9.3 Procedures for Fixed Broadband Access network using HNB for PS services

23.1393GPP3GPP system - fixed broadband access network interworkingRelease 17Stage 2TS

9.3.1 PDP Context Activation

The HNB is already registered in the network. The HNB GW sends the HNB local IP address and the UDP port number if NAT/NAPT is detected to the SGSN in the [RANAP] INITIAL UE MESSAGE message (for the message refer to TS 25.413 [28]).

Depicted in Figure 9.3.1-1 is the PDP Context Activation procedure.

Figure 9.3.1-1: PDP Context Activation Procedure for EPS-connected 3G access

0. The HNB connected. The HNB GW received the HNB Local IP address and the UDP port number if NAT/NAPT is detected.

1. This step is the same as step 1 in TS 23.060 [22] clause 9.2.2.1, with the addition that the HNB GW includes in the [RANAP] INITIAL UE MESSAGE message the HNB Local IP address and the UDP port number if NAT/NAPT is detected.

2. This step is the same as step A in TS 23.060 [22] clause 9.2.2.1A, with the addition that the S4-SGSN also includes HNB Local IP address and the UDP port number if NAT/NAPT is detected in the Create Session Request sent to the S-GW and in turn to P-GW.

3. The P-GW sends the IP-CAN session establishment request to the PCRF according to TS 23.203 [4]. The message includes HNB Local IP address and the UDP port number if NAT/NAPT is detected.

4. The PCRF sends the Gateway Control Session establishment message to the BPCF according to TS 23.203 [4]. The message includes the IMSI, HNB local IP address, the UDP port number if NAT/NAPT is detected.

Once this step completes the PCRF is aware the fact that the UE is connected to the network via a 3GPP H(e)NB and checks first whether sufficient resources are available in the BBF access before it provisions PCC rules at the P-GW.

5. The PCRF acknowledges the IP-CAN session establishment ack to the P-GW.

6. This step is the same as step D in TS 23.060 [22] clause 9.2.2.1A Figure 64a with the following additions. If the local H(e)NB IP address and UDP port number information change reporting triggers are received from the PCRF, the PDN GW should set the H(e)NB local IP address and UDP port number reporting accordingly. If the H(e)NB local IP address and UDP port number Reporting Request is received for this PDP context, then the SGSN shall report to the PCEF/PCRF changes of HNB local IP address and/or port (if available).

7-8. Steps 7 and 8 are the same as steps 4-9 in TS 23.060 [22] clause 9.2.2.1 Figure 64.

Editor’s note: In order to handle mobility from macro cells, the tunnel information needs to be added in other RANAP messages (RELOCATION COMPLETE and INITIAL UE MESSAGE).

9.3.2 Secondary PDP Context Activation and PDP Context Modification Procedure

This procedure is executed when secondary PDP context is activated and QoS needs to be allocated to it or when PDP context/bearer is modified and its QoS needs to be updated. This clause contains the following cases:

– Secondary PDP Context Activation Procedure, PDP Creation part, using S4 (TS 23.060 [22], clause 9.2.2.1.1A).

– Network Requested Secondary PDP Context Activation Procedure using S4 (TS 23.060 [22], clause 9.2.2.3A).

– SGSN-Initiated EPS Bearer Modification Procedure using S4 (TS 23.060 [22], clause 9.2.3.1A and clause 9.2.3.1B).

– P-GW Initiated EPS Bearer Modification Procedure, using S4 (TS 23.060 [22], clause 9.2.3.2A).

– UE-Initiated EPS Bearer Modification Procedure using S4 (TS 23.060 [22], clause 9.2.3.3A , clause 9.2.3.3B and clause 9.2.3.3C).

Depicted in Figure 9.3.2-1 is the corresponding procedure. It only shows the changed steps, and the steps without change can be referred to the corresponding clauses in TS 23.060 [22].

Figure 9.3.2-1: Secondary PDP context Activation or PDP Context Modification Procedure for EPS-connected 3G access

1. This step is the same as the corresponding procedure in TS 23.060 [22].

For UE-Initiated secondary PDP context activation procedure, refer to steps A and B in TS 23.060 [22], clause 9.2.2.1.1A. For UE-Initiated bearer modification procedure, refer to clause 9.2.3.3A, Figure 72c. For SGSN-Initiated bearer modification procedure, refer to steps A and B in clause 9.2.3.1A, Figure 70c. For all cases, the P-GW sends a QoS authorization request to the PCRF.

2. The PCRF initiates Gateway control and QoS rule provision procedure with the BPCF in order to update the resources allocation in the BBF access network as per TS 23.203 [4], Annex P.7.4.1.

3. IP-CAN session modification procedure is performed by the PCRF to provide PCC rule(s) to the P-GW.

4. The execution and response part of UE-Initiated secondary PDP context activation are the same as steps C to F in TS 23.060 [22], clause 9.2.2.1.1A. For network requested secondary PDP context activation, refer to clause 9.2.2.3A. For UE-Initiated bearer modification procedure, refer to clause 9.2.3.3B and clause 9.2.3.3C. For SGSN-Initiated bearer modification procedure, refer to steps C and D in clause 9.2.3.1A. For P-GW or PCRF-Initiated bearer modification procedure, refer to clause 9.2.3.2A.

9.3.3 Detach, PDP Context and EPS-Bearer Deactivation Procedures

This procedure is executed when the PDP context or EPS-bearer is released. This clause contains the following cases:

– SGSN interaction during Detach Procedure when using S4 (clause 6.6.3, TS 23.060 [22])

– UE and SGSN Initiated PDN connection Deactivation Procedure using S4 (clause 9.2.4.1A.1, TS 23.060 [22])

– UE and SGSN Initiated Bearer Deactivation Procedure (clause 9.2.4.1A.2, TS 23.060 [22])

– P-GW initiated Bearer Deactivation Procedure using S4 (clause 9.2.4.3A and clause 9.2.4.3B, TS 23.060 [22])

Depicted in Figure 9.3.4-1 is the Detach or PDP Context/Bearer Deactivation procedure. It only shows the changed steps, and the steps without change can be referred to the corresponding clauses in TS 23.060 [22].

Figure 9.3.3-1: PDP Context/Bearer Deactivation Procedure for EPS-connected 3G access

1. This step is the same as the corresponding procedure in TS 23.060 [22]. (For Detach procedure, refer to steps A and B in clause 6.6.3; For UE or SGSN initiated PDN connection deactivation, refer to steps A and B in clause 9.2.4.1A.1; For UE or SGSN initiated bearer deactivation, refer to steps A and B in clause 9.2.4.1A.2).

2. For the UE detaches from the network or the PDN connection deactivation case, the P-GW initiates IP-CAN session termination with the PCRF. Otherwise, the P-GW initiates IP-CAN session modification with the PCRF.

3. The PCRF initiates the Gateway Control and QoS Rule provision procedure or the Gateway control session termination with the BPCF in order to release resources in the BBF access network as per Annex P.7.4.1, TS 23.203 [4].

4. This step can refer to the corresponding procedure as in TS 23.060 [22]. For Detach procedure, refer to Steps C and D in clause 6.6.3. For UE or SGSN initiated bearer deactivation, refer to Steps C to F in clause 9.2.4.1A.2. For UE or SGSN initiated PDN connection deactivation, refer to Steps C and D in clause 9.2.4.1A.1. For P-GW or PCRF initiated bearer deactivation, refer to clause 9.2.4.3A and clause 9.2.4.3B.

9.3.4 Service Request and Handover Procedures

This clause specifies the Service Request and Handover Procedures with updating the following information to fixed broadband access network: the HNB local IP address and the UDP port if NAT/NAPT is detected.

This clause contains the following cases:

– Inter SGSN Routeing Area Update and Combined Inter SGSN RA / LA Update using S4 (TS 23.060 [22], clause 6.9.1.2.2a).

– Routeing Area Update Procedure using S4 (TS 23.060 [22], clause 6.9.2.1a).

– Serving RNS Relocation Procedure, Combined Hard Handover and SRNS Relocation Procedure, and Combined Cell / URA Update and SRNS Relocation Procedure Using S4 (TS 23.060 [22], clause 6.9.2.2.1a).

– Enhanced Serving RNS Relocation Procedure using S4(TS 23.060 [22], clause 6.9.2.2.5a).

– UE Initiated Service Request Procedure Using S4(TS 23.060 [22], clause 6.12.1A).

– Iu mode to A/Gb mode Intra SGSN Change using S4(TS 23.060 [22], clause 6.13.1.1.2).

– A/Gb mode to Iu mode Intra-SGSN Change using S4 (TS 23.060 [22], clause 6.13.1.2.2).

– Iu mode to A/Gb mode Inter-SGSN Change using S4 (TS 23.060 [22], clause 6.13.2.1.2).

– A/Gb mode to Iu mode Inter-SGSN Change using S4 (TS 23.060 [22], clause 6.13.2.2.2).

Depicted in Figure 9.3.5-1 is the service request or handover procedure. It only shows the changed steps, and the steps without change can be referred to the corresponding clauses in TS 23.060 [22].

Figure 9.3.4-1: Service Request and Handover Procedures for EPS-connected 3G access

1. UE initiated Service request procedure or Handover procedure, which can be referred to the descriptions of the corresponding clause in TS 23.060 [22], with the addition that target HNB sends the target HNB local IP address and the UDP port if NAT/NAPT is detected to the target SGSN in the [RANAP] RELOCATION COMPLETE message or ENHANCED RELOCATION COMPLETE REQUEST message (for the messages refer to TS 25.413 [28]).

2. Step 2a and 2b are the same as that in TS 23.060 [22]:

2a. If there is a change in S-GW, the target SGSN sends the Create session request message to the target S-GW. If the S-GW is not changed, the (target) SGSN sends the modify bearer request message to the S-GW. The following information may be included: target HNB Local IP address and the UDP port if NAT/NAPT is detected.

2b. The (target) S-GW sends the modify bearer request message to the P-GW, based on conditions specified in TS 23.401 [2] (e.g. the S-GW is changed) or if the following information is received in step 2a: target HNB Local IP address and the UDP port if NAT/NAPT is detected.

3. The P-GW sends IP-CAN session modification request message to the PCRF including the Target HNB local IP address and the UDP port if NAT/NAPT is detected as defined in TS 23.203 [4], Annex P.7.4.1.

If the Modify bearer Request message received by P-GW in step 3 contains none of the additional information: HNB Local IP address and the UDP port if NAT/NAPT is detected., the P-GW determines that the UE leaves the H(e)NB and will inform this event to PCRF.

4. If the UE moves from macro NB to a HNB, or the PCRF will initiate PCRF-initiated Gateway control session establishment procedure as defined in TS 23.203 [4] if the UE is the first UE attaching the target HNB; if the UE moves from one HNB to another HNB without fixed network backhaul changed or if the UE moves to a new HNB and there has been one Gateway Control Session for that HNB, the PCRF will initiate Gateway control and QoS rule provisioning procedure with BPCF as defined in TS 23.203 [4]. The HNB local IP address, the UDP port if NAT/NAPT is detected, shall be included in the PCRF-Initiated Gateway control session establishment procedure and in Gateway Control and QoS rule provisioning procedure.

5. The PCRF acknowledges the IP‑CAN session modification.

6. If UE moves from one HNB to macro cell, the PCRF will terminate the old Gateway control session if this is the last UE under the source HNB; if the UE moves from macro NB to a HNB, or the UE moves from one HNB to another HNB without fixed network backhaul changed, or there are other UEs attached the source HNB, this step will be skipped.

7. This step can refer to the corresponding procedure as in TS 23.060 [22].

NOTE: The interaction between the BPCF and the BNG is out of scope.