Section: 7.3.10 Forward Access Context Notification
Content: A Forward Access Context Notification message shall be sent from the Old SGSN to the New SGSN over the S16 interface to forward the RNC contexts to the target system, or sent from the Old MME to the New MME over the S10 interface to forward the RNC/eNodeB contexts to the target system. When the old SGSN receives the RANAP message Forward SRNS Context, the old SGSN shall send a Forward Access Context Notification message to the new SGSN. The new SGSN shall forward the message to the target RNC using the corresponding RANAP message. When the old SGSN receives a BSSGP message PS handover Required and the acknowledged peer-to-peer LLC operation is used for the Bearer Context or when "delivery order" is set in the Bearer Context QoS profile, the old SGSN shall send a Forward Access Context Notification message with the PDU Number IE to the new SGSN. The new SGSN shall forward the message to the target RNC/ target BSS using the corresponding RANAP message only for PS handover to Iu mode. When the old SGSN receives a BSSGP message PS handover Required from source BSS/RNC for PS handover to A/Gb mode, the value part of RAB Context IE shall be empty according to its defined minimum length. Table -1 specifics the presence requirements and conditions of the IEs in the message. Table 7.3.10-1: Information Elements in a Forward Access Context Notification