Section: 6.4.1.4 Default EPS bearer context activation not accepted by the UE
Content: If the default EPS bearer context activation is part of the attach procedure, the ESM sublayer shall notify the EMM sublayer of an ESM failure. If EMM-REGISTERED without PDN connection is supported by the UE and the MME, the ESM sublayer shall additionally provide an ACTIVATE DEFAULT EPS BEARER CONTEXT REJECT message to the EMM sublayer. If the default EPS bearer context activation is not part of the attach procedure, the UE shall send an ACTIVATE DEFAULT EPS BEARER CONTEXT REJECT message and enter the state BEARER CONTEXT INACTIVE. The ACTIVATE DEFAULT EPS BEARER CONTEXT REJECT message contains an ESM cause that typically indicates one of the following cause values: #26: insufficient resources; #31: request rejected, unspecified; or #95 – 111: protocol errors. Upon receipt of the ACTIVATE DEFAULT EPS BEARER CONTEXT REJECT message, the MME shall enter the state BEARER CONTEXT INACTIVE and stop the timer T3485, if the timer is running.