5.6 Container handling

3GPP43.129Packet-switched handover for GERAN A/Gb modeRelease 17Stage 2TS

There are two transparent containers defined for the PS handover in GERAN A/Gb mode and GAN mode:

– Source BSS to Target BSS Transparent Container.

– Target BSS to Source BSS Transparent Container.

The Source BSS to Target BSS Transparent Container will carry the information to be transported transparently between the source BSS and the target BSS/GANC and between the source GANC and the target BSS related to PS handover.

The Target BSS to Source BSS Transparent Container will carry the information to be transported transparently between the target BSS and the source BSS/GANC and between the target GANC and the source BSS related to PS handover.

The generic handling of the source cell (GERAN A/Gb mode or UTRAN/GERAN Iu mode or E-UTRAN) to target cell (GERAN A/Gb mode or UTRAN/GERAN Iu mode or E-UTRAN) radio-related container is as follows:

– Created by the source BSS or RNC or eNB .

– Processed by the target BSS or RNC or eNB.

– Forwarded transparently by the SGSNs and MME .

The generic handling of the target cell (GERAN A/Gb mode or UTRAN/GERAN Iu mode or E-UTRAN ) to source cell (GERAN A/Gb mode or UTRAN/GERAN Iu mode or E-UTRAN) radio-related container is as follows:

– Created by the target BSS or RNC or eNB.

– Processed by the source BSS or RNC or eNB .

– Forwarded transparently by the SGSNs and MME .

The generic handling of the source cell to target cell radio-related container for PS handover from GERAN A/Gb mode to GAN mode or vice versa is as follows:

– Created by the source BSS or GANC.

– Processed by the target BSS for PS handover from a source GANC.

– Processed by the target GANC for PS handover from a source BSS.

– Forwarded transparently by the SGSNs.

The generic handling of the source cell to target cell radio-related container for PS handover from UTRAN to GAN mode or vice versa is as follows:

– Created by the source GANC or RNC.

– Processed by the target GANC for PS handover from a source RNC.

– Processed by the target RNC for PS handover from a source GANC.

– Forwarded transparently by the SGSNs.

The generic handling of the target cell to source cell radio-related container for PS handover from GERAN A/Gb mode to GAN mode or vice versa is as follows:

– Created by the target GANC or BSS.

– Processed by the source BSS for PS handover to a target GANC.

– Processed by the source GANC for PS handover to a target BSS.

– Forwarded transparently by the SGSNs.

The generic handling of the target cell to source cell radio-related container for PS handover from UTRAN to GAN mode or vice versa is as follows:

– Created by the target GANC or RNC.

– Processed by the source RNC for PS handover to a target GANC.

– Processed by the source GANC for PS handover to a target RNC.

– Forwarded transparently by the SGSNs.

5.6.1 Contents of the containers

The transparent container will consist of two parts:

– The Radio Network part (RN part) carrying radio interface related parameters relevant for the MS and the radio network (BSS/RNC/eNB ) and sent transparently through the core network; This content is:

– Created by the source BSS/RNC/GANC/eNB and carried in the Source BSS to Target BSS / Source to Target transparent container (i.e. the forward container).

– Created by the target BSS/RNC/GANC/eNB and carried in the Target BSS to Source BSS / Target to Source transparent container (i.e. the reverse container).

– Processed by the target BSS/RNC/GANC/eNB (forward container only)

– Processed by the source BSS/RNC/GANC/eNB and MS (reverse container only).

– The Core Network part (CN part) carrying parameters relevant for the MS and the core network. This part is only needed from the new SGSN to send to the MS for PS handover to A/Gb mode and GAN mode and thus is only included in the Target BSS to Source BSS Transparent Container. This content is:

– Created by the new SGSN.

– Included in the Target BSS to Source BSS Transparent Container by the target BSS/GANC.

NOTE 1: The target BSS/GANC does not process the Core Network part.

– Forwarded transparently by the old SGSN and source BSS/RNC/GANC/eNB.

– Carried within the PS Handover Command message sent from the source BSS to the MS for PS handover from A/Gb mode to A/Gb mode or for PS handover from A/Gb mode to GAN mode.

– Carried within the PS Handover Command message included within a GA-PSR Handover Command message sent from the source GANC to the MS for PS handover from GAN mode to A/Gb mode.

– Carried within the PS Handover Command message included within a Handover from UTRAN Command message or the Handover from GERAN Iu Command message sent from the source RNC to the MS for PS handover from Iu mode to A/Gb mode.

– Carried within the PS Handover Command message included within a Handover from UTRAN Command message sent from the source RNC to the MS for PS handover from UTRAN to GAN mode.

– Carried within the PS Handover Command message included within a MobilityFromEUTRACommand message sent from the source eNB to the MS for PS handover from E-UTRAN to GERAN A/Gb mode.

– Processed by the MS.

The contents of the Radio Network part will depend on:

– Type of channels that are subject to PS handover, i.e. shared or dedicated.

NOTE 2: Currently dedicated channels are not considered in the PS handover in GERAN A/Gb mode.

– PS handover scenario, i.e. intra-mode or inter-RAT/mode.

– Whether it is sent in a forward container or a reverse container.

The contents of the Core Network part will depend on the PS handover scenario, i.e. intra-mode or inter-RAT/mode.

5.6.1.1 Contents of the GERAN A/Gb mode or GAN mode → GERAN A/Gb mode Transparent Containers

5.6.1.1.1 Source BSS to Target BSS Transparent Container

In GERAN A/Gb mode/GAN mode -> GERAN A/Gb mode the Source BSS to Target BSS Transparent Container is sent in the PS Handover Required message, the Forward Relocation Request message and the PS Handover Request message.

The Radio Network part consists of the following:

– MS RAC.

– Inter RAT handover Info (defined in 3GPP TS 25.331) containing the START_PS and UE RAC values, if available.

– E-UTRAN INTER RAT HANDOVER INFO (defined in 3GPP TS 48.018, see also 3GPP TS 36.331) if available

NOTE 1: The START_PS and UE RAC are needed to support PS Handover to UTRAN/GERAN Iu mode.

NOTE 2: The way of transferring START_PS and UE RAC from the mobile station to the BSS/GANC, is to piggyback the RRC container INTER RAT HANDOVER INFO, which includes START_PS and UE RAC, to the Attach Complete and Routing Area Update Complete messages from the mobile station to the SGSN. The SGSN will then include this container in every CREATE-BSS-PFC message sent to the BSS/GANC and/or in the PS Handover Complete Acknowledge message.

5.6.1.1.2 Target BSS to Source BSS Transparent Container

In GERAN A/Gb mode/GAN mode -> GERAN A/Gb mode the Target BSS to Source BSS Transparent Container is sent in the PS Handover Request Acknowledge message, Forward Relocation Response message and the PS Handover Required Acknowledge message.

The Radio Network part consists of the required information for access in the target cell and the information on allocated radio resources, uplink and downlink TBF parameters, Handover reference and generic parameters for access in the target cell (i.e. GPRS cell options, target cell "Cell Selection struct", global power control parameters, reference frequency lists, cell allocation, GPRS mobile allocation).

The Core Network part (i.e. NAS Container for PS HO) consists of the following parameters:

– an XID Command indicating Reset or ‘Reset to old XID parameters’ and the new IOV-UI for the target cell;

– the GPRS ciphering algorithm to be used in the target cell, if it is different from the ciphering algorithm used in the source cell.

5.6.1.2 Contents of the GERAN A/Gb mode or GAN mode → UTRAN Transparent Containers

5.6.1.2.1 Source to Target Transparent Container

In GERAN A/Gb mode/GAN mode -> UTRAN the Source to Target Transparent Container is encoded as the Source RNC to Target RNC Transaprent Container. It is sent from the source BSS/GANC to the target RNC in the PS Handover Required message and the Relocation Request message.

The Radio Network part consists of the following:

– RRC Container as defined in 3GPP TS 25.331 [17] will contain Inter RAT Handover Info (UTRAN specific information including START_PS/UE RAC) and Inter RAT UE radio access capability including MS RAC from BSS to RNC.

– Target Cell Id.

– Number of Iu instances IE. The value of this IE is set to 1 as defined in 3GPP TS 25.413 [23].

– Relocation Type. The value of the IE is set to "UE involved", as defined in 3GPP TS 25.413 [23].

5.6.1.2.2 Target to Source Transparent Container

In GERAN A/Gb mode/GAN mode -> UTRAN the Target to Source Transparent Container is encoded as the Target RNC to Source RNC Transparent Container. Itis sent from the target RNC to the source BSS/GANC in the Relocation Request Acknowledge message, Forward Relocation Response message and the PS Handover Required Acknowledge message.

The Radio Network part consists of the RRC message, i.e. the Handover to UTRAN Command message (as defined in 3GPP TS 25.331 [17]) used to perform handover from GERAN A/Gb mode/GAN mode to UTRAN. This message will be sent to the MS/UE within the PS Handover Command message (for PS handover from GERAN A/Gb mode) or within the GA-PSR Handover Command message (for PS handover from GAN mode).

5.6.1.3 Contents of the UTRAN → GERAN A/Gb Mode or GAN mode Transparent Containers

5.6.1.3.1 Source BSS to Target BSS Transparent Container

In UTRAN -> GERAN A/Gb mode/GAN mode the Source BSS to Target BSS Transparent Container is sent from the source RNC to the target BSS/GANC in the Relocation Required, Forward Relocation Request message and the PS Handover Request message in order to support inter-RAT PS handover from UTRAN (CELL_DCH state or CELL_FACH state, only PS RABs established) to GERAN A/Gb mode/GAN mode.

The Radio Network part consists of the following information:

– MS RAC.

– Inter RAT handover Info (defined in 3GPP TS 25.331) containing the START_PS and UE RAC values.

– E-UTRAN INTER RAT HANDOVER INFO (defined in 3GPP TS 48.018, see also 3GPP TS 36.331) if available

NOTE: The START_PS value received in the INTER RAT HANDOVER INFO is not always aligned with the START_PS value stored in the MS after it has attached to the GSM network. The target BSS shall replace the value received in the container received from the source RNC with the value received from the MS via the SGSN (i.e. within a CREATE-BSS-PFC message or a PS Handover Complete Acknowledge message).

5.6.1.3.2 Target BSS to Source BSS Transparent Container

In UTRAN -> GERAN A/Gb mode/GAN mode the Target BSS to Source BSS Transparent Container is sent from the target BSS/GANC to the source RNC in the PS Handover Request Acknowledge message, Forward Relocation Response message and the Relocation Command message in order to support inter-RAT PS handover from UTRAN (CELL_DCH state or CELL_FACH state, only PS RABs established) to GERAN A/Gb mode/GAN mode.

For PS handover from UTRAN to GERAN A/Gb mode the Radio Network part consist of the required information for access in the target cell and the information on allocated radio resources: uplink and downlink TBF parameters, PS Handover reference and generic parameters for access in the target cell (i.e. GPRS cell options, target cell "Cell Selection struct", global power control parameters, reference frequency lists, cell allocation, GPRS mobile allocation). Over the air interface this radio network container is sent within the Handover from UTRAN Command message.

For PS handover from UTRAN to GAN mode the Radio Network part consists only of the mandatory fields within the PS Handover Radio Resources IE carried within the PS Handover Command message.

The Core Network part (i.e. NAS Container for PS HO) consist of the following parameters:

– an XID Command indicating Reset or ‘Reset to old XID parameters’ and the new IOV-UI for the target cell;

– the GPRS ciphering algorithm to be used in the target cell;

5.6.1.4 Contents of the GERAN A/Gb mode → GERAN Iu mode Transparent Containers

5.6.1.4.1 Source to Target Transparent Container

In GERAN A/Gb mode -> GERAN Iu mode the Source to Target Transparent Container is encoded as the Source RNC to Target RNC Transparent Container. It is is sent from the source BSS to the target BSS (Iu) in the PS Handover Required message, Forward Relocation Request message and the Relocation Request message.

The Radio Network part consists of:

– RRC Container shall contain START_PS /MS GERAN IU capabilities.

– Target Cell Id.

– Number of Iu instances. The value of the IE is set to 1 as defined in 3GPP TS 25.413 [23].

– Relocation Type. The value of the IE is set to "UE involved", as defined in 3GPP TS 25.413 [23].

5.6.1.4.2 Target to Source Transparent Container

In GERAN A/Gb mode -> GERAN Iu mode the Target to Source Transparent Container is encoded as the Target RNC to Source RNC Transparent Conatiner. It is sent from the target BSS (Iu) to source BSS in the Relocation Request Acknowledge message, Forward Relocation Response message and the PS Handover Required Acknowledge message.

The Radio Network Part consist of the RRC message used in GERAN Iu mode to perform handover, i.e. Radio Bearer Reconfiguration message. This message will be sent to the MS in the PS Handover Command message.

5.6.1.5 Content of GERAN Iu mode → GERAN A/Gb mode Transparent Containers

5.6.1.5.1 Source BSS to Target BSS Transparent Container

In GERAN Iu mode -> GERAN A/Gb mode the Source BSS to Target BSS Transparent Container is sent from the source BSS (Iu) to the target BSS in the Relocation Required message, Forward Relocation Request message and the PS Handover Request message.

The Radio Network part consists of the following:

– MS RAC.

– Inter RAT or mode handover Info with MS capabilities.

NOTE: START_PS and UE RAC shall be added to this IE.

5.6.1.5.2 Target BSS to Source BSS Transparent Container

In GERAN Iu mode -> GERAN A/Gb mode the Target BSS to Source BSS Transparent Container is sent from the target BSS to the source BSS (Iu) in the PS Handover Request Acknowledge message, Forward Relocation Response message and the Relocation Command message in order to support PS handover to GERAN A/Gb mode from GERAN Iu mode (RRC Cell_Dedicated state or RRC CELL_Shared state, only PS RABs established).

The Radio Network part consists of the required information for access in the target cell and the information on allocated radio resources: Uplink and downlink TBF parameters, PS Handover reference and generic parameters for access in the target cell (i.e. GPRS cell options, target cell "Cell Selection struct", global power control parameters, reference frequency lists, cell allocation, GPRS mobile allocation). Over the air interface this information is sent in the Handover from GERAN Iu mode Command message.

The Core Network (i.e. NAS Container for PS HO) part consists of the following parameters:

– an XID Command indicating Reset or ‘Reset to old XID parameters’ and the new IOV-UI for the target cell;

– the GPRS ciphering algorithm to be used in the target cell

5.6.1.6 Contents of the GERAN A/Gb mode → GAN mode Transparent Containers

5.6.1.6.1 Source BSS to Target BSS Transparent Container

In GERAN A/Gb mode -> GAN mode the Source BSS to Target BSS Transparent Container is sent in the PS Handover Required message, the Forward Relocation Request message and the PS Handover Request message.

The Radio Network part consists of the following:

– MS RAC.

– START_PS and UE RAC (for dual mode mobile stations).

NOTE 1: The START_PS and UE RAC are needed to support PS Handover to UTRAN/GERAN Iu mode.

NOTE 2: The way of transferring START_PS and UE RAC from the mobile station to the BSC, is to piggyback the RRC container INTER RAT HANDOVER INFO, which includes START_PS and UE RAC, to the Attach Complete and Routing Area Update Complete messages from the mobile station to the SGSN. The SGSN will then include this container in every CREATE-BSS-PFC message sent to the BSC.

5.6.1.6.2 Target BSS to Source BSS Transparent Container

In GERAN A/Gb mode -> GAN mode the Target BSS to Source BSS Transparent Container is sent in the PS Handover Request Acknowledge message, Forward Relocation Response message and the PS Handover Required Acknowledge message.

The Radio Network part consists only of the mandatory fields within the PS Handover Radio Resources IE carried within the PS Handover Command message.

The Core Network part (i.e. NAS Container for PS HO) consists of the following parameters:

– an XID Command indicating Reset or ‘Reset to old XID parameters’ and the new IOV-UI for the target cell;

– the GPRS ciphering algorithm to be used in the target cell, if it is different from the ciphering algorithm used in the source cell.

5.6.1.7 Contents of the GERAN A/Gb mode → E-UTRAN Transparent Containers

5.6.1.7.1 Source to Target Transparent Container

In GERAN A/Gb mode to E-UTRAN handover the Source to Target Transparent Container is encoded as the Source eNB to Target eNB Transparent Container. It is sent from the Source BSS to the target eNB in the PS Handover Required message, the Forward Relocation Request message and the Handover Request message.

The Radio Network part consists of:

– MS RAC

– Inter RAT handover Info (defined in 3GPP TS 25.331) containing the START_PS and UE RAC values, if available

– Target Cell Id.

5.6.1.7.2 Target to Source Transparent Container

In GERAN A/Gb mode to E-UTRAN handover the Target to Source Transparent Conatiner is encoded as the Target eNB to Source eNB Transparent Container. It is sent from the target eNB to source BSS in the Handover Request Acknowledge message, the Forward Relocation Response message and the PS Handover Required Acknowledge message.

The Radio Network Part consists of the RRC message used in E-UTRAN to perform handover, i.e. (RRC E-UTRA) HandoverCommand message contains the entire DL-DCCH-Message including the RRCConnectionReconfiguration message as defined in 3GPP TS 36.331 [31]. This message will be sent to the MS in the PS Handover Command message.

5.6.1.8 Contents of the E-UTRAN → GERAN A/Gb mode Transparent Containers

5.6.1.8.1 Source BSS to Target BSS Transparent Container

In E-UTRAN to GERAN A/Gb mode handover the Source BSS to Target BSS Transparent Container is sent from the Source eNB to the Target BSS in the Handover Required message, the Forward Relocation Request message and the PS Handover Request message

The Radio Network part consists of the following information:

– MS RAC IE.

– Inter RAT handover Info (defined in 3GPP TS 25.331) containing the START_PS and UE RAC values, if available.

– E-UTRAN INTER RAT HANDOVER INFO (defined in 3GPP TS 48.018, see also 3GPP TS 36.331).

5.6.1.8.2 Target BSS to Source BSS Transparent Container

In E-UTRAN to GERAN A/Gb mode handover the Target BSS to Source BSS Transparent Container is sent from the Target BSS to the Source eNB in the PS Handover Request Acknowledge message, the Forward Relocation Response message and the Handover Command message.

For PS handover from E-UTRAN to GERAN A/Gb mode the Radio Network part consist of the required information for access in the target cell and the information on allocated radio resources: uplink and downlink TBF parameters, PS Handover reference and generic parameters for access in the target cell (i.e. GPRS cell options, target cell "Cell Selection struct", global power control parameters, reference frequency lists, cell allocation, GPRS mobile allocation). Over the air interface this radio network container is sent within the MobilityFromEUTRACommand message.

The Core Network part (i.e. NAS Container for PS HO) consists of the following parameters:

– an XID Command indicating Reset or ‘Reset to old XID parameters’ and the new IOV-UI for the target cell;

– the GPRS ciphering algorithm to be used in the target cell.