Question

What is SRB1/BIS in LTE and where it will be usefull?

Answer 1

This page describes LTE Signalling Radio Bearer types which include LTE SRB0, SRB1 and SRB2. LTE Signalling radio bearers(SRB) are used for the transfer of RRC and NAS signalling messages. 
•  RRC messages are used as signalling between UE and eNodeB.
•  NAS(Non Access Stratum) messages are used as signalling between UE and MME.

RRC messages can be used to encapsulate NAS messages for their transfer between UE and eNodeB. The S1 application protocol is later used to transfer NAS messages between eNode and MME.


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