Section: 6.5.4.6 Abnormal cases on the network side
Content: The following abnormal cases can be identified: a) Unknown EPS bearer context: If the EPS bearer identity provided in the EPS bearer identity for packet filter IE in the BEARER RESOURCE MODIFICATION REQUEST message indicates an EPS bearer identity value and this does not belong to any already activated EPS bearer context, the MME shall reply with a BEARER RESOURCE MODIFICATION REJECT message with ESM cause #43 "invalid EPS bearer identity". b) BEARER RESOURCE MODIFICATION REQUEST message received for a PDN connection established for emergency bearer services: The MME shall reply with a BEARER RESOURCE MODIFICATION REJECT message with ESM cause #30 "request rejected by Serving GW or PDN GW". c) Collision of UE requested bearer resource modification procedure and EPS bearer context modification procedure: The handling of the same abnormal case as described in clause 6.4.3.6 applies. d) BEARER RESOURCE MODIFICATION REQUEST message received from a UE which is in a location where the PLMN is not allowed to operate: If the MME determines that the UE is in a location where the PLMN is not allowed to operate, the MME discards the message.