8.44 Enhanced Relocation Complete

25.4133GPPRelease 17TSUTRAN Iu interface Radio Access Network Application Part (RANAP) signalling

8.44.1 General

The purpose of the Enhanced Relocation Complete procedure is to inform the CN that the resources have been allocated by the target RNC. The target RNC provides necessary information to the CN to switch the user plane to the target RNC.

The procedure uses connection oriented signalling.

8.44.2 Successful Operation

Figure 58: Enhanced Relocation Complete procedure. Successful operation.

The RNC initiates the procedure by sending the ENHANCED RELOCATION COMPLETE REQUEST message to the CN.

If the RABs Setup List IE in the ENHANCED RELOCATION COMPLETE REQUEST message does not include all RABs previously established for the UE, the CN shall consider the non included RABs as implicitly released by the RNC.

For each RAB the resource allocation was successful towards the PS domain or towards the CS domain when an ALCAP is not used, the RNC shall include the Transport Layer Address IE and the Iu Transport Association IE in the RABs Setup List IE in the ENHANCED RELOCATION COMPLETE REQUEST message. If any alternative RAB parameter values have been used when allocating the resources, these RAB parameter values shall be included in the ENHANCED RELOCATION COMPLETE REQUEST message within the Assigned RAB Parameter Values IE.

NOTE: If ALCAP is not used, the RNC shall include the same kind of TNL information (i.e. IPv4 or IPv6) as received from the source RNC in the RANAP ENHANCED RELOCATION INFORMATION REQUEST message.

The target RNC shall include the Chosen Integrity Protection Algorithm IE (Chosen Encryption Algorithm IE respectively) within the ENHANCED RELOCATION COMPLETE REQUEST message, if, and only if the Integrity Protection Key IE (Ciphering Key IE respectively) was included within the Source RNC To Target RNC Transparent Container IE of the RANAP ENHANCED RELOCATION INFORMATION message.

If the Higher bitrates than 16 Mbps flag IE is included in the ENHANCED RELOCATION COMPLETE REQUEST message then the CN shall, if supported, use the IE as described in TS 23.060 [21].

If the CSG Id IE and the Cell Access Mode IE set to "hybrid" are received in the ENHANCED RELOCATION COMPLETE REQUEST message, the CN shall provide the CSG Membership Status IE of the UE to the target side.

After all necessary updates including the DL transport layer information have been successfully completed in the CN, the CN shall send the ENHANCED RELOCATION COMPLETE RESPONSE message to the RNC.

In case the CN failed to setup for at least one of the RABs included the RABs Setup List IE in the ENHANCED RELOCATION COMPLETE REQUEST message, the CN shall include the RABs it failed to setup in the RABs To Be Released List IE in the ENHANCED RELOCATION COMPLETE RESPONSE message. In this case, the RNC shall release the resource for the RABs and the RNC shall regard the RABs indicated in the RABs To Be Released List IE as being fully released.

The ENHANCED RELOCATION COMPLETE RESPONSE message shall contain the User Plane Information IE.

The ENHANCED RELOCATION COMPLETE RESPONSE message shall contain the Transport Layer Address IE and the Binding ID IE for each RAB towards the CS domain when an ALCAP is used.

In case the CN decides to change the uplink transport layer information when an ALCAP is not used it may include the Transport Layer Address IE and the Binding ID IE within the RABs Setup List IE in the ENHANCED RELOCATION COMPLETE RESPONSE message.

The ENHANCED RELOCATION COMPLETE RESPONSE message may contain the RAB Parameters IE for each RAB towards the CS domain in RAB Setup List.

If the RAB Parameters IE is included in the ENHANCED RELOCATION COMPLETE RESPONSE the RNC shall

– replace the previously provided RAB Parameter for the RAB. The RNC shall use the received RAB Parameter for the RAB.

If the RAB Parameters IE is not contained in the ENHANCED RELOCATION COMPLETE RESPONSE message, the RNC shall use the previously provided RAB parameters.

The ENHANCED RELOCATION COMPLETE RESPONSE message may contain the UE Aggregate Maximum Bit Rate IE to control the aggregate data rate of non-GBR traffic for this UE.

If the UE Aggregate Maximum Bit Rate IE is contained in the ENHANCED RELOCATION COMPLETE RESPONSE message, the RNC shall, if supported,

– replace the previously provided UE Aggregate Maximum Bit Rate Parameter for this UE. The RNC shall use the received UE Aggregate Maximum Bit Rate Parameter for this UE.

If the UE Aggregate Maximum Bit Rate IE is not contained in the ENHANCED RELOCATION COMPLETE RESPONSE message, the RNC shall, if supported, use the previously provided UE Aggregate Maximum Bit Rate Parameter.

In case SIPTO at Iu-PS functionality is supported by the UTRAN, the following applies in addition for the successful operation of Enhanced Relocation Complete procedure:

– If the MSISDN IE is present in the ENHANCED RELOCATION COMPLETE RESPONSE message, then the UTRAN may offload the RAB(s) where the Offload RAB Parameters IE is present in the RABs Setup Item IEs IE. The Access Point Name IE and the Charging Characteristics IE within the Offload RAB Parameters IE and the MSIDSN IE may only be used for the SIPTO at Iu-PS function and according to the description in TS 23.060 [21].

If the CSG Membership Status IE is included in the ENHANCED RELOCATION COMPLETE RESPONSE message the RAN shall, if supported, take the following:

– If the cell that serves the UE is a Hybrid cell, the RNC shall store the value contained in the CSG Membership Status IE and replace any previously stored membership status value by this new one. The RNC may use such information to perform differentiated treatment for member and non-member UEs.

If the Tunnel Information for BBF IE is received in the ENHANCED RELOCATION COMPLETE REQUEST message, the CN shall, if supported, use the IE as described in TS 23.139 [65].

If the LHN ID IE is included in the ENHANCED RELOCATION COMPLETE REQUEST message, the CN shall, if supported, use it as specified in TS 23.060 [21].

8.44.3 Unsuccessful Operation

Figure 59: Enhanced Relocation Complete procedure. Unsuccessful operation.

If a failure occurs in the CN during the execution of the relocation procedure, the CN shall send the ENHANCED RELOCATION COMPLETE FAILURE message to the RNC with an appropriate cause value. The RNC shall assume the Iu resources between the old source RNC and the CN node being released by the respective CN node.