Which network nodes in LTE network have MBMS header compression information?

Question

Which node take care of header compression ?

Answer 1

As per specification, BM-SC server implements header compression for the data coming from external network or MBMS content provider. While establishing a MBMS sesion, BM-SC server informs header compression to MME via MBMS-GW.

Answer 2

MBMS features was introduced to save radio resources and providing the same content to a large number of audience. LTE supports ROHC i.e. Robust Header Compression for the dedicated user plane packets.

In LTE network, dedicated downlink data flows from PGW ------> SGW -------> ENB--------> UE. In this flow, when user plane packet reaches to ENB, it performs header compression and send the compressed packets to UE over the air. But in case of multicast/broadcast, the same data flows through # number of eNodeBs. Reason being, if header compression is allowed then BM-SC server itself does it and BM-SC also informs to MME via MBMS-GW by using "MBMS IP Multicast Distribution" IE within the MBMS session start request message.

I hope this will help.

Comments

So in this case who does the decompression at UE side ?

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Decompression at UE side should be same as non MBMS :)