- Dedicated EPS bearer context activation procedure is to establish an EPS bearer context with specific QOS and TFT between UE and EPC.
- This procedure is initiated by the network
- UE can also request for dedicated bearer by sending resource allocation request or modification request
- MME will initiate dedicated EPS bearer context activation by sending ACTIVATE_DEDICATED_EPS_BEARER_CONTEXT_REQUEST
- The dedicated bearer which will be associated with a default bearer will be identified by the linked EPS bearer identity field in dedicated bearer activation request.
- The linked EPS bearer id also indicates which IP address, PDN the dedicated bearer is linked.
- For all uplink traffic flows to radio bearer UE should use the TFT received in bearer activation request.
·
UE may reject the request with causes such as
o
#26 Insufficient resources
o
#43 Invalid EPS bearer identity
o
#41 Invalid TFT operation.
Reference : 3GPP TS 23.401