WO2010037422A1

WO2010037422A1 - Optimizing andsf information provisioning for multiple-radio terminals

Info

Publication number: WO2010037422A1
Application number: PCT/EP2008/063264
Authority: WO
Inventors: Frank Pittmann
Original assignee: Nokia Siemens Networks Oy
Priority date: 2008-10-03
Filing date: 2008-10-03
Publication date: 2010-04-08
Also published as: EP2351426A1

Abstract

A network device of a communication network for provisioning access network information to an UE (User Equipment) is provided which is based on the Access Network Discovery and Selection Function (ANDSF) provided by the 3GPP. The network device comprises an interface to receive external information from at least one information provisioning device, a calculating device to determine provisioning information for the UE using the received external information, a storage device to store the determined provisioning information.

Description

DESCRIPTION

TITLE

Optimizing ANDSF information provisioning for multiple-radio terminals

The application relates to network discovery and network selection .

With increasing deployment of multitude wireless access systems, a need to develop sophisticated means for resource allocation and for handover control in a heterogeneous environment of the wireless access systems arises. Allocation mecha- nisms for heterogeneous resources are responsible for mapping mobile devices or User Equipments (UE) to different access technologies of the heterogeneous wireless environments. The mapping is based on traffic load conditions of radio access and of core network of the heterogeneous wireless environ- ments, on user application requirements, and on user geographic location without sacrificing user experiences of quality of service and of seamless service. Architectures of the heterogeneous wireless environments incorporate information from various sources that includes network functions in order to coordinate inter-working of the heterogeneous wireless environments.

An Access Network Discovery and Selection Function (ANDSF) is provided by document of 3GPP (Third Generation Partnership Project) TS 23.402 V8.3.0 (2008-09), "Architecture enhancements for non-3GPP accesses", Release 8, http : //www.3gpp . org/ftp/Specs/htmf1-info/23402.htm.

The ANDSF provides the UE with support for access system dis- covery and mobility between 3GPP and non-3GPP network accesses or between non-3GPP network accesses. The mobility support provides assistance data or network policies information about available network accesses for the UE such that the UE can scan for the network accesses and select the network access. A heterogeneous network environment can have 3GPP and non-3GPP network accesses or multiple non-3GPP network accesses. In this environment, 3GPP Evolved Packet Sys- tern (EPS) allows its network operator to influence the network access that the UE shall handover to when it is in an active mode or re-select when it is in an idle mode. Such multi-access Network Discovery and Selection (NWDS) functionality supports both single-radio terminal and multiple-radio terminals .

In the context of the 3GPP networks, a handover in general switches complete communication of all network traffic flows between available network accesses, such as a 3GPP network access to a non-3GPP network access, vice versa, or between non-3GPP network accesses.

A 3GPP SA2 architecture specification, Release 8, which is described at http://www.3gpp.org/tb/SA/SA2/SA2.htm, also pro- vides the ANDSF with a simple nature in that it does not have a roaming feature or any other network interface feature. Other specification work groups for CT (Core Network and Terminals) , CTl, and CT4 use the finalised architecture specification. Specification for the CT, the CTl, and the CT4 are shown in http://www.3gpp.org/tb/.

One of the thoughts of application is that information provisioning or supplying of information be improved by taking into account information provided by one or more network functions, such as SbH, or one or more network conditions, such as congestion, and not just information regarding UE current location, UE capabilities, or network operator policies. Moreover, the information provisioning should cope with dynamisms inherent in telecommunication networks, especially future mobile telecommunication networks.

The application provides a network device of a communication network. The network device operates in a 3GPP environment. The network device is also called a network entity. The communication network provides communication services for its users or subscribers. The communication network includes a wired communication access network and/or a wireless communi- cation access network for its users to access the communication network. The access network is also called network access .

The network device is intended for provisioning access net- work information to an UE (User equipment) . The access network information is provisioned or is supplied to the UE.

The UE provides a communication means for the user to communicate with the communication network. The communication can include voice signals or data packet signals. The access network information enables the UE to scan for the access network and to select the access network.

The network device comprises an interface for receiving ex- ternal information from one or more information provisioning devices. The interface allows the network device to exchange information with the information provisioning devices. The interface can comprise a Gx interface.

The information provisioning device has certain useful information that the network device does not have. The useful external information is provided to the network device such that the network device can use the received external information to improve it provisioning of information to the UE. The provisioning of information to the UE can be improved in that information that is not useful to the UE to scan for network access or to select for the network access are not provided to the UE. In other words, the information that is provisioned to the UE is limited in an efficient manner.

The limitation also allows a faster transfer of information between the network device and the UE as its transfer signal bandwidth is not fully used. It also allows the network de- vice to cope with network dynamisms or changes as the information provisioning device can provide information related to the network dynamisms to the network device such that the network device can cope or adapt with the network dynamisms.

In a sense, the information provisioning device act as a PDP (Policy Decision Point function) functional entity whilst the network device acts as a PEP (Policy Enforcement Point) entity.

The network device also comprises a calculating device to determine provisioning information for the UE using the received external information. The determination can decide or select information for provisioning to the UE using the re- ceived external information to meet certain network objective or policy. A network operator can derive or influence the determination. The calculating device can have determination algorithm for determining the provision of information to the UE.

The network device can also include a storage device to store the determined provisioning information for later use.

The UE can comprise at least one radio interface or at least one radio terminal for accessing the multiple network accesses. The multiple network accesses can comprise different radio network technologies.

The received external information can include network func- tion information, such as Service based Handover information, or network condition information, such as traffic congestion information. The network device can use the information, for example, to select network access.

The information provisioning device can comprise an entity for provisioning a PCRF (Policy Control and Charging Rules Function. The PCRF function is part of a PCC (Policy and Charging Control) architecture. The UE provided information can comprise UE current location information and UE capabilities information. The UE can use received determined provisioning information to scan for net- work access and to select the network access.

The determined provisioning information can also comprise a network operator policy. The network operator policy enables or assists the UE to decide on scanning or selecting of the network access.

This application provides a communication network that comprises one or more network devices. The communication network can include different network technologies.

This application provides a method for selectively accessing a communication network. The communication network can have different access network that comprises different access network technologies.

The method comprises the steps of receiving external information from the information-provisioning device by a network device via the interface. The network device in a pull mode can request the external information or the external informa- tion can be provided without any request or solicitation by the network device in a push mode.

The method also includes the step of determining information by the network device for provisioning to the UE using the received external information. The network device can also use other information, in addition to the received external information to determine the provisioning information.

The method also includes the step of sending the determined provisioning information to the UE.

In a pull mode, the method can comprise the further step of requesting for the external information by the network de- vice. This allows the network device to improve its information provisioning to the UE, as and when it needs the improvement .

Similarly, in a push mode, the method can include the further step of unsolicited sending of the external information to the network device. The external information is sent to the network device without the network device soliciting or requesting for the external information. A background program can trigger the sending of the external information. This provides for an automated transmission of external information, which can improve user experience of its network service .

In a special case, the method can comprise steps for the push mode as well as the steps of the pull mode.

The determined provisioning information for the UE can be stored in the network device for later use.

The UE can use the determined provisioning information to evaluate or to determine access network information. The determined provisioning information can have assistance data and network policy that the UE can use to determine the ac- cess network information.

The UE can use the determined access network information scanning for network accesses.

The method can comprise the further step of selecting network for accessing and the further step of accessing the selected network access.

The application also provides an enhanced Access Network Dis- covery Support Function (ANDSF) to improve information provisioning from the enhanced ANDSF to an UE (User Equipment) . The enhanced ANDSF also limits or restricts information that is provided the UE. The application also provides an implementation of an enhanced ANDSF for improving information provision to the UE using as an example a SbH (Service based Handover) network function to highlight its advantages.

A reference point (RP) is provided to enable the enhanced ANDSF to improve its information provisioning. The RP resides between the enhanced ANDSF and a Policy Decision Point (PDP) . The PDP can be a host for certain network functionalities, like the SbH function. It is reasonable to use the PDP since intelligent network functions are policy-based. They need decision engines to provide its service and finally to trigger enforcement of its network policies. The RP can be imple- mented between the enhanced ANDSF and the PDP. In this sense, the enhanced ANDSF also hosts or acts as a Policy Enforcement Point (PEP) .

The PDP has knowledge that can advantageously be used by the enhanced ANDSF to improve its information provisioning to the UE and thereby limits amount of information provided to the UE. The enhanced ANDSF can know about UE location and it can be guided by certain local network policies to share necessary information about all or certain available access net- works to the UE. The limited information provision can meet certain objectives, such as extension of battery lifetime, which may not be met if only UE location information and its capabilities information are considered.

The RP enables the PDP to have dynamic control over the enhanced ANDSF behaviour. The PDP can signal control decisions for improving provision of enhanced ANDSF information to the UEs and for supporting certain functions.

The functions include establishing and terminating of RP session, provisioning, updating, and removing of information provisioning rules between the PDP and the enhanced ANDSF, which includes requesting for Information Control from enhanced ANDSF to PDP in a pull mode, and provisioning of Information Control from the PDP to the enhanced ANDSF in a push mode, transmitting of UE-related events from the enhanced ANDSF to the PDP, and - subscribing to UE-related events from the PDP to the enhanced ANDSF.

The enhanced ANDSF has been extended to incorporate information received via the RP for deciding which data for sending the UE is to be limited or to be selected. The decision can be based on control information or provisioning information that the enhanced ANDSF receives via the RP. The control information can be requested by the enhanced ANDSF in a pull mode, or the enhanced ANDSF may receive the control informa- tion in an unsolicited manner by a push mode. In a generic sense, the enhanced ANDSF may also receive the control information from various PDPs that hosts various information providing network functions or network monitors, rather than one PDP. The enhanced ANDSF is able to evaluate the received in- formation. The enhanced ANDSF may also have certain mechanisms to resolve conflicts in the event of need. Thus, the PDP is able to provide Information Control besides just Policy Control and Charging Control. The Policy Control includes Gate Control.

Advantageously, the application is applicable to any networking equipment, such as the UE, that uses ANDSF functionality for interconnecting between different access communication networks. A better coverage and lower operating expenditures can be expected because of an improved traffic via radio interface that leads to a higher online time and a higher data transfer rate for its subscribers. An efficiency of network operation is increased because its subscribers can have im- proved connection to available resources using scanning methods that can be implemented in UE devices for appropriate radio interfaces. Customer loyalty can be increased because network connection to different access technologies with one home operator is possible.

In short, the application provides a reference point or an interface between the enhanced ANDSF and certain external entity, such as a PDP or PCRF, that hosting an information pro- viding functionality to enable the enhanced ANDSF to cope with dynamisms inherent in mobile telecommunication networks. The application also provides schemes for exchanging information between the enhanced ANDSF and the external entity, extension of the enhanced ANDSF, extension of Diameter protocol for a 3GPP network deployment, and a procedure for the 3GPP network deployment.

Fig. 1 illustrates architecture of Access Network Discovery Support Function (ANDSF) ,

Fig. 2 illustrates handover scheme between a 3GPP network access and a trusted or un-trusted non-3GPP network access with the ANDSF of Fig. 1,

Fig. 3 illustrates a non-roaming architecture for an EPS (Evolved Packet System) network,

Fig. 4 illustrates an extension of the architecture of

Fig. 1 for an improved ANDSF information provision- ing,

Fig. 5 illustrates 3GPP network deployment of Fig. 3 with an improvement,

Fig. 6 illustrates a non-roaming architecture of Fig. 3 with an improvement, Fig. 7 illustrates a MSC (Message Sequence Chart) of the improved non-roaming architecture of Fig. 6 for an improved provision of ANDSF information in a pull mode,

Fig. 8 illustrates a MSC of the extended non-roaming architecture of Fig. 6 for improved provision of ANDSF information in a push mode,

Fig. 9 illustrates a baseline scenario of a 3GPP network access that is related network service SbH,

Fig. 10 illustrates a MSC of the baseline scenario of Fig.

9,

Fig. 11 illustrates an extended AVP (Attribute Value Pair) table,

Fig. 12 illustrates an AVP format of an Information Control AVP of Fig. 11, and

Fig. 13 illustrates an AVP format of the Information- Control-Report AVP of Fig. 11.

Figs. 1 to 13 have similar parts. The similar parts have similar names or same reference numbers. The description of the similar parts is thus incorporated by reference.

Fig. 1 shows architecture 10 of Access Network Discovery Sup- port Function (ANDSF) . The architecture 10 includes a UE (User Equipment) 11 that is connected to an ANDSF network element 12 of an EPS (Evolved Packet System) network via S14 reference point (RP) 13 and multiple heterogeneous network accesses 14 of communication networks. The ANDSF network ele- ment 12 is also referred as ANDSF 12 for simplicity. The heterogeneous network accesses 14 comprise 3GPP (Third Generation Partnership Project) IP (Internet Protocol) Accesses and Trusted or Un-trusted Non-3GPP IP Accesses.

ANDSF INFORMATION PROVISIONING

Schemes or guidelines for multi-access network selection and discovery when 3GPP network access and non-3GPP network access are available or when multiple non-3GPP network accesses are available are provided by Section 4.8 of 3GPP specification, 3GPP (Third Generation Partnership Project) TS 23.402 V8.3.0 (2008-09), "Architecture enhancements for non-3GPP accesses", Release 8, http://www.3gpp.org/ftp/ Specs/html- info/23402. htm. The multi-access network selection is pro- vided for multiple access network operators and for multiple RAT (Radio Access Type) types. The discovery is referred to as Network Discovery and Selection (NWDS) .

The schemes, as provide here, includes - the EPS network that may provide the UE 11 with assistance data and/or network policies about available network accesses to allow the UE 11 to scan for the network accesses and to select the network access, the UE 11 may provide information to the communication network for retrieving of the assistance data and/or the network policies information, the EPS network allows a home and a visited network operator to influence the network access in which the UE 11 handovers to when it is in active mode or re-selects when it is in idle mode, and the multi-access NWDS is used for single-radio terminal and multiple-radio terminals.

A handover can switch communication that includes one, more or all active sessions between available network accesses in which a 3GPP network access is switched to a non-3GPP network access, vice versa, or one non-3GPP network access is switched to another non-3GPP network access. The ANDSF 12 limits amount of information provided to the UE 11 based on information, such as current location information of the UE, capabilities information of the UE 11, and opera- tor network policy information as described in section

4.8.2.1 of 3GPP (Third Generation Partnership Project) TS 23.402 V8.3.0 (2008-09), "Architecture enhancements for non- 3GPP accesses", Release 8, http://www.3gpp.org/ftp/Specs/ html-info/23402.htm.

The UE 11 can direct queries the ANDSF 12 via the S14 reference point using a pull mode, wherein the ANDSF provides information to the UE 11 only upon receipt of the queries from the UE 12. It enables dynamic provision of information to the UE for NWDS procedures.

A push mode and/or combination of pull-push mode may be supported as well, as shown in 3GPP (Third Generation Partnership Project) TS 23.402 V8.3.0 (2008-09), "Architecture en- hancements for non-3GPP accesses", Release 8, http : //www.3gpp . org/ftp/Specs /html-info/23402.htm, section 4.8.3.

In the pull mode, the ANDSF 12 provides information to the UE 11 without the UE 11 requesting or soliciting for the information .

According to section 4.8.2.1 of 3GPP (Third Generation Partnership Project) TS 23.402 V8.3.0 (2008-09), "Architecture enhancements for non-3GPP accesses", Release 8, http://www.3gpp.org/ftp/Specs/ html-info/23402.htm, and depending on location area, the ANDSF provides the information relating to

- inter-system mobility policy, which identifies when mobility is allowed or is restricted, depending on validity conditions that may include time duration, and location area, and access network discovery information. This information can comprise a list of access networks available in the vicinity of the UE for all the access technology types, such as WLAN and WiMAX technology types, as requested by the UE if applicable, access network identifier, such as SSID (service set identifier) of a WLAN, or other technology specific information, like one or more carrier frequencies information. The technology specific information also depends on validity conditions that may in- elude time duration and location area.

Hence, the ANDSF 12 limits the amount of information, that is improves ANDSF information provisioning to UE 11,

Fig. 2 shows a handover scheme 18 between a 3GPP network Access and a trusted or an un-trusted non-3GPP IP network Access with the ANDSF of Fig. 1.

The handover scheme 18 includes a step 21 of the UE 11 con- necting with the EPC over the 3GPP or the non-3GPP network access, as shown in Fig. 2. This is followed by the step 22 of discovering the ANDSF 12 by the UE 11.

After this, the UE 11 performs the step 23 of requesting for access network information. UE location information, like cell identity or other location data, may be included in message Access Network Info Request. If the UE location is not included then other mechanisms may be used by the ANDSF 12 to identify the UE current location.

The ANDSF 12 then response with the access network information via step 24. The UE 11 later makes access network selection and handover decision in step 25. Afterward, the UE 11 initiates inter-system handover in step 26.

EPS ARCHITECTURE Fig. 3 depicts a non-roaming Architecture 30 for an EPS (Evolved Packet System) network.

A non-roaming architecture for the EPS network is described in section 4.2.2 of 3GPP (Third Generation Partnership Project) TS 23.402 V8.3.0 (2008-09), "Architecture enhancements for non-3GPP accesses", Release 8, http://www.3gpp.org/ftp /Specs/html-info/23402.htm.

The EPS network has Gx interfaces, Gxa 31, Gxb 32, and Gxc 33 as shown in Fig. 3. The Gxa interface 31 is used when the Trusted non-3GPP Access network is owned by the same network operator, whilst the Gxc 33 interface is used only in the case of PMIP (Proxy Mobile IP) variant of S5 interface or S8 interface.

SERVICE BASED HANDOVER (SbH)

A Service based Handover (SbH) functionality relies on de- scription of Monamiβ (Mobile Nodes and Multiple Interfaces in IPv6) WG (Working Group) of the IETF for IP flow management mechanisms .

The flow management mechanisms are described in H. Soliman, N. Montavont, N. Fikouras, and K. Kuladinithi, "Flow Bindings in Mobile IPv6 and Nemo Basic Support", draft-soliman- monami6-flow-binding-04.txt, February 2007, http ://tools.ietf. org/id/draft-soliman-monami6-flow-binding- 04. txt .

Monami6 related mechanisms refer to Mobile IPv6 based environments wherein a Mobile Node (MN) informs a Home Agent (HA) about information related to the IP flows.

The Mobile IPv6 is shown in D. Johnson, C. Perkins, and J. Arkko, "Mobility support in IPv6", RFC3775, IETF (Internet Engineering Task Force), June 2004, http://www.faqs.org/rfcs /rfc3775.html. The MN is also called a UE (User Equipment) .

The information is used by the HA to identify IP flows and to distribute the IP flows to relevant network interfaces of the MN that are available. In this manner, multiple network interfaces of the MN are used.

A Monamiβ WG (Work Group) focuses on producing specifications that allows simultaneous use of multiple IPv6 addresses for mobile hosts or for routers. These multiple addresses could be assigned to a single or to multiple interfaces. In this way, the IP flows can be directed to different interfaces.

The specification also provides flow bindings, which are mechanisms to bind a certain IP flow to one care-of-address of the MN. Mobile IPv6 allows binding of all traffic to a single interface. This specification achieves a finer granularity of flow binding on interfaces for steering the flows. A rule identification option is included in Binding Updates (BU) and Binding Acknowledgements (BA) for binding flows to care-of- address, and consequently to the interface.

A flow is shown in S. Deering, R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", RFC 2460, IETF, http://tools.ietf.org/html/rfc2460.

It is possible to add or to remove a flow from a certain care-of-address. This functionality is used for flow management actions like splitting, weighting, or dropping a traffic of the MN that is received from the HA, a Correspondent Node (CN) , or a Mobility Anchor Point (MAP) .

The relevant information are also provide by

R. Wakikawa, T. Ernst, K. Nagami, V. Devarapalli, " Multiple Care-of Addresses Registration", draft-ietf- monami6-multiplecoa-02. tx, 5 March 2007, http://tools.ietf. org/html/draft-ietf-monami6- multiplecoa-02,

H. Soliman, N. Montavont, N. Fikouras, K. Kuladinithi, "Flow Bindings in Mobile IPv6 and Nemo Basic Support", February 2007, draft-soliman-monami6-flow-binding- 04.txt, http://tools.ietf. org/html/draft-soliman- monami 6-flow-binding- 04 ,

- T. Kauppinen, H. Mahkonen, M. Kuparinen, C. Larsson, H. Levkowetz, "Filter Interface Identifier Binding in Mobile IPv6", October 16, 2006, draft-kauppinen-monami6- binding-filter-rule-00. txt, http://tools.ietf. org/html/draft-kauppinen-monami 6- binding-filter-rule-00, and

C. Larsson, H. Levkowetz, H. Mahkonen, T. Kauppinen, "A Filter Rule Mechanism for Multi-access Mobile IPv6", October 23, 2006, draft-larsson-monami6-filter-rules-01, http://tools.ietf. org/html/draft-larsson-monami6-filter- rules-01.

Fig. 4 shows the architecture of Fig. 1 with an extension for improving ANDSF information provisioning.

Fig. 4 has an extended architecture 35 that includes a UE (User Equipment) 38 that is connected to an enhanced ANDSF network element 39 of an EPS (Evolved Packet System) network via S14 reference point (RP) 40. The enhanced ANDSF network element 39 is also referred as enhanced ANDSF 39 or an extended ANDSF 39.

The extended architecture 35 also comprises multiple heterogeneous network accesses 42 of communication networks. The PDP 44 is a host for a network functionality that can be called Service based Handover (SbH) . The enhanced ANDSF 39 is connected to a PDP (Policy Decision Point) 44 via a S15 RP 45.

The SbH steers traffic to multiple simultaneously available network's and mobile device's interfaces using an IETF flow management mechanism.

The flow management mechanism is shown in H. Soliman, N. Mon- tavont, N. Fikouras, and K. Kuladinithi, "Flow Bindings in Mobile IPv6 and Nemo Basic Support", draft-soliman-monami6- flow-binding-04.txt, February, 2007, http://tools.ietf.org/ id/draft-soliman-monami6-flow-binding-04. txt

A decision engine of the SbH that is hosted in the PDP 44 can steer individual traffic flows via different network accesses, which are available in a location of the UE 38.

Due certain constraints, such as user subscription, maintenance, or network conditions, the SbH can use only certain network accesses, like WLAN network access and GERAN (GSM

EDGE Radio Access Network) network access out of all available accesses. Consequently, the UE 38 does not need to be informed over other network accesses, like WiMAX network access or LTE network access. The enhanced ANDSF 39 improve its information provisioning by providing appropriate rather than all information to the UE 38 by the S15 interface 45 using an information element called Information Control that uses external decisions that are made by the SbH. This is unlike most other ANDSF implementation that provides all the avail- able network accesses even though certain functionality deployed in the network may use only a few of the network access .

The S15 RP 45, as provided here, corresponds to a Gxd inter- face whilst the PDP 44 corresponds to PCRF (Policy Control and Charging Rules Function) in a 3GPP network deployment. Thus, the S15 RP 45 enables the PDP 44 to have dynamic control over ANDSF behavior.

Fig. 5 shows 3GPP network deployment of the extended archi- tecture 35 of Fig. 4. Fig. 5 depicts a heterogeneous network environment 50 that has multiple access networks with similar or different network access technologies that are connected an EPC (Evolved Packet Core) network 52.

The multiple access networks includes a LTE (Long Term Evolution) -SAE (System Architecture Evolution) access network 53, a 2.5/ 3G (Generation) access network 54, a WLAN (Wireless Local Area Network) 3GPP IP access network 55, and a WiMAX (Worldwide Interoperability for Microwave Access) access net- work 56.

Multiple UEs (User Equipments) 58 are connected to the multiple access networks. The UEs 58 have SbH (Service based Handover) clients 60 and ANDSF clients 61.

The EPC network 52 has an ANDSF Server 57 and a PCRF (Policy Control and Charging Rules Function) 62 that acts as a PDP (Policy Decision Point) . The PCRF 58 hosts a SbH Agent 59. The ANDSF Server 57 is also called an ANDSF.

The enhanced ANDSF 39 of the EPC network 52 supports access network discovery and mobility between 3GPP network access and non-3GPP network access, even though a 3GPP network access can be different from a non-3GPP network access like a LTE-SAE network access can be different from a WiMAX network access .

The EPC network 52 is a form a core network.

Fig. 6 shows the non-roaming architecture of Fig. 3 with an improvement. Fig. 6 has an improved non-roaming architecture 70 that is part of an EPS and is deployed as a 3GPP network. The improved non-roaming architecture 70 has an extended PCRF 71 that is connected to an extended ANDSF 72 by a Gxd interface 73. A UE 74 is connected to the extended ANDSF 72. Support of the Gxd interface 73 for a pull mode and a push mode as well as related Message Sequence Charts (MSCs) of the extended non-roaming architecture 70 are shown in Fig. 7 and in Fig. 8. Appropriate Diameter protocol extensions are also provided, although this does not exclude other implementations .

The extended PCRF 71 is extended by certain network function and it can include a Service Based Handover (SbH) function or service, which is able to provide information, via the interface Gxd 73, to the extended ANDSF 72 for improving the ex- tended ANDSF 72.

EXTENDED CONTROL PROCEDURES IN A 3GPP DEPLOYMENT OVER Gxd INTERFACE - INFORMATION CONTROL IN A PULL MODE

ANDSF -> PCRF

The extended ANDSF 72 can send a CCR (Credit Control Request) message with a CC-Request-Type AVP (Attribute Value Pair) set to a "UPDATE_REQUEST" value.

The CCR message is described in H. Hakala, L. Mattila, J-P. Koskinen, M. Stura, J. Loughney, "Diameter Credit-Control Application", August 2005, RFC 4006, http://tools.ietf.org/ html/rfc4006.

The extended ANDSF 72 can provide an Information Control request with an extended Event-Trigger AVP, which is the specific event that caused such request, and an Information- Control-Report AVP, which includes processed or any previ- ously provisioned Information Control.

PCRF -> ANDSF The extended PCRF 71 can provide an Information Control answer that includes an improved Information-Control AVP, which includes the Information Control information according an outcome of an internal PCRF decision making function. The in- ternal PCRF decision making function can be related to a SbH (Service Based Handover) service. One SbH service is provided for all IP (Internet Protocol) flows of an active communication session.

If the extended PCRF 71 is not able to provide an Information Control response to a request for the Information Control by the extended ANDSF 72, the extended PCRF 71 may reject the Information Control request using a Diameter CCA (Credit Control Answer) command with certain resultant error code. The Diameter is a networking protocol for purpose of AAA (Authentication, Authorization, and Accounting) . The inability of the extended PCRF 71 to provide the Information Control information can be due to incomplete, erroneous, or missing information, such as unavailability of subscription related in- formation.

If the extended ANDSF 72 receives the CCA command with the resultant error code, the extended ANDSF 72 may reject an Access Network Info Request that initiated the CCR message.

Corresponding description of the MSCs of the extended non- roaming architecture 70 are provided below.

Fig. 7 depicts a MSC (Message Sequence Chart) 78 of the im- proved non-roaming architecture of Fig. 6 for improving provision of ANDSF information in a pull mode.

The MSC 78 includes a step 80 of connecting with the extended non-roaming architecture 70 of the EPS by the UE 74, as de- picted in Fig 7. The UE 74 then discovers or locates the extended ANDSF 72, in a step 81. The UE 74 later sends an Access Network Information Request to the extended ANDSF 72, in a step 82. Afterwards, the extended ANDSF 72 discovers or locates the extended PCRF 71, in a step 83. The step 83 is described in section 7.6 of 3GPP TS 23.203 V8.2.0 (2008-06), "Policy and charging control architecture", Release 8, http://www.3gpp. org/ftp/Specs /html-info/23203. htm.

The extended ANDSF 72 then sends an Information Control request of a DIAMETER CCR command to the extended PCRF 71, in a step 84. The Information Control request contains an event trigger and a report about the Information Control using the Information Control request. The event trigger is a specific event that generates the Information Control request. The Information Control includes processed or any previously provi- sioned Information Control.

Afterwards, an internal decision making function of the extended PCRF 71 performs decision-making and it selects control information for the extended ANDSF 72 to enable it to improve its information provisioning to the UE 74, in a step 85. The control information can comprise information that is available to the extended PCRF 71 but not available to the extended ANDSF 72. The control information can also include decision information or an objective function with constraint criteria, such as traffic flow information to help the UE 74 focuses on certain network accesses.

Then, the extended PCRF 71 provides an Information Control answer of a Diameter CCA command to the extended ANDSF 72, in a step 86. The Information Control answer includes an Information Control that is relevant for the extended ANDSF 72 to decide on its information provisioning to the UE 74. The Information Control is an outcome of a PCRF internal decision making function. The PCRF internal decision making function can use information that is provided by the SbH function.

The extended ANDSF 72 later makes decision for providing information to the UE 74 using the additional control informa- tion, in addition to UE location information or capabilities information as well as certain network operator policies, in a step 87. The additional information improves the information provision decision-making process. Hence, the extended ANDSF 72 is able to limit further the information sent to the UE 74, as needed.

If the additional control information about used network interfaces by SbH control logic via the extended PCRF 71, is provided, the extended ANDSF 72 may focus its information provisioning to the UE 74 to these dedicated access networks, whilst dropping any information for other network accesses.

The UE 74 later makes access network selection and HO (hand- over) decision using the additional control information, in a step 89. Then, the UE 74 initiates an inter-system HO, in a step 90. One SbH service is provided for all IP (Internet Protocol) flows of an active communication session.

EXTENDED CONTROL PROCEDURES IN A 3GPP DEPLOYMENT OVER Gxd INTERFACE - INFORMATION CONTROL IN A PUSH MODE

PCRF -> ANDSF

The extended PCRF 71 may decide to provide the Information Control without obtaining a request from the extended ANDSF 72, for example in response to outcome of a SbH decision- making functionality of a related PDP that is hosted by the extended PCRF 71.

The extended PCRF 71 can send a Diameter RAR (Re-Auth- Request) message for requesting the Information Control that contains within an Information Control request an improved Information-Control AVP, which includes the Information Con- trol according an outcome of PCRF internal decision making. The internal decision-making may be related to SbH functionality. ANDSF -> PCRF

The extended ANDSF 72 can reply with a Diameter RAA message that contains within a Information Control answer an improved Information-Control-Report AVP, which includes processed or any previously provisioned Information Control and their status of requested improvement.

If a corresponding improvement of the information provision- ing cannot be established, then the extended ANDSF 72 can reject the activation of the Information Control using a Diameter RAA (Re-Auth-Answer) command with certain error result code. If the extended PCRF 71 receives a RAA command with this code, the extended PCRF 71 may re-evaluate the informa- tion provisioning decision that initiated the RAR command.

Fig. 8 depicts a MSC (message sequence chart) 95 of the extended non-roaming architecture 70 of Fig. 6 for improving ANDSF information provisioning in a push mode. The push mode is initiated by the extended PCRF 71.

The MSC 95 commences with the UE 74 connecting with the extended non-roaming architecture 70 of the EPS, in a step 97, as shown in Fig. 8.

The extended PCRF 71 then makes information provisioning decision, in a step 98. The information provisioning decision comprises a step of selecting control information for the extended ANDSF 72 to enable it to improve its information pro- visioning to the UE 74. The control information can comprise information that is available to the extended PCRF 71 but not available to the extended ANDSF 72. The control information can also include decision information or objective function with constraint criteria, such as traffic flow information to help the UE 74 focuses on certain network access.

Then, the extended PCRF 71 performs a step 99 of discovering or locating the extended ANDSF 72. This step is described in section 4.8.4 of 3GPP (Third Generation Partnership Project) TS 23.402 V8.3.0 (2008-09), "Architecture enhancements for non-3GPP accesses", Release 8, http://www.3gpp.org/ftp/Specs/ html-info/23402.htm.

The extended PCRF 71 then sends a Diameter RAR command for the Information Control request that contains the Information Control to the ANDSF 72, in a step 100. The Information Control is provided by an outcome of an internal decision making function of the PCRF 71. The internal decision making function can be influenced by the SbH function.

Later, the extended ANDSF 72 makes decision on information provision to the UE 74, in a step 101. The extended ANDSF 72 has additional control information, in addition to UE location information or capabilities information as well as certain network operator policies, to improve its decision- making. The additional information can be used to limit further information that is intended for providing to the UE 74.

Where SbH additional information about used network interfaces by SbH control logic is provided, the extended ANDSF 72 may focus its information provisioning to the UE 74 to these dedicated access networks that are notified by the extended PCRF 71, whilst leaves out any information for other network accesses .

Depending on the step 101, the extended ANDSF 72 afterward can provide an Access Network information request to the UE 74, in a step 101.

Using a Diameter RAA command, the extended ANDSF 72 informs the extended PCRF 71 via an Information Control answer about an event trigger and a report about Information Control, which includes processed or any previously provisioned Information Control and their status of requested improvement, in a step 102. The extended ANDSF 72 can inform the extended PCRF 71 via an SBH service of the PCRF 71. The UE 74 then makes an access network selection and a Handover decision using the given information, in a step 103. Afterward, the UE 74 provides an Access Network Info Answer to the extended ANDSF 72, in a step 104. The UE 74 then initiates the inter-system Handover, in a step 105.

In the case of the SbH service, the handover is done on a per IP flow basis.

EXTENDED CONTROL PROCEDURES IN A 3GPP DEPLOYMENT OVER Gxd INTERFACE - APPLICATION FOR EXTENDED PCRF (WITH SERVICE BASED HANDOVER FUNCTIONALITY)

Fig. 9 shows a baseline scenario 110 or an environment of

3GPP network access 112 that is related to the network service SbH. The environment 110 provides for a better understanding of a MSC (message chart sequence) of Fig. 10. The 3GPP network access 112 has a UMTS network access.

Location point 1 :

At location point 1 of Fig. 9, a user Bob is walking around in a conference area of an airport with various network ac- cesses that are available in parallel. During former or initial SbH-related actions, its UE gets its services simultaneously, via a UMTS network access 112 and a WLAN network access 113 of a first SSID (Service Set Identifier) , for two distinct traffic flows. The UE obtains a voice traffic flow via the UMTS network access 112 and a video traffic flow via the first SSID WLAN network access 113.

From an ANDSF perspective, information provided to the UE here depends solely from its location. As described here, the provided information is for the UMTS network access 112 and for the first SSID WLAN network access 113, since only both network accesses are available to the UE location at the location point 1. Location point 2 :

Bob, while walking, enters additional coverage areas of a WLAN network access 114 of a second SSID and of a WiMAX network access 115 at a location point 2 of Fig. 9. A network service, which may not need user interaction, decides in the background to re-direct the video traffic flow to the second SSID WLAN network access 114, while leaving the voice traffic flow to be transmitted via the UMTS network access 112.

The embodiment also illustrates switching of communication. In this case, the video traffic flow is switched from the first SSID WLAN network access 113 to the second SSID WLAN network access 114. Moreover, certain active session or sessions are switched, rather that all active sessions. The voice traffic flow is not switched and continues to access the UMTS network access 112.

From the ANDSF perspective, two phases can be distinguished.

In the initial phase, information provided to the UE depends solely from its location. As shown here, the provided information through the UMTS network access 112, the WLAN network access 113 of the first SSID, the WLAN network access 114 of the second SSID, and the WiMAX network access 115 are available in parallel at the location point 2. A potential additional information providing network service, like SbH, has not yet provides information to an ANDSF of the UE. This may be to due to internal processing time.

The initial phase ends when the decision making of mentioned network service SbH provides additional information to the ANDSF. The ANDSF then improves its information provisioning to the UE. The additional information, as provided here, is about used network interfaces. The UE 58 has multiple radio interfaces that allow it to communicate with the WLAN access networks 113 and 114, the WiMAX access network 115, and the 3GPP access network 112.

Fig. 10 shows a MSC 120 of the baseline scenario 110 of Fig. 9 that uses a network service SbH. Parts of the MSC 120 are also shown on the 3GPP network deployment of Fig. 5. These parts have the same part numbers. The description of these parts are included by reference. Roles of an ANDSF Server and an ANDSF Client of the UE 58 are not explicitly mentioned below for easier readability.

The MSC 120 shows a method of improving ANDSF information provisioning to the UE 58 that has multiple radio terminals. The multiple radio terminals that allow the UE 58 to communicate with the WLAN access networks 113 and 114, the WiMAX access network 115, and the 3GPP access network 112.

At the location point 1 of Fig. 9, the UE 58 connects with the EPC via the UMTS access network 112 of a 3GPP network and the first SSID WLAN access network of SSIDl of a non-3GPP network access, in a step 121 that is shown in Fig. 10.

The UE 58 then moves to the location point 2 of Fig. 9 and it enters or accesses additional network access systems, as shown in a step 122 of Fig. 10. The additional network access systems comprise the second SSID WLAN network access 114 and the WiMAX network access 115. After ANDSF discovery, a ANDSF Client of the UE 58 is internally triggered and it requests information for the network accesses within a current area of the UE 58 by sending Access Network Info request together with the UE current location information to the ANDSF 57. In parallel, the SbH Client 60 of the UE 58 is also internally triggered and it starts communication with the SbH Agent 59 to decide on traffic flow steering. This is not shown in the Fig. 10. The ANDSF discovery is shown Figure 8.5.1-1, step 2 of 3GPP (Third Generation Partnership Project) TS 23.402 V8.3.0 (2008-09), "Architecture enhancements for non-3GPP accesses", Release 8, http://www.3gpp.org/ftp/Specs/html-info/23402.htm.

An Access Network Info request is then sent from the UE 58 to the ANDSF 57, in a step 123. The step 123 is also described in Figure 8.5.1-1, step 3 of 3GPP (Third Generation Partnership Project) TS 23.402 V8.3.0 (2008-09), "Architecture en- hancements for non-3GPP accesses", Release 8, http : //www.3gpp . org/ftp/Specs /html-info/23402.htm.

The ANDSF 57 later performs PCRF discovery, in a step 124. The step 124 is also described in section 7.6 of 3GPP TS 23.203 V8.2.0 (2008-06), "Policy and charging control architecture", Release 8, http://www.3gpp.org/ftp/Specs/html- info/23203.htm

Then, the ANDSF 57 provides a Diameter CCR command with an Information Control request to the related PCRF 62, in a step 125. The Information Control request contains an event trigger that, for this case, comprises changed location of the UE, and a report about the a Information Control, which includes processed information that comprised current active Information Control of the first and the second SSID WLANs access networks 113 and 114, the WiMAX access network 115, and the UMTS access network 112.

From the ANDSF perspective, at this step the ANDSF 57 is ask- ing the SbH Agent 59 of the PCRF 62 whether it has additional information to improve provision of its information to the UE 58. The SbH Agent 59 of the PCRF 62, as provided here, is acting as a PDP (Policy Decision Point) .

The SbH Agent 59 of the PCRF 62 later performs an information provisioning decision step, in a step 126. In this case, the SbH Agent 59 has not yet finalized the decision and consequently, the SbH Agent 59 has no additional information. Hen- ce, the SbH Agent 59 replies after successful authorization via Subscriber Profile Repository (SPR) from PCC (Policy and Charging Control) architecture with no change of Information Control information in an Information Control answer. The PCC architecture is shown in 3GPP TS 23.203 V8.2.0 (2008-06), "Policy and charging control architecture", Release 8, http://www.3gpp.org/ ftp/Specs/html-info/23203.htm. From the ANDSF perspective, in this step the ANDSF 57 is awaiting for an answer message.

If the above Information Control information were available at this step, then following steps 127 to 132 are bypassed or are not performed.

Afterwards, the SbH Agent 59 of the PCRF 62 sends a Diameter CCA command with an Information Control answer to the ANDSF 57, in a step 127. The Information Control answer has the same Information Control information as the received Information Control information of the step 125. The Control infor- mation is intended to allow the ANDSF 57 to decide regarding the information provisioning to the UE 58.

Using available information, the ANDSF 57 then decides to send an Access Network Info Response message to the UE 58, in a step 128. The Access Network Info Response message includes information regarding the first and the second SSID WLANs network accesses 113 and 114, the WiMAX network access 115, and the UMTS network access 112. At this point, the ANDSF 57 has no additional information besides the UE location infor- mation or the capabilities information as well as the certain network operator policies to improve its decision-making in relation to its information provisioning to the UE 58.

The Access Network Info Response message is later sent from the ANDSF 57 to the UE 58, in a step 129.

SbH-related communication between the SbH Agent 59 and the SbH Client 60 results in a SbH decision regarding IP traffic flow steering. It is assumed that the UE 58 controls SbH mechanisms. The SbH Client 60 of the UE 58 then triggers access network selection for related IP traffic flows, as shown in a step 130.

The SbH Client 60 may also decide on UE connection using on other information or other sources. For example, the decision of the UE connection to the UMTS access network 112 and the second SSID WLAN access network 114 can be based on access network signal strength.

The UE 58 afterwards initiates an inter-system handover from the first SSID WLAN 113 to the second SSID WLAN 114, in a step 131. Communication between the UE 58 and the network, that is communication between the SbH Client 60 and the SbH Agent 59, steers relevant traffic flows from the first SSID WLAN 113 to the second SSID WLAN 114 in accordance to the SbH decision made by the SbH Client 60 of the UE 58. In parallel, other traffic-flows continue to use the UMTS network access 112.

The SbH Agent 59 that is a function of the PCRF 62 and the SbH Client 60 that is hosted by the UE 58 provides the Service Based Handover (SbH) .

The SbH Agent 59 of the PCRF 62 later has additional information for the ANDSF 57 based on its SbH decision, in a step 132. Hence, the PCRF 62 sends a Diameter RAR command with the Information Control request that contains the Information Control. As provided here, a Priority-Identifier AVP of TWO is assigned to the UMTS network access 112 and the second SSID WLAN network access 114. The Priority-Identifier AVP of TWO is highest priority that is used by SbH. A Priority- Identifier AVP of ONE is assigned to the first SSID WLAN net- work access 113. This assignment can be because the first

SSID WLAN network access 113 is already an authorized network access and the UE 58 is preparing to access it. A Priority- Identifier AVP of ZERO is assigned for the WiMAX network access 115.

From the ANDSF perspective, the ANDSF 57 at this point does not know of the SbH decision, and of course does not know about any potential consequences of the SbH decision.

A RAR (Information Control request) command including the modified Information Control is then sent from the SbH Agent 59 of the PCRF 62 to the ANDSF 57, in a step 133.

The ANDSF 57 then has the additional information besides UE location information or capabilities information to improve its decision making related to its information provisioning to the UE 58. Hence, the ANDSF 57 may further limit information sent to the UE 58 by discarding any information for the WiMAX network access 115. The ANDSF 57 can decide on what to provide and what not to provide, in a step 134. This improvement step, as provided here, relates to discarding WiMAX re- lated information in the ANDSF 57, which is not possible without the implementation as provided in this embodiment.

Later, the ANDSF 57 sends Access Network Info Request message to the UE 58, in a step 135.

With a Diameter RAA command, the ANDSF 57 informs the SbH Agent 59 of the PCRF 62, in a step 136. The Diameter RAA command contains an Information Control answer about an event trigger, which is the specific event that caused the said an- swer. In this case, the Information Control answer contains the location change of the UE, a report about Information Control, which is processed and is updated in the step 134, Information Control that is with identical received information control of step 133, and the status indication of a suc- cessful improvement.

However, the ANDSF decision may also consider other information providing sources or factors. As an example, the ANDSF 57 may leave the WiMAX network access with Priority- Identifier AVP set to ONE because other network functions may need that interface.

The UE 58 makes access network scanning decision, in a step 137. The UE 58 has the access network information to improve its scanning for network accesses. In this case, the UE 58 stops scanning for WiMAX network access. Hence, battery lifetime of the UE 58 is improved. This improvement is not possi- ble without the implementation as provided in this embodiment .

Afterward, the UE 58 sends an Access Network Info answer to the ANDSF 57, in a step 138.

Considering the above-mentioned MSC, other message sequence that finally intends to reach the same improvement results are also possible and are not excluded with this embodiment.

SPECIFICATION OF DIAMETER EXTENSIONS

Appropriate extensions to Diameter AVPs are provided below. Since the information provided by the PCRF depends on control logic, with the SbH service as one example, only attribute names and their applicability are provided below.

Fig. 11 shows an extended AVP (Attribute Value Pair) table 140 for Gx RP. The table 140 shows a column 142 of attribute names, a column 143 of AVP codes, a column 144 of Access (Ace.) type, and a column 145 of applicability.

Although the table 140 provides several values of AVP codes for the respective attribute names, other values are also possible. The AVPs that have an "IC" code are applicable to information control provided by the ANDSF, as shown in Fig. 11. The AVPs that have an "ALL" code are applicable to all charging control, network policy control, and information control . The column 143 of AVP codes includes an Event-Trigger AVP 150, an Information-Control AVP 151, an Information-Control- Report AVP 152, a carrier-Frequency AVP 153, and a priority- identifier AVP 154.

o Extended Event-Trigger AVP for all access types

The Event-Trigger AVP 150, which has an AVP code of 1006, is a value type Enumerated. When it is sent from a PCRF to an

ANDSF, the Event-Trigger AVP 150 indicates an event that causes a re-request of information control whereas when it is sent from the ANDSF to the PCRF, the Event-Trigger AVP 150 indicates that the corresponding event has occurred at a ga- teway.

The following value is added:

UE_LOCATION_CHANGE An UE_LOCATION_CHANGE value is used in a CCA command and in a RAR command by the PCRF to indicate that upon a change of the UE location, the Information Control is requested. When it is used in a CCR command, the UE_LOCATION_CHANGE value indicates that an ANDSF gener- ates the request because the location changed.

Other triggers or uses of the UE_LOCATION_CHANGE value that depends on network functions are also possible.

o Improved Information-Control AVP for all access types

The Information-Control AVP 151 of AVP code 1030 may be of value type of GROUPED and it includes at least information about access network and dedicated network interfaces. It can include a network function SbH that is hosted by a PCRF. It has to be applicable for all types of network accesses. o Improved Information-Control-Report AVP for all access types

The Information-Control-Report AVP 152 of AVP code 1031 is of types GROUPED, and it is used to report any previously provisioned Information Control and an optional status of requested improvement.

Fig. 12 shows an AVP format of the Information Control AVP 151 of Fig. 11. The format utilizes existing definitions where possible. The Information Control AVP 151 has an AVP header value of 1030. The AVP format comprises an IP-CAN-Type AVP 160, a RAT-Type AVP 161, a Carrier-Frequency AVP 162, and a Priority-Identifier AVP 163.

The IP-CAN-Type AVP 160 indicates type of Connectivity Access Network. The Connectivity Access Network type includes a 3GPP Access Network type, a DOCSIS (Data Over Cable Service Interface SpecificationO) Access Network type, a xDSL Access Net- work type, a WiMAX Access Network type, or a 3GPP2 Access

Network type. The 3GPP Access Network type and the The 3GPP2 Access Network type are further described by The RAT-Type AVP 161.

The IP-CAN-Type AVP is shown in section 5.3.27 of 3GPP TS

29.212 V8.0.0 (2008-05), "Policy and Charging Control over Gx reference point", Release 8, http://www.3gpp.org/ftp/Specs /html-info/29212.htm.

The RAT-Type AVP 161 has values ranging from 0 to 999 and are used for generic radio access technologies that can apply to different IP-CAN type AVP 160 and are not IP-CAN AVP specific. For example, WLAN (0) shall be used to indicate that the RAT is WLAN.

The RAT-Type AVP 161 is shown in section 5.3.31 of 3GPP TS 29.212 V8.0.0 (2008-05), "Policy and Charging Control over Gx reference point", Release 8, http://www.3gpp.org/ ftp/Specs/html-info/29212.htm.

The Carrier-Frequency AVP 162 of AVP code 1032 is of value type of Unsigned32, and it indicates one or more carrier frequencies as technology specific information.

With this embodiment, other technology specific information, especially newer access technologies are not be excluded.

The Priority-Identifier AVP 163 of AVP code 1033 is of type Enumerated, and it indicates the priority of a network access point .

The priority values includes

Priority ZERO (0)

This value shall be used to indicate that the network access point is not to be used or is not been used.

Priority ONE (1)

This value is used to indicate that the network access point is of lowest priority.

Priority TWO (2)

This value is used to indicate that the network access point is of priority 2.

Fig. 13 shows an AVP format of the Information-Control-Report AVP 152 of Fig. 11. The Information-Control-Report AVP 152 comprises an Information-Control AVP 165 and an IC-Status- Identifier AVP 166. The format utilizes existing definitions where possible.

The IC-Status-Identifier AVP 166 has optional values for status. The status values comprises

OPTIMIZATION SUCCESS (0) A value of the OPTIMIZATION_SUCCESS status is used to indicate that the improvement of information provisioning in ANDSF is successfully implemented.

OPTIM1ZATION_FAILURE (1)

A value of the OPTIM1ZATION_FAILURE status is used to indicate that the improvement of information provisioning in ANDSF is not implemented.

In the case of OPTIMIZATJON_FAILURE value indication, specify error codes or any other codes for this embodiment is also possible .

With this embodiment, any signaling improvement, for example limitation or reduction of signaling load between network entities, publish & subscribe mechanism between the ANDSF and the PCRF or the SbH service, are also possible.

In short, the embodiment shows a Service based Handover (SbH) function that is implemented in an extended PCRF whilst a Policy Decision Point (PDP) entity resides in the PCRF. It also depicts a S15 RP that corresponds to a Gxd interface that is a variant of a Gx interface for the PCRF of PCC architecture. An extension of Diameter based Gx interface is also provided to support also an Information Control besides Policy Control and Charging Control. The Policy Control includes Gate Control. Message sequence charts (MSCs) from the PCC architecture are also extended to address new Gxd interface.

List of abbreviations

3GPP Third Generation Partnership Project

ANDSF Access Network Discovery and Selection Function

AVP Attribute Value Pair

BA Binding Acknowledgements

BU Binding Updates

CCA Credit Control Answer

CCR Credit Control Request

CN Correspondent Node

CT Core Network and Terminals

EDGE Enhanced Data rates for Global Evolution

EPS Evolved Packet System

EPC Evolved Packet Core

FMC Fixed Mobile Convergence

GERAN GSM EDGE Radio Access Network

GSM Global System for Mobile communications

HA Home Agent

HO Handover

IC Information Control

IETF Internet Engineering Task Force

IP Internet Protocol

LTE Long Term Evolution

MAP Mobility Anchor Point

MSC message sequence charts

MHN Mastering Heterogeneous Networks

MIH Media Independent Handover

MN Mobile Node

MNO Mobile Network Operator mext Mobility Extensions for IPv6

MSC Message Sequence Chart

NAI Network Access Identifier

NO Network Operator

NWDS Network Discovery and Selection

OMA Open Mobile Alliance

PCC Policy and Charging Control

PDP Policy Decision Point 3i

PCRF Policy Control and Charging Rules Function

PEP Policy Enforcement Point

SAE System Architecture Evolution

SAN Serving Access Network

SbH Service based Handover

SSID Service Set Identifier

REST Representational State Transfer

RP Reference Point

RAT Radio Access Type

WG Working Group

WLAN Wireless Local Area Network

WiMAX Worldwide Interoperability for Microwave Access

UE User Equipment

XML Extensible Markup Language

Reference numbers

10 architecture

11 UE (User Equipment) 12 ANDSF network element

13 S14 reference point

14 heterogeneous network accesses 18 handover scheme

21 step 22 step

23 step

24 step

25 step

26 step 30 a non-Roaming Architecture

31 Gxa interface

32 Gxb interface

33 Gxc interface

35 extended architecture 38 UE (User Equipment)

39 enhanced ANDSF network element

40 S14 reference point (RP)

42 heterogeneous network accesses

44 PDP (Policy Decision Point) 45 S15 reference point

50 heterogeneous network environment

52 EPC (Evolved Packet Core) network

53 LTE (Long Term Evolution) -SAE (System Architecture Evolution) access network 54 2.5/ 3G (Generation) access network

55 WLAN (Wireless Local Area Network) 3GPP IP access network

56 WiMAX (Worldwide Interoperability for Microwave Access) access network 57 ANDSF Server

59 SbH Agent

58 UE (User Equipment) 60 SbH (Service based Handover) client

61 ANDSF client

62 PCRF (Policy Control and Charging Rules Func tion)

70 non-roaming architecture

71 PCRF (Policy Control and Charging Rules Func tion)

72 ANDSF

73 Gxd interface

74 UE (User Equipment)

78 MSC (Message Sequence Chart)

80 step

81 step

82 step

83 step

84 step

85 step

86 step

87 step

88 step

89 step

90 step

95 MSC (Message Sequence Chart)

97 step

98 step

99 step

100 step

101 step

102 step

103 step

104 step

105 step

110 baseline scenario

112 3GPP network access

113 first SSID (Service Set Identifier) WLAN net work access

114 second SSID WLAN network access

115 WiMAX network access 120 MSC

121 step

122 step

123 step

124 step

125 step

126 step

127 step

128 step

129 step

130 step

131 step

132 step

133 step

134 step

135 step

136 step

137 step

138 step

140 table

142 attribute names column

143 AVP codes column

144 Access type column

145 applicability column

150 Event-Trigger AVP

151 Information-Control AVP

152 Information-Control-Report AVP

153 carrier-Frequency AVP

154 priority-identifier AVP

160 IP-CAN-Type AVP

161 RAT-Type AVP

162 Carrier-Frequency AVP

163 Priority-Identifier AVP

165 Information-Control AVP

166 IC-Status-Identifier AVP

Claims

1. A network device (39) of a communication network for provisioning access network information to an UE (User Equipment) (38), the network device (39) comprising an interface (45) to receive external information from at least one information provisioning device (44), a calculating device to determine provisioning information for the UE (38) using the received external information, a storage device to store the determined provisioning information.

2. A network device (39) of claim 1 characterised in that the UE (38) comprises at least one radio interface.

3. A network device (39) of claim 1 or 2 characterised in that the received external information comprises network function information.

4. A network device (39) of one of claims 1 to 3 characterised in that the received external information comprises network condition information.

5. A network device (39) of one of claims 1 to 4 characterised in that the information provisioning device (44) comprises an entity for provisioning a PCRF (Policy Control and Charging Rules Function) .

6. A network device (39) of one of claims 1 to 5 characterised in that a calculating device being provided which determines provisioning information for the UE (38) using assis- tance data, network operator policy, function information, and/or network condition information.

7. A communication network that comprises a network device (39) of one of claims 1 to 6.

8. A method for selectively accessing a communication network, the method comprising the steps of receiving external information by a network device - determining information for provisioning to the UE (38) using the received external information, and sending the determined provisioning information to the UE (38) .

9. A method of claim 8 characterised in that the method comprises the further step of requesting for the external information by the network device (39) .

10. A method of claim 8 or 9 characterised in that the method comprises the further step of unsolicited sending the external information to the net- work device (39) .

11. A method of one of claims 8 to 10 characterised in that the method comprises the further step of storing the determined provisioning information for the UE (38) .

12. A method of one of claims 8 to 11 characterised in that the method comprises the further step of evaluating access network information by the UE (38) using the determined provisioning information.

13. A method of one of claims 8 to 12 characterised in that the method comprises the further step of scanning for network accesses by the UE (38) using the determined access network information.

14. A method of one of claims 8 to 13 characterised in that the method comprises the further step of selecting a network for accessing.

15. A method of one of claims 8 to 14 characterised in that the method comprises the further step of accessing the selected network access.