WO2009115015A1 - 网络发现与选择方法、网络***及通信装置 - Google Patents

网络发现与选择方法、网络***及通信装置 Download PDF

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Publication number
WO2009115015A1
WO2009115015A1 PCT/CN2009/070741 CN2009070741W WO2009115015A1 WO 2009115015 A1 WO2009115015 A1 WO 2009115015A1 CN 2009070741 W CN2009070741 W CN 2009070741W WO 2009115015 A1 WO2009115015 A1 WO 2009115015A1
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Prior art keywords
network
andsf
vandsf
handsf
information
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PCT/CN2009/070741
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English (en)
French (fr)
Inventor
于益俊
王珊珊
胡颖
张谦
张进
吴问付
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华为技术有限公司
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Publication of WO2009115015A1 publication Critical patent/WO2009115015A1/zh

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W48/00—Access restriction; Network selection; Access point selection
    • H04W48/18—Selecting a network or a communication service

Definitions

  • Network discovery and selection method network system and communication device
  • the present invention relates to the field of communications technologies, and in particular, to a network discovery and selection method, a network system, and a communication device.
  • EPS evolved packet system
  • LTE Long Term Evolution
  • 3GPP The 3rd Generation Partnership Project
  • An important feature of EPS is the consideration of convergence of multiple access methods, allowing non-3GPP (non-3GPP) networks to access EPS networks.
  • the non-3GPP networks described here include WiMax (Worldwide Interoperability for Microwave Access). In), WLAN (Wireless Local Area Network), CDMA (Code Division Multiple Access), and the like.
  • WiMax Worldwide Interoperability for Microwave Access
  • WLAN Wireless Local Area Network
  • CDMA Code Division Multiple Access
  • the prior art proposes a unified network discovery and selection concept, that is, after the user terminal UE accesses the network, an ANDSF (Access Network Discovery and Selection Function) in the network is accessed.
  • ANDSF Access Network Discovery and Selection Function
  • Network status information (such as load status, etc.) of the relevant access network
  • selecting the UE according to the relevant policies of the operator such as the access network mode available to the current UE
  • the signal conditions of the surrounding network collected by the UE.
  • a target network when the conditions are met, the user can switch to other access networks.
  • the UE may connect to the ANDSF through 3GPP access or trusted and untrusted non-3GPP access, and the ANDSF may connect to the non-3GPP access network to collect the load of the network. Information such as status.
  • the roaming UE when the roaming UE registers with the network, it can simultaneously select the vANDSF of the visited place and the hANDSF of the home location, and obtain relevant policy information and network status information from the hANDSF and the vANDSF respectively, and complete network discovery and selection processing.
  • the technical problem to be solved by the embodiments of the present invention is to provide a network discovery and selection method, a network system, and a communication device, which can more easily implement network discovery and selection processing.
  • the embodiment of the present invention provides a network discovery and selection method, including: after the user terminal accesses the network, the first access network discovery and selection function entity ANDSF acquires network status information by interacting with the second ANDSF; The ANDSF sends the acquired network status information to the user terminal for target network selection, or the acquired network status information is used by the user terminal to select a target network.
  • An embodiment of the present invention provides a network system, including: a first access network discovery and selection function entity ANDSF, configured to acquire network status information by interacting with a second ANDSF after the user terminal accesses the network, and the network is The status information is sent to the user terminal for target network selection, or the target network is selected for the user terminal according to the network status information; and the second access network discovery and selection function entity ANDSF is configured to perform with the first ANDSF Information exchange.
  • a first access network discovery and selection function entity ANDSF configured to acquire network status information by interacting with a second ANDSF after the user terminal accesses the network, and the network is The status information is sent to the user terminal for target network selection, or the target network is selected for the user terminal according to the network status information
  • the second access network discovery and selection function entity ANDSF is configured to perform with the first ANDSF Information exchange.
  • An embodiment of the present invention provides a communication apparatus, including: an interaction unit, configured to acquire network status information by interacting with another access network discovery and selection function entity ANDSF after the user terminal accesses the network; Sending the network status information to the user terminal for target network selection, or selecting a target network for the user terminal according to the network status information.
  • the network status information is obtained through interaction between the different access network discovery and the selection function entity ANDSF, so the user terminal only needs to access one of the network status information.
  • the ANDSF can obtain the network status information obtained after the information exchange on the network side through the ANDSF, and perform corresponding processing, or obtain the target network information selected according to the interaction result after the information exchange on the network side, thereby being more simple to implement. Network discovery and selection processing.
  • FIG. 1 is a schematic diagram of a network architecture according to Embodiment 1 of the present invention.
  • FIG. 2 is a flow chart of a method according to an embodiment of the present invention.
  • FIG. 3 is a flowchart of a UE actively initiating a request in a method according to an embodiment of the present invention
  • 4 is a flowchart of an ANDSF actively transmitting information to a UE in a method according to an embodiment of the present invention
  • FIG. 5 is a flowchart of a handover decision performed by a vANDSF in a method according to an embodiment of the present invention
  • FIG. 6 is a method according to Embodiment 1 of the present invention
  • a flowchart of the handover decision is completed by the hANDSF
  • FIG. 7 is a flowchart of the handover decision from the vANDSF to the hANDSF in the method according to the embodiment of the present invention
  • FIG. 8 is a schematic diagram of a network architecture according to Embodiment 2 of the present invention.
  • FIG. 10 is a flowchart of a UE actively initiating a request in a method according to Embodiment 2 of the present invention.
  • FIG. 11 is a flowchart of an ANDSF actively transmitting information to a UE in a method according to Embodiment 2 of the present invention
  • FIG. 12 is a flowchart of a handover decision performed by a vANDSF in a method according to Embodiment 2 of the present invention
  • FIG. 13 is a method according to Embodiment 2 of the present invention
  • FIG. 14 is a flowchart of a handover decision made by the hANDSF to the hANDSF in the method of the second embodiment of the present invention
  • FIG. 15 is a schematic diagram of a network architecture of Embodiment 3 of the present invention.
  • FIG. 17 is a schematic structural diagram of a network system according to an embodiment of the present invention.
  • FIG. 18 is a schematic structural diagram of a network system according to an embodiment of the present invention.
  • FIG. 19 is a schematic structural diagram of a communication apparatus according to an embodiment of the present invention.
  • the UE only needs to be connected to one of the ANDSFs to obtain relevant information, thereby facilitating network discovery and selection processing.
  • information interaction between the visited place and the ANDSF of the home place mainly has two forms, one is an interface for newly interacting between the vANDSF and the hANDSF, and information is exchanged, and the other way is to utilize the existing
  • the interface of the PCRF Policy Charging Rule Function
  • the vANDSF can be connected to the vPCRF
  • the vPCRF is connected to the hPCRF
  • the hANDSF can be connected to the hPCRF.
  • the interface of the interaction between the vANDSF and the hANDSF in the embodiment of the present invention is called Sz connection.
  • the ANDSF of the local network may be selected, that is, when the UE is at the home location, the hANDSF is selected, when the UE roams, the vANDSF is selected, and the selected ANDSF decides whether it is necessary to select one for the UE to pass the Sz.
  • the ANDSF of the interface connection When the UE accesses the system, the ANDSF of the local network may be selected, that is, when the UE is at the home location, the hANDSF is selected, when the UE roams, the vANDSF is selected, and the selected ANDSF decides whether it is necessary to select one for the UE to pass the Sz.
  • the ANDSF of the interface connection When the UE accesses the system, the ANDSF of the
  • the vANDSF may select the hANDSF for the identity of the UE, and the vANDSF and the hANDSF communicate through the Sz interface, and the UE only interacts with the directly connected vANDSF, and the vANDSF may be regarded as a proxy of the hANDSF.
  • FIG. 1 is a schematic diagram of a network architecture according to Embodiment 1 of the present invention.
  • vANDSF and hANDSF communicate through the new Sz interface; roaming UEs select vANDSF (when roaming selects the visited network, when roaming selects the home network).
  • the vANDSF communicates with the UE through the Sx interface; the hANDSF and the vANDSF obtain information such as the network status of other access systems in the network through the Sy interface.
  • hANDSF connects to vANDSF through the Sz interface, and obtains information such as the network status of the visited network through vANDSF.
  • FIG. 2 it is a flowchart of a method according to an embodiment of the present invention.
  • the UE is in the visited network and accesses the vANDSF.
  • FIG. 2 includes:
  • the UE performs a registration process to complete registration to a specific access network.
  • an attach procedure can be performed to register to a 3GPP network, a WiMax network, or the like.
  • the UE performs DNS (Domain Name Service) resolution or DHCP.
  • DNS Domain Name Service
  • the process obtains the address of the ANDSF, and the DNS server or the DHCP server returns the address of the configured ANDSF of the local network to the UE;
  • the ANDSF of the local network in which it is located is the vANDSF of the roaming place. If the address of the ANDSF of the local network in which the UE is located has been recorded in the UE, the DNS resolution or DHCP step does not need to be performed.
  • the UE initiates a registration process to the vANDSF, and requests a service from the vANDSF.
  • the registration process may be an explicit registration initiated by the UE, such as sending a registration request message to the vANDSF, or may be an implicit registration, such as the UE sending a policy request message to the vANDSF or sending a surrounding network. Measurement report of the network, etc. If the UE records the address of the home address hANDSF (which may be UE pre-configuration or network dynamic provisioning), the message carries the address of the hANDSF to the vANDSF.
  • the vANDSF can establish and maintain a context for the UE to record relevant information.
  • the vANDSF registers the UE to the hANDSF
  • the vANDSF finds that the UE is a roaming user, and according to the attribution information provided by the UE,
  • the UE selects a hANDSF, for example, may perform a DNS resolution according to the hPLMN ID of the UE (home Public Land Mobile Network) to obtain a hANDSF address, or a hANDSF address provided by the UE determines a hANDSF for the UE, and then The hANDSF initiates a registration procedure to register the UE with the hANDSF.
  • a DNS resolution according to the hPLMN ID of the UE (home Public Land Mobile Network) to obtain a hANDSF address, or a hANDSF address provided by the UE determines a hANDSF for the UE, and then The hANDSF initiates a registration procedure to register the UE with the hANDSF.
  • the registration process may be an explicit registration, such as the vANDSF sending a registration request message to the hANDSF; or an implicit registration, such as the vANDSF sending a policy request message to the hANDSF or transmitting a measurement report of the surrounding network.
  • the hANDSF can establish and maintain a context for the UE to record related information.
  • the 305 Perform related processing of network discovery and selection between the UE, the hANDSF, and the vANDSF.
  • the network discovery is different from the decision-making body of the selection, and can be divided into several situations.
  • the ANDSF provides policy information and/or related network state information to the UE, and the UE determines, according to the information provided by the ANDSF, whether handover needs to be made and which destination network to switch to.
  • the hANDSF sends the policy information related to the UE to the vANDSF
  • the vANDSF collects the status information of the related network according to the policy information provided by the hANDSF, and sends related policy information and network status information to the UE.
  • the UE can make a handover decision based on the information provided by the vANDSF, that is, decide whether a handover needs to be made and which destination network to switch to.
  • the process of the UE actively initiating a policy request after registering to the ANDSF is as shown in FIG. 3, including:
  • the UE sends a policy request message to the vANDSF to obtain policy information.
  • the vANDSF sends a policy request message to the hANDSF.
  • the vANDSF may obtain the network status from the relevant network, or may obtain the network status from the specific network according to the policy information provided by the hANDSF after step 403.
  • the hANDSF may send, according to the current location information of the UE, the policy information set by the home location (such as the network available for the visited place and the priority of the selection, etc.) to the vANDSF.
  • the policy information set by the home location such as the network available for the visited place and the priority of the selection, etc.
  • the vANDSF provides the UE with the policy information of the handover according to the policy information provided by the hANDSF and the status of the obtained related network.
  • the UE performs a decision according to the policy information sent by the vANDSF.
  • the UE can make a handover decision based on the information provided by the vANDSF, that is, whether or not switching needs to be made and which destination network to switch to.
  • the subsequent UE may send a policy request message to the vANDSF to obtain updated policy information, and the vANDSF and the hANDSF respectively obtain the updated information for processing.
  • the process of actively transmitting the policy information to the UE by one of the ANDSFs, for example, the hANDSF is as shown in FIG. 4, and includes:
  • the hANDSF may send, according to the current location information of the UE, the policy information set by the home location (such as the network available for the visited place and the priority of the selection, etc.) to the vANDSF;
  • the vANDSF provides the UE with the policy information of the handover according to the policy information provided by the hANDSF and the status of the obtained related network.
  • the UE performs a decision according to the policy information sent by the vANDSF.
  • the UE can make a handover decision based on the information provided by the vANDSF, that is, whether or not switching needs to be made and which destination network to switch to.
  • the vANDSF may also actively send policy information to the UE.
  • the hANDSF may send the updated policy information (such as the network available for the visited place and the selection priority, etc.) to the vANDSF.
  • the vANDSF may send the related information to the UE in the policy update message, and the UE completes the subsequent handover process according to the updated policy information.
  • the UE reports the measurement report of the neighboring network to the ANDSF, and the ANDSF performs the handover decision for the UE according to the handover policy of the UE and the measurement report reported by the UE, and sends the decision result to the UE, and the UE completes the result according to the result. Subsequent switching processing. In this case, the UE does not need to obtain the policy information sent by the ANDSF, and directly receives the decision result delivered by the ANDSF for processing.
  • the vANDSF is the final decision point of the handover
  • the hANDSF provides the vANDSF with the policy information required for the UE handover (such as the network available for the visit and the priority of the selection, etc.)
  • the vANDSF collects the state information of the relevant network (such as the current The load condition of the network)
  • the UE reports the measurement report of the surrounding network to the vANDSF.
  • the vANDSF performs a handover decision for the UE based on the information obtained above, and transmits a handover decision (e.g., to which target network to switch to) to the UE.
  • the UE sends a measurement report to the vANDSF.
  • the vANDSF sends a policy request message to the hANDSF.
  • a policy request message is sent to the hANDSF.
  • the vANDSF After receiving the measurement report of the UE, the vANDSF can immediately obtain the network status information from the relevant network. 603.
  • the hANDSF may send, according to the current location information of the UE, the policy information (such as the available network and the priority of the visit) to the vANDSF.
  • the vANDSF collects the status of the related network according to the policy information provided by the hANDSF, performs a handover decision, and sends the decision result to the UE, where the UE performs subsequent handover processing according to the decision result.
  • the related network status may be the information already saved in the vANDSF, or the vANDSF may initiate the status acquisition process to obtain the updated network status.
  • the vANDSF obtains the policy information provided by the hANDSF, which may be obtained through a separate process in steps 602 and 603, or may obtain the policy information provided by the hANDSF during the UE registration process.
  • the hANDSF may send the updated policy information (such as the network available for the visited place and the selection priority, etc.) to the vANDSF.
  • the vANDSF makes a handover decision for the UE, and sends a handover decision (such as which target network to switch to) to the UE.
  • the vANDSF cannot complete the handover decision, for example, when the UE is at the boundary of the visited network and is about to switch to another network, the access network controlled by the vANDSF cannot meet the handover requirement of the UE, and is required at this time.
  • the access network information of the other network is selected and sent to the UE to guide the UE to switch to the new network.
  • the vANDSF cannot obtain the information of the destination network, so the vANDSF needs the help of hANDSF, and can perform the following process:
  • the UE When the vANDSF is unable to complete the handover decision, the UE sends a policy request message to the hANDSF, requesting the hANDSF to provide access network resources of other networks (distinguished from the current visited network) where the current UE is located; hANDSF according to the current location of the UE, according to the operator policy Selecting available access network resource information of the other network (new visited network or home network) at the current location, and providing the status of the relevant access network, such as load status, through the vANDSF of the network where the access network is located, and The status of the information and access network is sent to the vANDSF that initiated the request. After receiving the information, the vANDSF performs a handover decision to select a handover target network for the UE. In addition, if the UE needs to migrate to the network, the hANDSF can directly obtain the access network status of the network, and does not need to obtain the information through the new vANDSF.
  • the hANDSF is the final handover decision point, and the vANDSF forwards the measurement report reported by the UE to the hANDSF, and reports the network status of the visited network to the hANDSF.
  • the UE sends a measurement report to the vANDSF.
  • the vANDSF forwards the measurement report to the hANDSF, where the message may also carry status information of the related network, such as a load status.
  • the hANDSF may perform a handover decision according to the measurement report reported by the UE, the status information of the related network that is provided by the vANDSF or saved in the hANDSF, and the operator policy, and select the destination network for the handover, and send the decision result to the vANDSF.
  • the hANDSF may also decide to switch to another visited network or a home network according to the measurement report reported by the UE.
  • the hANDSF may acquire available access network information from the vANDSF or the local hANDSF of the other visited network, and select an appropriate access network of the other visited network or the home network for the UE, and send the decision result to the vANDSF.
  • the vANDSF sends the decision result provided by the hANDSF to the UE, where the UE performs subsequent handover processing according to the decision result.
  • the hANDSF can still send the policy information to the vANDSF, and the vANDSF can report the network status according to the policy information (such as the subscribed access network and priority).
  • switching decisions may be made by hANDSF under certain circumstances.
  • the vANDSF fails to make a handover decision for the UE, the hANDSF is required to perform the handover decision, and the handover decision point is changed to hANDSF. After the hANDSF performs the handover decision, the decision result is sent to the UE through the vANDSF.
  • the UE sends a measurement report to the vANDSF.
  • the vANDSF cannot perform a handover decision for the UE, and then sends a handover request message to the hANDSF, requesting the hANDSF to perform a handover decision, where the handover request message may carry the measurement report provided by the UE;
  • the hANDSF returns a decision result to the vANDSF.
  • the hANDSF selects available access network resource information of other networks (other visited networks or home networks) of the current location according to the current location information of the UE, and provides related access through the vANDSF of the network where the access networks are located.
  • the status of the network such as the load status, performs a handover decision for the UE based on the measurement report provided by the UE, and sends the result of the handover decision to the vANDSF.
  • the vANDSF sends the decision result provided by the hANDSF to the UE, and the UE performs a subsequent handover operation according to the result.
  • This processing method is basically similar to the process of making decisions entirely by ANDSF, except that Before the UE reports the measurement report, the ANDSF needs to send the policy information to the UE first, and then the UE reports the measurement report according to the policy information.
  • the ANDSF described herein may be a vANDSF or a hANDSF 0 ANDSF, and may provide policy information to the UE during the first registration process of the UE, or actively provide the UE after the policy information changes.
  • the policy information provided by the ANDSF to the UE may generally include: a specified access network, a reported threshold or frequency, and the like.
  • the UE monitors the specified network according to the information. When the related data reaches the reporting threshold, the UE reports the measurement report of the specified network to the ANDSF.
  • the decision processing of ANDSF and the processing under the decision of ANDSF it is not consistent here.
  • the UE only needs to access the vANDSF, and the network status information obtained by the information exchange between the vANDSF and the hANDSF through the new interface is obtained by the vANDSF, thereby performing corresponding processing, or obtaining the vANDSF and the hANDSF.
  • the network information is selected based on the interaction result after the information is exchanged with the new interface, so that the network discovery and selection processing can be realized more simply.
  • FIG. 8 is a schematic diagram of a network architecture according to Embodiment 2 of the present invention.
  • the main difference between the network structure of the second embodiment and the first embodiment is that the UE in the second embodiment accesses the hANDSF.
  • the ANDSF of the home network can always be selected, and the selected hANDSF decides whether it is necessary to select an ANDSF that can be connected through the Sz interface for the UE.
  • the access network such as 3GPP or Wimax
  • the ANDSF of the home network can always be selected, and the selected hANDSF decides whether it is necessary to select an ANDSF that can be connected through the Sz interface for the UE.
  • hANDSF is selected.
  • the hANDSF can select a vANDSF of the visited network according to the current location of the UE and the like.
  • the vANDSF and the hANDSF communicate through the Sz interface, and the UE only interacts with the directly connected hANDSF, and the vANDSF can be hANDSF. Provide access network information, and even make switching decisions.
  • the network architecture of the second embodiment of the present invention describes the case where the UE registers with the hANDSF in the roaming condition. When the UE roams, the ANDSF of the home location is always found.
  • the vANDSF and hANDSF communicate via the new Sz interface.
  • the roaming UE selects the ANDSF of the home location, that is, hANDSF; the hANDSF communicates with the UE through the Sx interface; the vANDSF obtains information such as the network status of other access systems in the network through the Sy interface.
  • hANDSF connects to vANDSF through the Sz interface, and obtains information such as the network status of the visited network through vANDSF.
  • FIG. 9 is a flowchart of a method according to Embodiment 2 of the present invention.
  • the UE is roaming.
  • the hANDSF is accessed, so the flowchart of the second embodiment is basically the same as the process of the flowchart of the first embodiment, except that the positions of the vANDSF and the hANDSF in the flowchart change, and the corresponding flow produces some changes.
  • Figure 9 includes:
  • the UE performs a registration process to complete registration to a specific access network.
  • an attach procedure can be performed to register to a 3GPP network, a WiMax network, or the like.
  • the UE performs a DNS resolution or a DHCP process to obtain an address of the ANDSF from a DNS server or a DHCP server. If the address of the hANDSF has been recorded in the UE, the DNS resolution or DHCP step is not required to be performed.
  • the UE initiates a registration process to the hANDSF, and requests a service from the hANDSF.
  • the registration process may be an explicit registration initiated by the UE, such as sending a registration request message to the hANDSF, or an implicit registration, such as the UE sending a policy to the hANDSF. Request a message or send a measurement report of a surrounding network, etc.
  • the hANDSF can establish and maintain a context for the UE, recording relevant information.
  • the information (e.g., the PLMN ID of the visited network) selects a vANDSF for the visited location for the UE, and then initiates a registration procedure with the vANDSF to register the UE with the vANDSF.
  • the registration process may be an explicit registration, such as the hANDSF sending a registration request message to the vANDSF; or an implicit registration, such as the hANDSF sending a policy request message to the vANDSF or transmitting a measurement report of the surrounding network.
  • the vANDSF can establish and maintain a context for the UE to record relevant information.
  • the ANDSF provides policy information and/or related network state information to the UE, and the UE determines, according to the information provided by the ANDSF, whether handover needs to be made and which destination network to switch to.
  • the hANDSF provides policy information and/or related information to the UE.
  • the network status information (this information can be provided by the vANDSF to the hANDSF), and the UE can make a handover decision according to the information provided by the hANDSF, that is, whether the handover needs to be made and which destination network to switch to.
  • the process of the UE actively initiating a policy request after registering to the ANDSF is as shown in FIG. 10, including:
  • the UE sends a policy request message to the hANDSF to obtain policy information.
  • the message may include current location information of the UE, and the like.
  • the hANDSF After receiving the policy request message, the hANDSF sends a policy request message to the vANDSF to obtain the status of the related network.
  • the message sent to the vANDSF may include current location information of the UE, and may also include policy information provided by the hANDSF to the vANDSF.
  • the vANDSF may obtain the status of the network according to the current location information of the UE and/or the policy information provided by the hANDSF, and send the status to the hANDSF.
  • the hANDSF provides the UE with the switched policy information according to the policy information and the status of the related network provided by the vANDSF.
  • the UE performs a decision according to the policy information sent by the hANDSF.
  • the UE can make a handover decision based on the information provided by the hANDSF, that is, decide whether a handover needs to be made and which destination network to switch to.
  • the subsequent UE may send a policy request message to the hANDSF to obtain updated policy information, and the vANDSF and the hANDSF respectively obtain the updated information for processing.
  • the process of actively transmitting the policy information to the UE by one of the ANDSFs, for example, the vANDSF is as shown in FIG. 11, and includes:
  • the collected network status may be actively sent to the hANDSF;
  • the hANDSF provides the UE with the handover policy information according to the policy information and the status of the related network provided by the vANDSF; 1203.
  • the UE performs a decision according to the policy information sent by the hANDSF.
  • the UE can make a handover decision based on the information provided by the hANDSF, that is, decide whether a handover needs to be made and which destination network to switch to.
  • the hANDSF may also actively send the policy information to the UE.
  • the hANDSF may update the updated policy information (such as the network available at the visited place) And selecting the priority, etc.) and the network status are sent to the UE, and the UE completes the subsequent handover process according to the updated policy information.
  • the UE reports the measurement report of the neighboring network to the ANDSF, and the ANDSF performs the handover decision for the UE according to the handover policy of the UE and the measurement report reported by the UE, and sends the decision result to the UE, and the UE completes the result according to the result. Subsequent switching processing. In this case, the UE does not need to obtain the policy information sent by the ANDSF, and directly receives the decision result delivered by the ANDSF for processing.
  • vANDSF is the final decision point for the switch.
  • the UE reports the measurement report of the surrounding network to the hANDSF, and the hANDSF forwards the measurement report of the UE to the vANDSF and provides the policy information required for the UE handover (such as the network available for the visited place and the priority of the selection), and the vANDSF collects the status information of the related network. (such as the current network load situation).
  • the vANDSF performs a handover decision for the UE based on the information obtained above, and transmits a handover decision (e.g., to which target network to switch to) to the UE.
  • the UE sends a measurement report to the hANDSF.
  • the hANDSF forwards the measurement report to the vANDSF, where the message may also carry the location information of the current UE, and the policy information of the operator, and the like;
  • the vANDSF collects the status of the related network according to the location information and the policy information of the UE, and may also perform the handover decision by using the saved status information of the related network and the measurement report reported by the UE, and select the destination network for the handover for the UE, and The decision result is sent to hANDSF; 1304.
  • the hANDSF sends the decision result provided by the vANDSF to the UE, and the UE performs subsequent handover processing according to the decision result.
  • the hANDSF may send the updated policy information (such as the network available for the visited place and the selection priority, etc.) to the vANDSF.
  • the vANDSF makes a handover decision for the UE, and sends a handover decision (such as which target network to switch to) to the UE.
  • the vANDSF cannot complete the handover decision, for example, when the UE is at the boundary of the visited network and is about to switch to another network (other visited network or home network), the access network controlled by the vANDSF cannot satisfy The handover of the UE is required. At this time, the access network information of the other network needs to be selected and sent to the UE to guide the UE to switch to the new network. At this time, the vANDSF cannot obtain the information of the destination network, so the vANDSF needs the help of hANDSF and can be processed in the following two ways:
  • a processing method is: when the hANDSF receives the measurement report of the UE, and may determine the current UE in the existing visited network, the location information of the UE may be determined, and the other network according to the carrier policy is selected. Available access network resource information (other visited network or home network), and the status of the relevant access network, such as load status, can be provided through the vANDSF of the network where the access network is located, and then the policy information and the status of the access network are Send to vANDSF. After receiving the information, the vANDSF performs a handover decision to select a handover target network for the UE.
  • Another processing method is: when the vANDSF receives the measurement report sent by the hANDSF, and determines that the handover decision cannot be completed, sends a policy request message to the hANDSF, requesting the hANDSF to provide the other network where the current UE is located (distinguished from the current visited network) Access network resources of other visited networks or home networks; hANDSF selects available access network resource information of other networks in the current location according to the current location of the UE according to the current location of the UE, and can pass the vANDSF of the network where the access network is located Provides status of the associated access network, such as load conditions, and sends these policy information and the status of the access network to the vANDSF that initiated the request.
  • the vANDSF After receiving the information, the vANDSF performs a handover decision to select a handover target network for the UE. In addition, if the UE needs to migrate to the homing network, the hANDSF can directly obtain the access network status of the network without acquiring relevant information through the new vANDSF.
  • the hANDSF is the final handover decision point, and the hANDSF receives the measurement report reported by the UE, and requests the vANDSF to report the network status 4 of the visited network to the hANDSF.
  • the UE sends a measurement report to the hANDSF.
  • the hANDSF requests the vANDSF policy, and requests the vANDSF to provide policy information of the UE related network;
  • the vANDSF collects the status of the related network according to the location information and the policy information of the UE, and may also use the saved status information of the related network, and provide the network status to the hANDSF through the policy response message.
  • the hANDSF may perform a handover decision according to the measurement report reported by the UE, the status information of the related network provided by the vANDSF or saved in the hANDSF, and the operator policy, select a destination network for the handover, and send the decision result to the UE.
  • the UE performs subsequent handover processing according to the decision result.
  • step 1402 if the hANDSF adopts the stored network information, step 1402 and steps are performed.
  • the hANDSF may select another network for the UE according to the current location information of the UE.
  • the vANDSF of the other visited network or the home network and sends a policy request to the vANDSF (step 1402), requesting: obtaining information about the access network, and the newly selected vANDSF is based on the location information and policy information of the UE.
  • Etc. Collect the status of the relevant network and send it to hANDSF (as in step 1403).
  • the hANDSF can also directly obtain the information status of other access networks of the home network, and complete the decision.
  • the handover decision may be made by the hANDSF in some specific cases.
  • the hANDSF is required to perform the handover decision, and the handover decision point is changed to hANDSF.
  • the decision result is sent to the UE through the vANDSF.
  • the UE sends a measurement report to the vANDSF.
  • the hANDSF forwards the measurement report to the vANDSF, where the message may also carry the location information of the current UE, and the policy information of the operator;
  • the vANDSF fails to perform a handover decision for the UE, and sends a handover request message to the hANDSF, requesting the hANDSF to perform a handover decision, where the handover request message may carry the measurement report provided by the UE;
  • the hANDSF sends a decision result to the UE.
  • the hANDSF selects available access network resource information of other networks (other access networks or home networks) at the current location according to the current location information of the UE, and can provide related access through the vANDSF of the network where the access network is located.
  • the status of the network for example, the load status, performs a handover decision for the UE according to the measurement report provided by the UE, and sends the result of the handover decision to the UE, and the UE performs a subsequent handover operation according to the result.
  • the processing method is basically similar to the process of making the decision by the ANDSF.
  • the difference is that the ANDSF needs to send the policy information to the UE before the UE reports the measurement report, and then the UE reports the measurement report according to the policy information.
  • the ANDSF described herein may be a vANDSF or a hANDSF 0 ANDSF, and may provide policy information to the UE during the first registration process of the UE, or actively provide the UE after the policy information changes.
  • the policy information provided by the ANDSF to the UE may generally include: a specified access network, a reported threshold or frequency, and the like.
  • the UE monitors the specified network according to the information. When the related data reaches the reporting threshold, the UE reports the measurement report of the specified network to the ANDSF.
  • the decision processing of ANDSF and the processing under the decision of ANDSF it is not consistent here.
  • the UE only needs to access the hANDSF, and the network status information obtained by the information exchange between the hANDSF and the vANDSF through the new interface is obtained by the hANDSF, and corresponding processing is performed, or the hANDSF and the vANDSF are obtained.
  • the network information is selected based on the interaction result after the information is exchanged with the new interface, so that the network discovery and selection processing can be realized more simply.
  • FIG. 15 is a schematic diagram of a network architecture of Embodiment 3 of the present invention.
  • Embodiment 3 and Embodiment 1 The main difference between the network structure of the implementation two is that the implementation of the three interfaces between the vANDSF and the hANDSF does not set a new interface, but uses the interface between the PCRFs.
  • the ANDSF can be interfaced with the PCRF functional entity in the PCC (Policy Control and Charging) system, and the vPCRF of the roaming place and the hPCRF of the home location in the PCC architecture can be connected through the S9 interface. Therefore, the information exchange between the vANDSF and the hANDSF can also be implemented by using the interface.
  • the UE can select the ANDSF of the current network, and the ANDSF obtains the network policy information and the network status information through the vPCRF and the hPCRF, thereby completing the handover decision.
  • the ANDSF can obtain the current UE's policy information (such as the operator policy, the UE's service policy, and the like) from the PCRF, and can also obtain the information from another ANDSF by using the PCRF interface.
  • FIG. 15 only uses the UE to select the vANDSF as an example.
  • the UE may also select hANDSF and connect to the vANDSF through an interface between the hPCRF and the vPCRF.
  • a flowchart of a method according to Embodiment 3 of the present invention includes:
  • the UE performs a registration process to complete registration to a specific access network
  • an attach procedure can be performed to register to a 3GPP network, a WiMax network, or the like.
  • the UE performs a DNS resolution or a DHCP process to obtain an ANDSF address from a DNS server or a DHCP server, and the DNS server or the DHCP server will be configured.
  • the address of the ANDSF is returned to the UE;
  • the DNS resolution or DHCP step does not need to be performed.
  • the UE initiates a registration process to the vANDSF, and requests a service from the vANDSF.
  • the registration process may be an explicit registration initiated by the UE, such as sending a registration request message to the ANDSF, or may be an implicit registration, such as the UE sending a policy to the vANDSF. Request a message or send a measurement report of a surrounding network, etc.
  • the vANDSF can establish and maintain a context for the UE.
  • the vANDSF registers the UE to the hANDSF by using the vPCRF and the hPCRF. Corresponding processing of network discovery and selection between 1705, UE, hANDSF, vANDSF, vPCRF and hPCRF.
  • This step in this embodiment may also include three cases according to the difference between the network discovery and the selection decision body: that is, the decision is made entirely by the UE, the decision is made entirely by the ANDSF, and the UE and the ANDSF jointly decide.
  • the vANDSF requests the policy information from the vPCRF.
  • the PCRF can find the hPCRF according to the home network information of the UE, and forward the policy request sent by the vANDSF. If the hPCRF does not have the policy information of the UE, it sends a policy request to the hANDSF, requesting the hANDSF to provide related information.
  • the hANDSF may send the policy information (such as the available network and the selection priority) of the home location to the hPCRF according to the current location information of the UE, and the hPCRF sends the information obtained from the hANDSF to the vPCRF through the policy response message. And then forwarded to the vANDSF, and then the vANDSF sends the policy information to the UE, and the UE decides whether the handover is needed.
  • the UE only needs to access the vANDSF, and the network status information obtained by using the interface between the vANDSF and the hANDSF by using the existing PCRF interface is obtained by the vANDSF, so as to perform corresponding processing, or obtain the corresponding information.
  • the information about the target network selected by the vANDSF and the hANDSF after the information exchange between the existing PCRF interfaces is performed according to the interaction result, thereby enabling network discovery and selection processing to be more simple.
  • the embodiments provide a network system and apparatus.
  • FIG. 17 is a schematic structural diagram of a network system according to an embodiment of the present invention.
  • the network system includes: a first access network discovery and selection function entity ANDSF 1801, a second access network discovery and selection function entity ANDSF 1802.
  • the first access network discovery and selection function entity ANDSF 1801 is configured to acquire network status information by interacting with the second ANDSF 1802 after the user terminal accesses the network, and the network status information is used. Sending to the user terminal for target network selection, or selecting the network status information to select a target network for the user terminal.
  • the second access network discovery and selection function entity ANDSF 1802 is configured to perform information interaction with the first ANDSF 1801.
  • the first ANDSF 1801 specifically acquires network status information by interacting with the second ANDSF 1802 through a newly added signaling interface.
  • the first ANDSF 1801 is a visited vANDSF, and the second ANDSF 1802 is a home-based hANDSF; or the first ANDSF 1801 is a home-based hANDSF, and the second ANDSF 1802 is a visited vANDSF.
  • FIG. 18 it is a schematic structural diagram of a network system according to an embodiment of the present invention.
  • the network system includes: a first access network discovery and selection function entity ANDSF 1901, a second access network discovery and selection function entity ANDSF 1902, a home policy charging rule function entity hPCRF 1903, and a visited strategy. Charging rule function entity vPCRF 1904.
  • the first access network discovery and selection function entity ANDSF 1901 is configured to: after the user terminal accesses the network, acquire network condition information by interacting with the second ANDSF 1902, and send the network status information to the user terminal to perform the target.
  • the network selects or selects a target network for the user terminal according to the network status information.
  • the second access network discovery and selection function entity ANDSF 1902 is configured to perform information interaction with the first ANDSF 1901.
  • the first ANDSF 1901 specifically passes the home policy charging rule function entity hPCRF
  • An interface between the 1903 and the visited policy charging rule function entity vPCRF 1904 interacts with the second ANDSF 1902 to obtain network status information.
  • the first ANDSF 1901 is a visited vANDSF, and the second ANDSF 1902 is a home-based hANDSF; or the first ANDSF 1901 is a home-based hANDSF, and the second ANDSF 1902 is a visited vANDSF.
  • the specific connection between ANDSF and PCRF is: vANDSF is connected to vPCRF 1904, hANDSF is connected to hPCRF 1903, and the first ANDSF 1901 in FIG. 18 is connected to hPCRF 1903 for illustration.
  • FIG. 19 it is a schematic structural diagram of a communication device according to an embodiment of the present invention.
  • the communication device includes: an interaction unit 2002, and a processing unit 2003. Said here
  • the communication device may be an access network discovery and selection function entity ANDSF.
  • the interaction unit 2002 is configured to acquire network status information by interacting with the other access network discovery and selection function entity ANDSF after the user terminal accesses the network.
  • the processing unit 2003 is configured to send the network status information to the user terminal for target network selection, or select a target network for the user terminal according to the network status information.
  • the interaction unit 2002 interacts with the other access network discovery and selection function entity ANDSF to obtain network status information by using a newly added interface.
  • the interaction unit 2002 is configured by the home policy charging rule function entity hPCRF and The interface between the visited policy charging rule function entity vPCRF interacts with the other access network discovery and selection function entity ANDSF to obtain network status information.
  • the communication device further includes: a determination processing unit 2004.
  • the determining processing unit 2004 is configured to: after receiving the measurement report sent by the user terminal, determine that the target network cannot be selected for the user terminal, send a message to the other access network discovery and selection function entity ANDSF, requesting the The ANDSF selects a target network for the user terminal.
  • the communication device further includes: an indication unit 2005.
  • the indication unit 2005 is configured to send the policy information to the user terminal, and instruct the user terminal to report the measurement report according to the policy information.
  • the foregoing technical solution can be seen that, after the user terminal accesses the network in the technical solution of the embodiment of the present invention, the network status information is obtained through interaction between the different access network discovery and the selection function entity ANDSF, and thus the user terminal You only need to access one of the ANDSFs to pass the
  • the ANDSF obtains the network status information obtained after the information exchange on the network side, and performs corresponding processing, or obtains the target network information selected according to the interaction result after the information exchange on the network side, so that the network discovery and selection processing can be realized more simply.
  • the first ANDSF may interact with the second ANDSF to obtain network status information by using a newly added interface; or, the first ANDSF may adopt a home policy charging rule.
  • the interface between the functional entity hPCRF and the visited policy charging rule function entity vPCRF interacts with the second ANDSF to obtain network status information.
  • the technical solution of the embodiment of the present invention may be that the user terminal accesses the vANDSF of the visited place, or may be the hANDSF that accesses the attribution place.
  • the network discovery and selection method, the network system, and the communication device provided by the embodiments of the present invention are described in detail. For those skilled in the art, according to the embodiments of the present invention, in the specific implementation manner and application scope. There are variations, and the description is not to be construed as limiting the invention.

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Description

网络发现与选择方法、 网络***及通信装置
本申请要求于 2008 年 3 月 18 日提交中国专利局、 申请号为 200810084022.5、 发明名称为 "网络发现与选择方法、 网络***及装置" 的中 国专利申请的优先权， 其全部内容通过引用结合在本申请中。
技术领域
本发明涉及通信技术领域，具体涉及一种网络发现与选择方法、 网络*** 及通信装置。
背景技术
3GPP ( The 3rd Generation Partnership Project, 第三代伙伴计划）制定的 LTE ( Long Term Evolution, 长期演进计划） 中定义了新的移动通信网络的架 构， 称为 EPS ( evolved packet system, 演进的分组网络）。 EPS的重要特性是 考虑了多种接入方式的融合， 允许 non-3GPP (非 3GPP ) 的网络接入 EPS网 络， 这里所述的非 3GPP网络包括 WiMax ( Worldwide Interoperability for Microwave Access, 全球微波互联接入 )、 WLAN ( Wireless Local Area Network 无线局域网）、 CDMA ( Code Division Multiple Access, 码分多址）等。 出于运 营需要， 现有技术提出统一的网络发现与选择的设想， 即当用户终端 UE接入 网络后 , 通过网络中的一个 ANDSF ( Access Network Discovery and Selection Function,接入网发现与选择功能实体）收集相关接入网络的网络状况信息（如 负荷状况等）， 并根据运营商的相关策略（如当前 UE可用的接入网方式）和 利用 UE收集的周边网络的信号情况等共同为 UE选择一个目标网络， 当条件 符合时， 用户可以切换到其他的接入网中。
现有技术的网络发现与选择的架构中， UE可以通过 3GPP接入或可信以 及不可信的非 3GPP接入方式连接到 ANDSF, 而 ANDSF可以连接到非 3GPP 接入网络， 从而收集网络的负荷状况等信息。 在该架构下， 漫游的 UE注册到 网络时可以同时选择拜访地的 vANDSF和归属地的 hANDSF ,分别从 hANDSF 和 vANDSF获取相关策略信息以及网络状况信息， 完成网络发现与选择处理。
在对现有技术的研究和实践过程中 , 发明人发现现有技术存在以下问题： 现有技术的架构和方法， UE总是需要选择两个 ANDSF进行交互处理， 过程过于复杂， 适用性不强。 发明内容
本发明实施例要解决的技术问题是提供一种网络发现与选择方法、网络系 统及通信装置， 能更简单的实现网络发现与选择处理。
为解决上述技术问题， 本发明所提供的实施例是通过以下技术方案实现 的：
本发明实施例提供一种网络发现与选择方法， 包括：在用户终端接入网络 后， 第一接入网发现与选择功能实体 ANDSF通过与第二 ANDSF的交互获取 网络状况信息； 所述第一 ANDSF将所述获取的网络状况信息发送给所述用户 终端进行目标网络选择，或者 ^居所述获取的网络状况信息为所述用户终端选 择目标网络。
本发明实施例提供一种网络***， 包括： 第一接入网发现与选择功能实体 ANDSF,用于在用户终端接入网络后，通过与第二 ANDSF的交互获取网络状 况信息，将所述网络状况信息发送给所述用户终端进行目标网络选择，或者根 据所述网络状况信息为所述用户终端选择目标网络；第二接入网发现与选择功 能实体 ANDSF, 用于与所述第一 ANDSF进行信息交互。
本发明实施例提供一种通信装置， 包括： 交互单元， 用于在用户终端接入 网络后 , 通过与其他的接入网发现与选择功能实体 ANDSF的交互获取网络状 况信息； 处理单元，用于将所述网络状况信息发送给所述用户终端进行目标网 络选择， 或者根据所述网络状况信息为所述用户终端选择目标网络。
上述技术方案可以看出， 本发明实施例技术方案中在用户终端接入网络 后， 通过在不同的接入网发现与选择功能实体 ANDSF间交互获取网络状况信 息， 因此用户终端只需要访问其中一个 ANDSF, 就可以通过该 ANDSF获取 网络侧进行信息交互后得到的网络状况信息，从而进行相应处理，或者获取到 网络侧进行信息交互后根据交互结果选择出的目标网络信息，从而能够更简单 的实现网络发现与选择处理。
附图说明
图 1是本发明实施例一网络架构示意图；
图 2是本发明实施例一方法流程图；
图 3是本发明实施例一方法中 UE主动发起请求的流程图； 图 4是本发明实施例一方法中 ANDSF主动向 UE下发信息的流程图； 图 5是本发明实施例一方法中由 vANDSF完成切换决策的流程图； 图 6是本发明实施例一方法中由 hANDSF完成切换决策的流程图； 图 7是本发明实施例一方法中由 vANDSF转为 hANDSF完成切换决策的 流程图；
图 8是本发明实施例二网络架构示意图；
图 9是本发明实施例二方法流程图；
图 10是本发明实施例二方法中 UE主动发起请求的流程图；
图 11是本发明实施例二方法中 ANDSF主动向 UE下发信息的流程图； 图 12是本发明实施例二方法中由 vANDSF完成切换决策的流程图； 图 13是本发明实施例二方法中由 hANDSF完成切换决策的流程图； 图 14是本发明实施例二方法中由 vANDSF转为 hANDSF完成切换决策的 流程图；
图 15是本发明实施例三网络架构示意图；
图 16是本发明实施例三方法流程图；
图 17是本发明实施例网络***一结构示意图；
图 18是本发明实施例网络***二结构示意图；
图 19是本发明实施例通信装置结构示意图。
具体实施方式
本发明实施例中通过在拜访地和归属地的 ANDSF间进行信息的交互， 则
UE只需要与其中一个 ANDSF进行相连， 就可以获得相关信息， 从而更简单 的实现网络发现与选择处理。
本发明实施例中在拜访地和归属地的 ANDSF间进行信息的交互主要有两 种形式， 一种是 vANDSF和 hANDSF之间新增交互的接口 , 进行信息交互， 另外一种方式是利用现有技术中 PCRF ( Policy Charging Rule Function, 策略 计费规则功能实体） 的接口， 即归属地的 hPCRF与拜访地的 vPCRF间的 S9 接口， vANDSF可与 vPCRF连接， vPCRF与 hPCRF连接， hANDSF可与 hPCRF 连接， 从而进行信息交互。
本发明实施例在 vANDSF和 hANDSF之间设置的交互的接口称为 Sz接 口， 通过该接口， vANDSF和 hANDSF之间可以传递切换策略、 切换决策、 接入网状态信息等。 当 UE接入***时， 可以选择本地网络的 ANDSF, 即当 UE在归属地时， 选择 hANDSF, 当 UE漫游时， 选择 vANDSF, 并由该选择 的 ANDSF决策是否还需要为 UE选择一个可以通过 Sz接口连接的 ANDSF。 例如当 UE在漫游时， vANDSF 可以 UE 的标识为其选择 hANDSF, vANDSF和 hANDSF通过 Sz接口通信 , UE只是与直接相连的 vANDSF交互， 此时 vANDSF可以看作 hANDSF的一个代理。
以下方法是以漫游场景下的处理举例说明，但不局限与此， 非漫游场景下 也是同样适用的。
请参阅图 1 , 是本发明实施例一网络架构示意图。
如图 1所示， vANDSF和 hANDSF通过新增的 Sz接口进行通信； 漫游的 UE 选择 vANDSF (漫游时选择拜访地网络， 非漫游时选择归属地网络）。 vANDSF通过 Sx接口和 UE进行通信； hANDSF和 vANDSF通过 Sy接口获 取本网络中其他接入***的网络状况等信息。 hANDSF 通过 Sz接口连接到 vANDSF , 并通过 vANDSF获取拜访网络的网络状况等信息。
请参阅图 2， 是本发明实施例一方法流程图， 实施例一中 UE是处于拜访 地网络中， 访问 vANDSF, 图 2中包括：
301、 UE执行注册流程完成到特定接入网络的注册；
例如可以执行附着流程注册到 3GPP网络、 WiMax网络等。
302、 UE执行 DNS ( Domain Name Service, 域名服务）解析或 DHCP
( Dynamic Host Configuration Protocol, 动态主机配置协议 ) 流程获取 ANDSF 的地址， DNS服务器或 DHCP服务器将配置的本地网络的 ANDSF的地址返 回给 UE;
当 UE漫游时， 所处的本地网络的 ANDSF即为漫游地的 vANDSF。 如果 UE中已经记录所处的本地网络的 ANDSF的地址 ,则不需要执行该 DNS解析 或 DHCP步骤。
303、 UE发起到 vANDSF的注册流程， 向 vANDSF请求服务；
该注册流程可以是 UE发起的显式注册，如向 vANDSF发送注册请求消息； 也可以是一个隐式的注册，如 UE向 vANDSF发送策略请求消息或发送周边网 络的测量报告等。如果 UE记录了归属地 hANDSF的地址（可以是 UE预配置 或网络动态提供）， 则在消息中携带 hANDSF的地址给 vANDSF。
该 vANDSF可以为 UE建立并维护一个上下文， 记录相关信息。
304、 vANDSF将 UE注册到 hANDSF;
vANDSF发现该 UE是一个漫游用户， 则根据 UE提供的归属地信息为该
UE选择一个 hANDSF, 例如可以根据 UE的 hPLMN ID ( home Public Land Mobile Network, 归属地公共陆地移动网标识）进行 DNS解析得到 hANDSF 地址， 或者 UE提供的 hANDSF地址为该 UE确定一个 hANDSF, 然后向 该 hANDSF发起注册流程， 将该 UE注册到该 hANDSF。
该注册流程可以是一个显式注册， 如 vANDSF向 hANDSF发送注册请求 消息； 也可以是一个隐式的注册， 如 vANDSF向 hANDSF发送策略请求消息 或发送周边网络的测量报告等。
该 hANDSF可以为 UE建立并维护一个上下文， 记录相关信息。
305、 UE、 hANDSF和 vANDSF之间进行网络发现与选择的相关处理。 该步骤中， ^居网络发现与选择的决策主体不同，具体又可以分为几种情 况。
1 )完全由 UE进行决策时的处理
在该切换决策方法下， ANDSF向 UE提供策略信息和 /或相关网络状态信 息， UE根据 ANDSF提供的信息判断是否需要发生切换以及切换到哪个目的 网络。
因此， 在本发明实施例架构下， hANDSF将该 UE相关的策略信息发送给 vANDSF , vANDSF根据 hANDSF提供的策略信息收集相关网络的状况信息， 并将相关的策略信息和网络状况信息发送给 UE。 UE可以根据 vANDSF提供 的信息进行切换决策， 即决定是否需要发生切换以及切换到哪个目的网络。
此时又可以分为 UE主动发起策略请求的情况和网络侧主动下发策略信息 的情况。
UE在注册到 ANDSF (包括注册到 vANDSF和 hANDSF )之后主动发起 策略请求的过程如图 3所示， 包括：
401、 UE向 vANDSF发送策略请求消息， 以获取策略信息； 402、 vANDSF收到该策略请求消息后， 向 hANDSF发送策略请求消息； 这期间 , vANDSF可以向相关网络获取网络状况 ,也可以在步骤 403之后 根据 hANDSF提供的策略信息再向特定网络获取网络状况。
403、 hANDSF可以根据 UE当前的位置信息将归属地设置的策略信息（如 该拜访地可用的网络及选择优先级等 )发送给 vANDSF;
404、 vANDSF根据 hANDSF提供的策略信息和获取的相关网络的状况， 向 UE提供切换的策略信息；
405、 UE根据 vANDSF发送的策略信息进行决策。
UE可以根据 vANDSF提供的信息进行切换决策， 即决定是否需要发生切 换以及切换到哪个目的网络。
需要说明的是，后续 UE可以再向 vANDSF发送策略请求消息， 以获取更 新的策略信息， 则 vANDSF和 hANDSF分别获取更新后的信息进行处理。
在 UE注册到 ANDSF (包括注册到 vANDSF和 hANDSF )之后， 由其中 的一个 ANDSF例如 hANDSF主动向 UE发送策略信息的流程如图 4所示， 包 括：
501、 hANDSF可以根据 UE当前的位置信息将归属地设置的策略信息（如 该拜访地可用的网络及选择优先级等 )发送给 vANDSF;
502、 vANDSF根据 hANDSF提供的策略信息和获取的相关网络的状况， 向 UE提供切换的策略信息；
503、 UE根据 vANDSF发送的策略信息进行决策。
UE可以根据 vANDSF提供的信息进行切换决策， 即决定是否需要发生切 换以及切换到哪个目的网络。
需要说明的是， 也可以由 vANDSF主动向 UE发送策略信息。 另外， 当归 属地和漫游地的漫游协议发生改变或该 UE 的相关策略信息发生改变， 则 hANDSF可以将更新的策略信息（如该拜访地可用的网络及选择优先级等 )发 送给 vANDSF。 vANDSF收到 hANDSF提供的策略更新信息或者检查到相关 网络状况发生改变后， 可以将相关信息包括在策略更新消息中发送给 UE, 由 UE按照更新后的策略信息完成后续切换处理。
2 )完全由 ANDSF进行决策时的处理。 在该切换决策方法下， UE向 ANDSF上报周边网络的测量报告， ANDSF 根据该 UE的切换策略以及 UE上报的测量报告， 为 UE进行切换决策， 并将 决策结果发送给 UE, UE按照该结果完成后续的切换处理。 此情况下， UE可 以不需要获取 ANDSF发送的策略信息， 直接接收 ANDSF下发的决策结果进 行处理。
在该切换决策方法下， 由于为 UE服务的 ANDSF 实际上存在两个， 即 vANDSF和 hANDSF，因此，可以根据切换决策点的不同又分为如下三种情况： A: 完全由 vANDSF完成切换决策
在该场景下， vANDSF是切换的最终决策点， hANDSF向 vANDSF提供 该 UE 切换所需的策略信息 （如该拜访地可用的网络及选择优先级等）， vANDSF收集相关网络的状态信息（如当前网络的负荷情况）， UE向 vANDSF 上报周边网络的测量报告。 vANDSF根据上述获得的信息， 为该 UE执行切换 决策， 并将切换决策（如切换到哪个目标网络）发送给 UE。
由 vANDSF完成切换决策具体过程请参阅图 5所示， 包括：
601、 UE向 vANDSF发送测量报告；
602、 vANDSF向 hANDSF发送策略请求消息；
如果 vANDSF中没有记录 hANDSF提供的策略信息，则向 hANDSF发送 策略请求消息。
vANDSF收到 UE的测量4艮告后，可以立即向相关网络获取网络状况信息。 603、 hANDSF可以根据 UE当前的位置信息将归属地设置的策略信息（如 该拜访地可用的网络及选择优先级等 )发送给 vANDSF;
604、 vANDSF根据 hANDSF提供的策略信息， 收集相关网络的状况， 进 行切换决策， 并将决策结果发送给 UE, 由 UE根据决策结果执行后续的切换 处理。
其中所述的相关网络状况可以采用 vANDSF 中已经保存的信息， 也可以 由 vANDSF向相关网络发起状态获取流程获取更新的网络状况。
需要说明的是， vANDSF获取 hANDSF提供的策略信息可以是如步骤 602 和 603 中通过单独的流程获取， 也可以是在 UE 注册过程中就已经获取 hANDSF提供的策略信息。 另外， 当归属地和漫游地的漫游协议发生改变或该 UE的相关策略信息发 生改变， 则 hANDSF可以将更新的策略信息（如该拜访地可用的网络及选择 优先级等 )发送给 vANDSF。 vANDSF根据上述获得的信息以及运营商的相关 策略， 为该 UE进行切换决策， 并将切换决策（如切换到哪个目标网络）发送 给 UE。
如果在某些情况下， vANDSF不能完成切换决策， 例如当 UE处于该拜访 网络的边界处而正要切换到其他网络时， vANDSF所控制的接入网络并不能满 足 UE的切换需要， 此时需要为该 UE选择一个其他网络的接入网信息发送给 UE, 以指导 UE切换到新的网络。 此时， vANDSF不能获得该目的网络的信 息， 因此 vANDSF需要 hANDSF的帮助， 可以进行以下过程：
当 vANDSF无法完成切换决策时， 向 hANDSF发送策略请求消息， 要求 hANDSF提供当前 UE所处位置其他网络（区别于当前的拜访网络）的接入网 资源； hANDSF根据 UE当前的位置， 根据运营商策略， 选择当前位置其他网 络（新的拜访网络或归属网络）的可用接入网资源信息， 并可以通过这些接入 网所在网络的 vANDSF提供相关接入网的状况 , 例如负荷状况 , 并将这些策 略信息和接入网的状况发送给发起请求的 vANDSF。 vANDSF收到这些信息后 执行切换决策， 为 UE选择一个切换的目标网络。 另外， 如果 UE需要迁回归 属网络， 则 hANDSF可以直接获取本网络的接入网状况， 而不需要通过新的 vANDSF获:^目关信息。
B: 完全由 hANDSF完成切换决策
在该场景下， hANDSF是最终的切换决策点， vANDSF向 hANDSF转发 UE上报的测量报告 , 并将拜访网络相关的网络状态报告给 hANDSF。
由 hANDSF完成切换决策具体过程请参阅图 6所示， 包括：
701、 UE向 vANDSF发送测量报告；
702、 vANDSF向 hANDSF转发测量报告， 该消息中同时也可以携带相关 网络的状态信息， 如负荷状况等；
703、 hANDSF可以根据 UE上报的测量报告， vANDSF提供的或保存在 hANDSF中的相关网络的状态信息以及运营商策略等执行切换决策，为 UE选 择切换的目的网络， 并将决策结果发送给 vANDSF; 在该步骤中， hANDSF也可以根据 UE上报的测量报告， 决策需要切换到 其他拜访网络或归属网络。 此时， hANDSF 可以向其他拜访网络的 vANDSF 或本 hANDSF获取可用的接入网信息，并为该 UE选择一个合适的其他拜访网 络或归属网络的接入网， 并将该决策结果发送给 vANDSF。
704、 vANDSF将 hANDSF提供的决策结果发送给 UE, 由 UE根据决策 结果执行后续的切换处理。
在该方法下， 当 UE初始注册时， hANDSF依然可以将策略信息发送给 vANDSF, vANDSF可以根据策略信息（如签约的接入网及优先级等）来上报 网络状况。
C: 由 vANDSF转为 hANDSF完成切换决策
在由 vANDSF进行切换决策时， 在某些特定情况下可能转由 hANDSF进 行切换决策。 当 vANDSF无法为 UE进行切换决策时， 要求 hANDSF进行切 换决策， 切换决策点改为 hANDSF, 在 hANDSF进行切换决策后， 将决策结 果通过 vANDSF发送给 UE。
由 vANDSF转为 hANDSF完成切换决策具体过程请参阅图 7所示，包括：
801、 UE向 vANDSF发送测量报告；
802、 vANDSF无法为 UE进行切换决策， 则向 hANDSF发送切换请求消 息，要求 hANDSF进行切换决策，该切换请求消息中可以携带 UE提供的测量 报告；
803、 hANDSF向 vANDSF返回决策结果；
hANDSF根据 UE当前的位置信息， 根据运营商策略， 选择当前位置其他 网络（其他的拜访网络或归属网络）的可用接入网资源信息， 并可以通过这些 接入网所在网络的 vANDSF提供相关接入网的状况 , 例如负荷状况 , 根据 UE 提供的测量报告， 为该 UE 执行切换决策， 并将切换决策的结果发送给 vANDSF。
804、 vANDSF将 hANDSF提供的决策结果发送给 UE, 由 UE根据该结 果执行后续的切换操作。
3 ) 由 UE和 ANDSF共同进行决策
该处理方法和完全由 ANDSF进行决策的流程基本类似， 不同之处在于， 当 UE上报测量报告之前， ANDSF需要先向 UE发送策略信息， 然后 UE根据 该策略信息上报测量报告。 这里所述的 ANDSF 可以是 vANDSF, 也可以是 hANDSF 0 ANDSF—般可以在 UE第一次注册过程中向 UE提供策略信息，或 者当策略信息发生改变后主动向 UE提供。
ANDSF向 UE提供的策略信息一般可以包括： 指定的接入网、 上报的门 限或频率等。 UE根据这些信息对指定网络进行监控， 当相关数据达到上报门 限时， 向 ANDSF上报指定网络的测量报告。 至于 ANDSF的决策处理和完全 由 ANDSF决策下的处理过程是一致的， 此处不再赞述。
本发明实施例一中， UE只需要访问 vANDSF, 就可以通过该 vANDSF获 取由 vANDSF与 hANDSF间利用新增接口进行信息交互后得到的网络状况信 息 , 从而进行相应处理 , 或者获取到由 vANDSF与 hANDSF间利用新增接口 进行信息交互后根据交互结果选择出的目标网络信息，从而能够更简单的实现 网络发现与选择处理。
请参阅图 8， 是本发明实施例二网络架构示意图。 实施例二和实施例一的 网络结构的主要区别是实施例二中 UE是访问 hANDSF。
当 UE注册到接入网络（如 3GPP或 Wimax )后， 可以总是选择归属网络 的 ANDSF, 并由该选择的 hANDSF决策是否还需要为 UE选择一个可以通过 Sz接口连接的 ANDSF。 特别是当 UE漫游时选择了 hANDSF, 该 hANDSF可 以根据 UE的当前位置等信息为其选择一个拜访网络的 vANDSF, vANDSF和 hANDSF通过 Sz接口通信， UE只是与直接相连的 hANDSF交互， vANDSF 可以为 hANDSF提供接入网信息， 甚至进行切换决策等。
本发明实施例二网络架构描述的是 UE在漫游状况下注册到 hANDSF的情 况， 当 UE为发生漫游时， 总是找到归属地的 ANDSF。
如图 8所示， vANDSF和 hANDSF之间通过新增的 Sz接口进行通信。 漫 游的 UE选择归属地的 ANDSF即 hANDSF; hANDSF通过 Sx接口和 UE进行 通信； vANDSF通过 Sy接口获取本网络中其他接入***的网络状况等信息。 此外 , hANDSF通过 Sz接口连接到 vANDSF , 并通过 vANDSF获取拜访网络 的网络状况等信息。
请参阅图 9, 是本发明实施例二方法流程图， 实施例二中 UE是处于漫游 网络中，访问 hANDSF, 因此实施例二流程图与实施例一流程图的过程基本相 同， 只是 vANDSF和 hANDSF在流程图中的位置发生变化 , 相应的流程产生 一些变化。 图 9中包括：
1001、 UE执行注册流程完成到特定接入网络的注册；
例如可以执行附着流程注册到 3GPP网络、 WiMax网络等。
1002、 UE执行 DNS解析或 DHCP流程向 DNS服务器（ DNS Server )或 DHCP服务器获取 ANDSF的地址， 如果 UE中已经记录 hANDSF的地址， 则 不需要执行该 DNS解析或 DHCP步骤。
1003、 UE发起到 hANDSF的注册流程， 向 hANDSF请求服务； 该注册流程可以是 UE发起的显式注册，如向 hANDSF发送注册请求消息； 也可以是一个隐式的注册，如 UE向 hANDSF发送策略请求消息或发送周边网 络的测量报告等。该 hANDSF可以为 UE建立并维护一个上下文，记录相关信 „
Figure imgf000013_0001
信息（如拜访网络的 PLMN ID )为该 UE选择一个拜访地的 vANDSF, 然后 向该 vANDSF发起注册流程 , 将该 UE注册到该 vANDSF。
该注册流程可以是一个显式注册， 如 hANDSF向 vANDSF发送注册请求 消息； 也可以是一个隐式的注册， 如 hANDSF向 vANDSF发送策略请求消息 或发送周边网络的测量报告等。
该 vANDSF可以为 UE建立并维护一个上下文， 记录相关信息。
1005、 UE、 hANDSF和 vANDSF之间进行网络发现与选择的相关处理。 该步骤中，根据网络发现与选择的决策主体不同，具体又可以分为几种情 况。
1 )完全由 UE进行决策时的处理
在该切换决策方法下， ANDSF向 UE提供策略信息和 /或相关网络状态信 息， UE根据 ANDSF提供的信息判断是否需要发生切换以及切换到哪个目的 网络。
因此， 在本发明实施例架构下， hANDSF向 UE提供策略信息和 /或相关 网络状态信息 （该信息可以由 vANDSF 提供给 hANDSF ), UE 可以根据 hANDSF提供的信息进行切换决策，即决定是否需要发生切换以及切换到哪个 目的网络。
此时又可以分为 UE主动发起策略请求的情况和网络侧主动下发策略信息 的情况。
UE在注册到 ANDSF (包括注册到 vANDSF和 hANDSF )之后主动发起 策略请求的过程如图 10所示， 包括：
1101、 UE向 hANDSF发送策略请求消息， 以获取策略信息；
该消息中可以包括 UE当前的位置信息等。
1102, hANDSF收到该策略请求消息后， 向 vANDSF发送策略请求消息 以获取相关网络的状况；
向 vANDSF发送的该消息中可以包括 UE当前的位置信息， 也可以包括 hANDSF向 vANDSF提供的策略信息。
1103、 vANDSF可以才艮据 UE当前的位置信息和 /或 hANDSF提供的策略 信息获 目关网络的状态， 并发送给 hANDSF;
1104、 hANDSF根据策略信息以及 vANDSF提供的相关网络的状况， 向 UE提供切换的策略信息；
1105、 UE根据 hANDSF发送的策略信息进行决策。
UE可以根据 hANDSF提供的信息进行切换决策， 即决定是否需要发生切 换以及切换到哪个目的网络。
需要说明的是，后续 UE可以再向 hANDSF发送策略请求消息， 以获取更 新的策略信息， 则 vANDSF和 hANDSF分别获取更新后的信息进行处理。
UE在注册到 ANDSF (包括注册到 vANDSF和 hANDSF )之后， 由其中 的一个 ANDSF例如 vANDSF主动向 UE发送策略信息的流程如图 11所示， 包括：
1201、 当 vANDSF判断当前 UE的相关网络状况发生改变后，可以将收集 的网络状况主动发送给 hANDSF;
1202、 hANDSF根据策略信息以及 vANDSF提供的相关网络的状况， 向 UE提供切换的策略信息； 1203、 UE根据 hANDSF发送的策略信息进行决策。
UE可以根据 hANDSF提供的信息进行切换决策， 即决定是否需要发生切 换以及切换到哪个目的网络。
需要说明的是， 也可以由 hANDSF主动向 UE发送策略信息。 另外， 当归 属地和漫游地的漫游协议发生改变或该 UE 的相关策略信息发生改变， 或者 vANDSF指示 UE当前相关网络状况发生改变， 则 hANDSF可以将更新的策 略信息 （如该拜访地可用的网络及选择优先级等）和网络状况发送给 UE, 由 UE按照更新后的策略信息完成后续切换处理。
2 )完全由 ANDSF进行决策时的处理。
在该切换决策方法下， UE向 ANDSF上报周边网络的测量报告， ANDSF 根据该 UE的切换策略以及 UE上报的测量报告， 为 UE进行切换决策， 并将 决策结果发送给 UE, UE按照该结果完成后续的切换处理。 此情况下， UE可 以不需要获取 ANDSF发送的策略信息， 直接接收 ANDSF下发的决策结果进 行处理。
在该切换决策方法下， 由于为 UE服务的 ANDSF 实际上存在两个， 即 vANDSF和 hANDSF，因此，可以根据切换决策点的不同又分为如下三种情况： A: 完全由 vANDSF完成切换决策
在该场景下， vANDSF是切换的最终决策点。 UE向 hANDSF上报周边网 络的测量报告， hANDSF向 vANDSF转发 UE的测量 告并提供该 UE切换所 需的策略信息（如该拜访地可用的网络及选择优先级等）， vANDSF收集相关 网络的状态信息（如当前网络的负荷情况）。 vANDSF根据上述获得的信息， 为该 UE执行切换决策， 并将切换决策（如切换到哪个目标网络）发送给 UE。
由 vANDSF完成切换决策具体过程请参阅图 12所示， 包括：
1301、 UE向 hANDSF发送测量报告；
1302, hANDSF向 vANDSF转发测量报告 , 该消息中也可以携带当前 UE 的位置信息， 以及运营商的策略信息等；
1303、 vANDSF根据 UE的位置信息和策略信息等收集相关网络的状况， 也可以采用保存的相关网络的状况信息， 以及 UE上报的测量报告等进行切换 决策， 为 UE选择切换的目的网络， 并将决策结果发送给 hANDSF; 1304、 hANDSF将 vANDSF提供的决策结果发送给 UE, 由 UE根据决策 结果执行后续的切换处理。
另外， 当归属地和漫游地的漫游协议发生改变或该 UE的相关策略信息发 生改变， 则 hANDSF可以将更新的策略信息（如该拜访地可用的网络及选择 优先级等 )发送给 vANDSF。 vANDSF根据上述获得的信息以及运营商的相关 策略， 为该 UE进行切换决策， 并将切换决策（如切换到哪个目标网络）发送 给 UE。
如果在某些情况下， vANDSF不能完成切换决策， 例如当 UE处于该拜访 网络的边界处而正要切换到其他网络（其他拜访网络或归属网络）时， vANDSF 所控制的接入网络并不能满足 UE的切换需要， 此时需要为该 UE选择一个其 他网络的接入网信息发送给 UE， 以指导 UE切换到新的网络。此时， vANDSF 不能获得该目的网络的信息， 因此 vANDSF需要 hANDSF的帮助， 可以通过 以下两种方式进行处理：
一种处理方式是， 当 hANDSF收到 UE的测量报告后， 可以 UE的位 置信息等情况， 判断出当前 UE在现有的拜访网络中不能正常工作， 则根据运 营商策略， 选择当前位置其他网络（其他拜访网络或归属网络）的可用接入网 资源信息， 并可以通过这些接入网所在网络的 vANDSF提供相关接入网的状 况， 例如负荷状况， 然后将这些策略信息和接入网的状况发送给 vANDSF。 vANDSF收到这些信息后执行切换决策， 为 UE选择一个切换的目标网络。
另外一种处理方式是， 当 vANDSF接收到 hANDSF发送的测量报告后， 判断出无法完成切换决策时， 向 hANDSF发送策略请求消息， 要求 hANDSF 提供当前 UE所处位置其他网络（区别于当前的拜访网络的其他拜访网络或归 属网络）的接入网资源； hANDSF根据 UE当前的位置， 根据运营商策略， 选 择当前位置其他网络的可用接入网资源信息，并可以通过这些接入网所在网络 的 vANDSF提供相关接入网的状况， 例如负荷状况， 并将这些策略信息和接 入网的状况发送给发起请求的 vANDSF。 vANDSF收到这些信息后执行切换决 策， 为 UE选择一个切换的目标网络。 另外， 如果 UE需要迁回归属网络， 则 hANDSF可以直接获取本网络的接入网状况， 而不需要通过新的 vANDSF获 取相关信息。 B: 完全由 hANDSF完成切换决策
在该场景下， hANDSF是最终的切换决策点， hANDSF接收 UE上报的测 量报告 , 并要求 vANDSF将拜访网络相关的网络状态4艮告给 hANDSF。
由 hANDSF完成切换决策具体过程请参阅图 13所示， 包括：
1401、 UE向 hANDSF发送测量报告；
1402、 hANDSF向 vANDSF策略请求， 要求 vANDSF提供该 UE相关网 络的策略信息；
1403、 vANDSF根据 UE的位置信息和策略信息等收集相关网络的状况， 也可以采用保存的相关网络的状况信息，并将网络状况通过策略响应消息提供 给 hANDSF;
1404、 hANDSF可以根据 UE上报的测量报告， vANDSF提供的或保存在 hANDSF中的相关网络的状态信息以及运营商策略等执行切换决策，为 UE选 择切换的目的网络， 并将决策结果包括发送给 UE, 由 UE根据决策结果执行 后续的切换处理。
需要说明的是， 如果 hANDSF采用存储的网络信息， 则步骤 1402和步骤
1403不需要。
另外， 当 hANDSF收到步骤 1401中 UE发送的消息后， 判断该 UE之前 注册的 vANDSF所在的网络不能为该 UE提供目的网络信息时， 可以根据 UE 当前的位置信息为该 UE选择一个其他网络（其他拜访网络或归属网络） 的 vANDSF， 并向该 vANDSF发送策略请求（如步骤 1402 )， 要求获:^目关接入 网络的信息，此时该新选择的 vANDSF根据 UE的位置信息和策略信息等收集 相关网络的状况， 并通过发送给 hANDSF (如步骤 1403 )。 当 UE需要回归属 网络时， hANDSF也可以直接获取归属网络的其他接入网信息状况， 并完成决 束。
C: 由 vANDSF转为 hANDSF完成切换决策
在由 vANDSF进行切换决策时， 在某些特定情况下可能转由 hANDSF进 行切换决策。 当 vANDSF无法为 UE进行切换决策时， 要求 hANDSF进行切 换决策， 切换决策点改为 hANDSF, 在 hANDSF进行切换决策后， 将决策结 果通过 vANDSF发送给 UE。 由 vANDSF转为 hANDSF完成切换决策具体过程请参阅图 14所示，包括：
1501、 UE向 vANDSF发送测量报告；
1502, hANDSF向 vANDSF转发测量报告 , 该消息中也可以携带当前 UE 的位置信息， 以及运营商的策略信息等；
1503、 vANDSF无法为 UE进行切换决策， 则向 hANDSF发送切换请求 消息，要求 hANDSF进行切换决策，该切换请求消息中可以携带 UE提供的测 量报告；
1504、 hANDSF向 UE发送决策结果；
hANDSF根据 UE当前的位置信息， 根据运营商策略， 选择当前位置其他 网络（其他接入网络或归属网络）的可用接入网资源信息， 并可以通过这些接 入网所在网络的 vANDSF提供相关接入网的状况， 例如负荷状况， 根据 UE 提供的测量报告， 为该 UE执行切换决策， 并将切换决策的结果发送给 UE，由 UE根据该结果执行后续的切换操作。
3 ) 由 UE和 ANDSF共同进行决策
该处理方法和完全由 ANDSF进行决策的流程基本类似， 不同之处在于， 当 UE上报测量报告之前， ANDSF需要先向 UE发送策略信息， 然后 UE根据 该策略信息上报测量报告。 这里所述的 ANDSF 可以是 vANDSF, 也可以是 hANDSF 0 ANDSF—般可以在 UE第一次注册过程中向 UE提供策略信息，或 者当策略信息发生改变后主动向 UE提供。
ANDSF向 UE提供的策略信息一般可以包括： 指定的接入网、 上报的门 限或频率等。 UE根据这些信息对指定网络进行监控， 当相关数据达到上报门 限时， 向 ANDSF上报指定网络的测量报告。 至于 ANDSF的决策处理和完全 由 ANDSF决策下的处理过程是一致的， 此处不再赞述。
本发明实施例二中， UE只需要访问 hANDSF, 就可以通过该 hANDSF获 取由 hANDSF与 vANDSF间利用新增接口进行信息交互后得到的网络状况信 息 , 从而进行相应处理 , 或者获取到由 hANDSF与 vANDSF间利用新增接口 进行信息交互后根据交互结果选择出的目标网络信息，从而能够更简单的实现 网络发现与选择处理。
请参阅图 15， 是本发明实施例三网络架构示意图。 实施例三与实施例一、 实施二的网络结构的主要区别是实施三中 vANDSF和 hANDSF之间没有设置 新接口， 而是利用 PCRF间的接口。
现有技术中提出 ANDSF可以和 PCC ( Policy Control and Charging, 策略 控制和计费） 架构中的 PCRF 功能实体存在接口， 而 PCC 架构中漫游地的 vPCRF和归属地的 hPCRF之间可以通过 S9接口连接， 因此利用此接口也可 以实现 vANDSF和 hANDSF间信息交互， UE可以选择当前网络的 ANDSF , 该 ANDSF通过 vPCRF和 hPCRF获取网络的策略信息和网络状况信息 , 从而 完成切换决策。 ANDSF可以从 PCRF中获取当前 UE的策略信息（如运营商 策略、 UE的业务策略等）， 也可以利用 PCRF的接口从另一个 ANDSF获 目 关信息。
如图 15所示， vANDSF和 hANDSF之间没有直接的交互， UE总是选择 拜访地的 vANDSF,并通过 vPCRF向 hPCRF获取 UE的策略信息。如果 hPCRF 中的策略不足以支持切换决策时， hPCRF也可能向归属地的 hANDSF获取相 关的策略信息。 需要说明的是， 图 15只是以 UE选择 vANDSF为例说明， UE 也可以选择 hANDSF , 并通过 hPCRF和 vPCRF之间的接口连接到 vANDSF。
请参阅图 16， 是本发明实施例三方法流程图， 包括 ：
1701、 UE执行注册流程完成到特定接入网络的注册；
例如可以执行附着流程注册到 3GPP网络、 WiMax网络等。
1702、 UE执行 DNS解析或 DHCP流程向 DNS服务器（ DNS Server )或 DHCP服务器获取 ANDSF 的地址， DNS服务器或 DHCP服务器将配置的
ANDSF的地址返回给 UE;
如果 UE中已经记录所需的 ANDSF的地址，则不需要执行该 DNS解析或 DHCP步骤。
1703、 UE发起到 vANDSF的注册流程， 向 vANDSF请求服务； 该注册流程可以是 UE发起的显式注册，如向 ANDSF发送注册请求消息； 也可以是一个隐式的注册，如 UE向 vANDSF发送策略请求消息或发送周边网 络的测量报告等。
该 vANDSF可以为 UE建立并维护一个上下文。
1704、 vANDSF通过 vPCRF及 hPCRF将 UE注册到 hANDSF; 1705、 UE、 hANDSF, vANDSF, vPCRF及 hPCRF之间进行网络发现与 选择的相关处理。
该实施例中该步骤也可以才 据网络发现与选择决策主体的不同包括三种 情况： 即完全由 UE进行决策、 完全由 ANDSF进行决策、 UE和 ANDSF共同 决策的处理方式。
以 UE进行决策的情况举例说明， 在步骤 1704 完成之后， vANDSF 向 vPCRF请求策略信息 PCRF可以根据该 UE的归属网络信息找到 hPCRF, 并 转发 vANDSF发送的策略请求。 如果 hPCRF没有该 UE的策略信息， 则向 hANDSF发送策略请求， 要求 hANDSF提供相关信息。 hANDSF可以根据 UE 当前的位置信息将归属地设置的策略信息（如该拜访地可用的网络及选择优先 级等）发送给 hPCRF , 则 hPCRF将从 hANDSF处获取的信息通过策略响应消 息发送给 vPCRF, 并进而转发给 vANDSF, 再由 vANDSF将策略信息发送给 UE, 由 UE决定是否需要切换。
对于更伴细举例及其他方式的情况，是和前面所介绍的实施例中的方案原 理是类似， 区别主要在于 ANDSF不直接参与网络选择和发现的处理， 中间需 要 vPCRF及 hPCRF的参与。不过最终决策功能一般是由 ANDSF处理。 当然， 也可以由 PCRF进行处理， 其原理是类似的。 因此， 此处不再详述。
本发明实施例三中， UE只需要访问 vANDSF, 就可以通过该 vANDSF获 取由 vANDSF与 hANDSF间利用现有的 PCRF间接口进行信息交互后得到的 网络状况信息 , 从而进行相应处理 , 或者获取到由 vANDSF与 hANDSF间利 用现有的 PCRF间接口进行信息交互后根据交互结果选择出的目标网络信息 , 从而能够更简单的实现网络发现与选择处理。 明实施例提供一种网络***和装置。
请参阅图 17, 是本发明实施例网络***一结构示意图。
如图 17所示， 网络***包括： 第一接入网发现与选择功能实体 ANDSF 1801、 第二接入网发现与选择功能实体 ANDSF 1802。
第一接入网发现与选择功能实体 ANDSF 1801 , 用于在用户终端接入网络 后，通过与第二 ANDSF 1802的交互获取网络状况信息，将所述网络状况信息 发送给所述用户终端进行目标网络选择，或者 ^居所述网络状况信息为所述用 户终端选择目标网络。
第二接入网发现与选择功能实体 ANDSF 1802, 用于与所述第一 ANDSF 1801进行信息交互。
所述第一 ANDSF 1801具体通过新增的信令接口与所述第二 ANDSF 1802 进行交互获取网络状况信息。
所述第一 ANDSF 1801为拜访地的 vANDSF,所述第二 ANDSF 1802为归 属地的 hANDSF; 或者， 所述第一 ANDSF 1801为归属地的 hANDSF, 所述第 二 ANDSF 1802为拜访地的 vANDSF。
请参阅图 18， 是本发明实施例网络***二结构示意图。
如图 18所示， 网络***包括： 第一接入网发现与选择功能实体 ANDSF 1901、 第二接入网发现与选择功能实体 ANDSF 1902、 归属地策略计费规则功 能实体 hPCRF 1903、 拜访地策略计费规则功能实体 vPCRF 1904。
第一接入网发现与选择功能实体 ANDSF 1901 , 用于在用户终端接入网络 后，通过与第二 ANDSF 1902的交互获取网络状况信息，将所述网络状况信息 发送给所述用户终端进行目标网络选择，或者根据所述网络状况信息为所述用 户终端选择目标网络。
第二接入网发现与选择功能实体 ANDSF 1902, 用于与所述第一 ANDSF 1901进行信息交互。
所述第一 ANDSF 1901 具体通过归属地策略计费规则功能实体 hPCRF
1903 与拜访地策略计费规则功能实体 vPCRF 1904之间的接口与所述第二 ANDSF 1902进行交互获取网络状况信息。
所述第一 ANDSF 1901为拜访地的 vANDSF,所述第二 ANDSF 1902为归 属地的 hANDSF; 或者， 所述第一 ANDSF 1901为归属地的 hANDSF, 所述第 二 ANDSF 1902为拜访地的 vANDSF。 ANDSF与 PCRF的具体连接为： vANDSF 和 vPCRF 1904相连， hANDSF和 hPCRF 1903相连，图 18中第一 ANDSF 1901 与 hPCRF 1903相连只是举例说明。
请参阅图 19, 是本发明实施例通信装置结构示意图。
如图 19所示， 通信装置包括： 交互单元 2002、 处理单元 2003。 这里所述 的通信装置， 可以是接入网发现与选择功能实体 ANDSF。
交互单元 2002， 用于在用户终端接入网络后， 通过与其他的接入网发现 与选择功能实体 ANDSF的交互获取网络状况信息。
处理单元 2003， 用于将所述网络状况信息发送给所述用户终端进行目标 网络选择， 或者根据所述网络状况信息为所述用户终端选择目标网络。
所述交互单元 2002通过新增的接口与所述其他的接入网发现与选择功能 实体 ANDSF进行交互获取网络状况信息； 或者， 所述交互单元 2002是通过 归属地策略计费规则功能实体 hPCRF与拜访地策略计费规则功能实体 vPCRF 之间的接口与所述其他的接入网发现与选择功能实体 ANDSF进行交互获取网 络状况信息。
所述通信装置进一步包括： 判断处理单元 2004。
判断处理单元 2004， 用于接收所述用户终端发送的测量报告后判断出无 法为所述用户终端选择目标网络时，向所述其他的接入网发现与选择功能实体 ANDSF发送消息 , 请求所述 ANDSF为所述用户终端选择目标网络。
所述通信装置进一步包括： 指示单元 2005。
指示单元 2005, 用于向所述用户终端发送策略信息， 指示所述用户终端 根据所述策略信息上报测量报告。
综上所述，上述技术方案可以看出，本发明实施例技术方案中在用户终端 接入网络后， 通过在不同的接入网发现与选择功能实体 ANDSF间交互获取网 络状况信息， 因此用户终端只需要访问其中一个 ANDSF, 就可以通过该
ANDSF获取网络侧进行信息交互后得到的网络状况信息，从而进行相应处理， 或者获取到网络侧进行信息交互后根据交互结果选择出的目标网络信息，从而 能够更简单的实现网络发现与选择处理。
进一步的， 本发明实施例技术方案中， 所述第一 ANDSF可以通过新增的 接口与所述第二 ANDSF进行交互获取网络状况信息；或者，所述第一 ANDSF 可以通过归属地策略计费规则功能实体 hPCRF与拜访地策略计费规则功能实 体 vPCRF之间的接口与所述第二 ANDSF进行交互获取网络状况信息。
进一步的， 本发明实施例技术方案可以是用户终端访问拜访地的 vANDSF , 也可以是访问归属地的 hANDSF。 以上对本发明实施例所提供的一种网络发现与选择方法、网络***及通信 装置进行了详细介绍 ,对于本领域的一般技术人员 ,依据本发明实施例的思想 , 在具体实施方式及应用范围上均会有改变之处， 综上所述，本说明书内容不应 理解为对本发明的限制。

Claims

权 利 要 求
1、 一种网络发现与选择方法， 其特征在于， 包括：
在用户终端接入网络后，
第一接入网发现与选择功能实体 ANDSF通过与第二 ANDSF的交互获取 网络状况信息；
所述第一 ANDSF将所述获取的网络状况信息发送给所述用户终端进行目 标网络选择， 或者根据所述获取的网络状况信息为所述用户终端选择目标网 络。
2、 根据权利要求 1所述的网络发现与选择方法， 其特征在于：
所述第一 ANDSF通过与第二 ANDSF的交互获取网络状况信息包括： 所述第一 ANDSF通过新增的接口与所述第二 ANDSF进行交互获取网络 状况信息； 或者，
所述第一 ANDSF通过归属地策略计费规则功能实体 hPCRF与拜访地策 略计费规则功能实体 vPCRF之间的接口， 与所述第二 ANDSF进行交互获取 网络状况信息。
3、 根据权利要求 2所述的网络发现与选择方法， 其特征在于：
所述第一 ANDSF通过与第二 ANDSF的交互获取网络状况信息之前进一 步包括：
所述第一 ANDSF接收用户终端的注册消息进行注册， 并将所述注册消息 直接发送或通过 vPCRF及 hPCRF发送到所述第二 ANDSF进行注册。
4、根据权利要求 1至 3任一项所述的网络发现与选择方法，其特征在于： 所述第一 ANDSF为拜访地的 vANDSF, 所述第二 ANDSF 为归属地的 hANDSF, 所述第一 ANDSF通过与第二 ANDSF的交互获取网络状况信息包 括：
所述 vANDSF接收所述用户终端发送的测量报告后， 向所述 hANDSF发 送请求， 所述测量报告由所述用户终端主动发出或者是在接收所述 vANDSF 下发的策略信息后根据所述策略信息发出；
接收所述 hANDSF根据所述请求返回的策略信息；
根据所述接收的策略信息收集网络状况信息。
5、根据权利要求 1至 3任一项所述的网络发现与选择方法，其特征在于： 所述第一 ANDSF为 vANDSF, 所述第二 ANDSF为 hANDSF, 所述第一
ANDSF通过与第二 ANDSF的交互获取网络状况信息包括：
所述 vANDSF 接收 hANDSF 发送的策略信息， 所述策略信息是所述 hANDSF接收所述用户终端发送的测量报告后获取，所述测量报告由所述用户 终端主动发出或者是在接收所述 vANDSF下发的策略信息后根据所述策略信 息发出；
根据所述接收的策略信息收集网络状况信息。
6、根据权利要求 1至 3任一项所述的网络发现与选择方法，其特征在于： 所述第一 ANDSF为 hANDSF, 所述第二 ANDSF为 vANDSF, 所述第一
ANDSF通过与第二 ANDSF的交互获取网络状况信息包括：
所述 hANDSF接收 vANDSF发送的网络状况信息 , 所述网络状况信息是 所述 vANDSF接收所述用户终端发送的测量报告后收集得到 ,
所述测量报告由所述用户终端主动发出或者是在接收所述 hANDSF下发 的策略信息后根据所述策略信息发出。
7、根据权利要求 1至 3任一项所述的网络发现与选择方法，其特征在于： 所述第一 ANDSF为 hANDSF, 所述第二 ANDSF为 vANDSF, 所述第一
ANDSF通过与第二 ANDSF的交互获取网络状况信息包括：
所述 hANDSF接收所述用户终端发送的测量报告后向所述 vANDSF发送 请求， 所述测量报告由所述用户终端主动发出或者是在接收所述 hANDSF下 发的策略信息后根据所述策略信息发出；
接收所述 vANDSF根据所述请求返回的网络状况信息。
8、根据权利要求 1至 3任一项所述的网络发现与选择方法，其特征在于： 所述第一 ANDSF为 hANDSF, 所述第二 ANDSF为 vANDSF,
所述第一 ANDSF通过与第二 ANDSF的交互获取网络状况信息包括： 所述 hANDSF 接收所述 vANDSF 的切换请求， 所述切换请求是所述 vANDSF接收所述用户终端发送的测量4艮告并判断出无法为所述用户终端选 择目标网络后发出；
所述 hANDSF接收所述切换请求后 , 收集网络状况信息。
9、根据权利要求 1至 3任一项所述的网络发现与选择方法，其特征在于： 所述第一 ANDSF通过与第二 ANDSF的交互获取网络状况信息之前进一 步包括：
接收所述用户终端发送的策略请求消息；
所述第一 ANDSF将所述网络状况信息发送给所述用户终端进行目标网络 选择。
10、 一种网络***， 其特征在于， 包括：
第一接入网发现与选择功能实体 ANDSF , 用于在用户终端接入网络后 , 通过与第二 ANDSF的交互获取网络状况信息， 将所述网络状况信息发送给所 述用户终端进行目标网络选择，或者 ^居所述网络状况信息为所述用户终端选 择目标网络；
第二接入网发现与选择功能实体 ANDSF, 用于与所述第一 ANDSF进行 信息交互。
11、 根据权利要求 10所述的网络***， 其特征在于：
所述第一 ANDSF通过新增的信令接口与所述第二 ANDSF进行交互获取 网络状况信息。
12、 根据权利要求 10所述的网络***， 其特征在于：
所述网络***进一步包括归属地策略计费规则功能实体 hPCRF和拜访地 策略计费规则功能实体 vPCRF;
所述第一 ANDSF通过归属地策略计费规则功能实体 hPCRF与拜访地策 略计费规则功能实体 vPCRF之间的接口， 与所述第二 ANDSF进行交互获取 网络状况信息。
13、 根据权利要求 10至 12任一项所述的网络***， 其特征在于： 所述第一 ANDSF 为拜访地的 vANDSF, 所述第二 ANDSF 为归属地的 hANDSF; 或者，
所述第一 ANDSF 为归属地的 hANDSF, 所述第二 ANDSF 为拜访地的 vANDSF0
14、 一种通信装置， 其特征在于， 包括：
交互单元， 用于在用户终端接入网络后，通过与其他的接入网发现与选择 功能实体 ANDSF的交互获取网络状况信息；
处理单元，用于将所述网络状况信息发送给所述用户终端进行目标网络选 择， 或者根据所述网络状况信息为所述用户终端选择目标网络。
15、 根据权利要求 14所述的通信装置， 其特征在于：
ANDSF进行交互获取网络状况信息； 或者，
所述交互单元通过归属地策略计费规则功能实体 hPCRF与拜访地策略计 费规则功能实体 vPCRF之间的接口， 与所述其他的接入网发现与选择功能实 体 ANDSF进行交互获取网络状况信息。
16、根据权利要求 14或 15所述的通信装置， 其特征在于， 所述通信装置 进一步包括：
判断处理单元，用于接收所述用户终端发送的测量报告并判断出无法为所 述用户终端选择目标网络时， 向所述其他的接入网发现与选择功能实体 ANDSF发送消息 , 请求所述 ANDSF为所述用户终端选择目标网络。
17、 根据权利要求 16所述的通信装置， 其特征在于， 所述通信装置进一 步包括：
指示单元， 用于向所述用户终端发送策略信息， 指示所述用户终端根据所 述策略信息上报测量报告。
PCT/CN2009/070741 2008-03-18 2009-03-11 网络发现与选择方法、网络***及通信装置 WO2009115015A1 (zh)

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