list it received from the previous node (steps 708). The
UE then waits for a new WLAN list from eNB2 (if one is
required)--step 710. If no new WLAN list is received, the UE uses
the stored WLAN list X when an access network selection or traffic
steering procedure is performed (steps 712, 714). If a new WLAN
list is received (e.g. a WLAN list with version number Y), the UE
stores the new WLAN list (and optionally deletes WLAN list X from
memory). The UE then uses WLAN list Y when an access network
selection or traffic steering procedure is performed (step
716).
[0159] In step 732 the eNB2 receives the indication of the version
number of the WLAN list sent by the UE in step 708 and determines
whether the WLAN list stored in the UE is valid for use with eNB2
(step 734). If the WLAN list with version number X is valid in
eNB2, then it is not necessary for any new WLAN list to be sent to
the UE (step 736). However if WLAN list X is not valid for eNB2
(for example if WLAN list X does not appear on a list of valid WLAN
lists for eNB2 or does not match the WLAN list valid for eNB2, e.g.
WLAN list Y) then eNB2 creates a WLAN list Y for the UE (or
retrieves the WLAN list with identifier Y from a memory of the
eNB2), step 738, and sends the WLAN list to the UE (step 740). As
noted above, the UE receives the new WLAN list Y and uses this in
future access network selection or traffic steering procedures.
[0160] The flow charts in FIG. 9 illustrate a second exemplary
embodiment of the above techniques. Two flow charts are shown in
FIG. 9, the first (FIG. 9(a)) shows the method steps performed in a
UE, and the second (FIG. 9(b)) shows the method steps performed in
a node in the core network (e.g. the MME).
[0161] In a first step (steps 800 and 820), a UE attaches to the
3GPP network (e.g. a node in the RAN denoted eNB1).
[0162] In this embodiment, when the UE attaches to eNB1, the UE
sends an indication that it has not received a WLAN list to the MME
(step 802). This indication can be included in a message that is
sent during the NAS setup procedure, and can be indicated by a
predefined value which indicates that the UE has not received a
WLAN list. It should be appreciated that in this embodiment the UE
can send the indication that it has not received a WLAN list even
if the UE has a stored WLAN list, since in this embodiment it will
trigger the provision of an up to date WLAN list from the
network.
[0163] On receipt of this indication from the UE (step 822), the
MME creates a WLAN list for the UE (if not already created) and
assigns version number X to the WLAN list, or (if previously
created) retrieves WLAN list X from a memory (step 824). The MME
then sends the WLAN list X to the UE (steps 826).
[0164] The UE receives this WLAN list with version number X (step
804) and stores it locally in the UE. If an access network
selection or traffic steering process is or needs to be performed
by the UE (step 810), the UE uses the received WLAN list X in this
process.
[0165] If the UE subsequently moves to another tracking area, or
performs some other mobility or connectivity event, the UE will
perform a tracking area update (step 806).
[0166] If the UE performs a tracking area update, the MME will
determine what WLAN list version is stored in the UE (steps 828 and
830). In some embodiments, the MME can determine this from the
version number of the WLAN list last sent to the UE by the MME,
and/or from an indication of the WLAN list stored in the UE that
the UE signals during the tracking area update procedure, etc.
[0167] If it is determined that the WLAN list stored in the UE is
valid then no WLAN list update is needed (step 833). However if it
is determined that the WLAN list stored by the UE is not valid in
the tracking area to which the UE has moved, the MME creates (if
not yet created) a valid WLAN list for the new tracking area and
assigns a version number to it, or retrieves a previously created
WLAN list that is valid for the tracking area from a memory (step
834) and sends the WLAN list and the version number to the UE (step
836).
[0168] The UE receives the new WLAN list (step 808), stores it in a
memory and uses the WLAN list if an access network selection or
traffic steering process is or needs to be performed by the UE
(step 810).
Apparatus
[0169] Although the described solutions may be implemented in any
appropriate type of telecommunication system supporting any
suitable communication standards and using any suitable components,
network-based embodiments of the described solutions may be
implemented in one or more nodes of a radio access network (RAN),
such as a node in a 3GPP RAN network, such as LTE, or one or more
nodes of a core network (CN) in a 3GPP network. These RAN nodes
include, but are not limited to, an eNodeB in an LTE network, or a
base station or RNC in a UMTS network, and the CN nodes include,
but are not limited to, a mobility management entity (MME) in an
LTE network.
[0170] The network in which these techniques are implemented may
further include any additional elements suitable to support
communication between wireless devices or between a wireless device
and another communication device (such as a landline telephone).
Although the illustrated network nodes may represent a network
communication device that includes any suitable combination of
hardware and/or software, these network nodes may, in particular
embodiments, represent a device such as the example network node
900 illustrated in greater detail by FIG. 10. Similarly, although
the illustrated base station nodes (e.g., an eNB) may represent
network nodes that include any suitable combination of hardware
and/or software, these network nodes may, in particular
embodiments, represent devices such as the example network node
1000 illustrated in greater detail by FIG. 11.
[0171] As shown in FIG. 10, the example network node 900 includes
processing circuitry 920, a memory 930, and network interface
circuitry 910. In particular embodiments, some or all of the
functionality described above as being provided by a core network
node or a node in a RAN may be provided by the processing circuitry
920 executing instructions stored on a computer-readable medium,
such as the memory 930 shown in FIG. 10. Alternative embodiments of
the network node 900 may include additional components beyond those
shown in FIG. 10 that may be responsible for providing certain
aspects of the node's functionality, including any of the
functionality described above and/or any functionality necessary to
support the solutions described above.
[0172] As shown in FIG. 11, an example base station 1000 includes
processing circuitry 1020, a memory 1030, radio circuitry 1010, and
at least one antenna. The processing circuitry 1020 may comprise RF
circuitry and baseband processing circuitry (not shown). In
particular embodiments, some or all of the functionality described
above as being provided by a mobile base station, a radio network
controller, a base station controller, a relay node, a NodeB, an
enhanced NodeB, and/or any other type of mobile communications node
may be provided by the processing circuitry 1020 executing
instructions stored on a computer-readable medium, such as the
memory 1030 shown in FIG. 11. Alternative embodiments of the
network node 1000 may include additional components responsible for
providing additional functionality, including any of the
functionality identified above and/or any functionality necessary
to support the solution described above.
[0173] Several of the terminal-based techniques and methods
described above may be implemented using radio circuitry and
electronic data processing circuitry provided in a terminal. FIG.
12 illustrates features of an example terminal 1500 according to
several embodiments of the present invention. Terminal 1500, which
may be a UE configured for operation with an LTE network (E-UTRAN)
and that also supports Wi-Fi, for example, comprises a transceiver
unit 1520 for communicating with one or more base stations as well
as a processing circuit 1510 for processing the signals transmitted
and received by the transceiver unit 1520. Transceiver unit 1520
includes a transmitter 1525 coupled to one or more transmit
antennas 1528 and receiver 1530 coupled to one or more receiver
antennas 1533. The same antenna(s) 1528 and 1533 may be used for
both transmission and reception. Receiver 1530 and transmitter 1525
use known radio processing and signal processing components and
techniques, typically according to a particular telecommunications
standard such as the 3GPP standards for LTE. Note also that
transmitter unit 1520 may comprise separate radio and/or baseband
circuitry for each of two or more different types of radio access
network, such as radio/baseband circuitry adapted for E-UTRAN
access and separate radio/baseband circuitry adapted for Wi-Fi
access. The same applies to the antennas--while in some cases one
or more antennas may be used for accessing multiple types of
networks, in other cases one or more antennas may be specifically
adapted to a particular radio access network or networks. Because
the various details and engineering tradeoffs associated with the
design and implementation of such circuitry are well known and are
unnecessary to a full understanding of the techniques presented
herein, additional details are not shown here.
[0174] Processing circuit 1510 comprises one or more processors
1540 coupled to one or more memory devices 1550 that make up a data
storage memory 1555 and a program storage memory 1560. Processor
1540, identified as CPU 1540 in FIG. 12, may be a microprocessor,
microcontroller, or digital signal processor, in some embodiments.
More generally, processing circuit 1510 may comprise a
processor/firmware combination, or specialized digital hardware, or
a combination thereof. Memory 1550 may comprise one or several
types of memory such as read-only memory (ROM), random-access
memory, cache memory, flash memory devices, optical storage
devices, etc. Because terminal 1500 supports multiple radio access
networks, processing circuit 1510 may include separate processing
resources dedicated to one or several radio access technologies, in
some embodiments. Again, because the various details and
engineering tradeoffs associated with the design of baseband
processing circuitry for mobile devices are well known and are
unnecessary to a full understanding of the techniques described
herein, additional details are not shown here.
[0175] Typical functions of the processing circuit 1510 include
modulation and coding of transmitted signals and the demodulation
and decoding of received signals. In several embodiments of the
disclosed techniques, processing circuit 1510 is adapted, using
suitable program code stored in program storage memory 1560, for
example, to carry out one of the techniques described above for
access network selection. Of course, it will be appreciated that
not all of the steps of these techniques are necessarily performed
in a single microprocessor or even in a single module.
[0176] It will be appreciated by the person of skill in the art
that various modifications may be made to the above described
embodiments without departing from the scope of the presently
disclosed techniques. For example, it will be readily appreciated
that although the above embodiments are described with reference to
parts of a 3GPP network, embodiments will also be applicable to
like networks, such as a successor of the 3GPP network, having like
functional components. Therefore, in particular, the terms 3GPP and
associated or related terms used in the above description and in
the enclosed drawings and any appended claims now or in the future
are to be interpreted accordingly.
[0177] Examples of several embodiments have been described in
detail above, with reference to the attached illustrations of
specific embodiments. Because it is not possible, of course, to
describe every conceivable combination of components or techniques,
those skilled in the art will appreciate that the presently
disclosed techniques can be implemented in other ways than those
specifically set forth herein. The present embodiments are thus to
be considered in all respects as illustrative and not
restrictive.
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