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Is eMBMS data cyphered ?

+3 votes
1,830 views

When eMBMS gateway sends data to eNodeB then does eNodeB cyphered data or not. Suppose a set of user (known as multi casting) is on going then would PDCP be performed ROHC and cyphering or not for that set of users ?

posted Sep 9, 2013 by Vikram Singh

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In my understanding MCCH/MTCH data is transperent to PDCP layer. 3GPP 36.323 doesnt talk about MCCH/MTCH data processing at all.
Only RLC UM mode with 5 bit SN and t-reordering is 0. As its multicast data without ARQ so applying ROHC doesnt make sense.
commented Sep 17, 2013 by Prasad D
http://s3.amazonaws.com/sdieee/222-eMBMS_tech_overview_IEEE_112712.pdf
commented Sep 17, 2013 by Prasad D

1 Answer

+1 vote

Ideally yes, eMBMS sits in the core network and connection between MME and eNodeB is secure so on the similar lines eNodeB and eMBMS should also be the same. otherwise there would be a issue with the concept of RAN operator and Core Network operator.

answer Sep 9, 2013 by Luv Kumar
eNodeB and MME has control plane. when SGW sends data to eNodeB in point to point communication (normal data flow) . PDCP performs encryption and ROHC of the received packet since a Keyrrc encryption is applicable to an UE. this query is little bit related to key generation part. Since Keyrrc encryption is per user basis then how a mulitcast data can be cyphered by eNodeB ? since in multicasting and broadcasting a data over the radio is access by set/all users from the same place(same resource blocks). Now question how data is being protected by eNodeB ? is it a different Key all together to protect multicast data or eMBMB gateway do some thing to secure multicast data ?
commented Sep 9, 2013 by Vikram Singh
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