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LTE: Does RLC segmentation and reassembling applicable for MBMS data ?

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MBMS Data receives from MBMS-GW to eNodeB module interfacing towards MBMS-GW. It removes GTP-U header and sends data to lower layer i.e RLC. As per my understanding so far, RLC does segmentation and re-assembling for the received upper layer PDU to make it fit into MAC PDU. Now I want to know, Does the same concept applicable for MBMS data also or for RLC it is transparent mode transmission.

Which format is used by RLC for the MBMS transmission ?

posted Nov 13, 2016 by Rupam

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1 Answer

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I have minimal information to share on MBMS logical channels. MCCH and MTCH both logical channels are mapped to RLC UM mode. RLC UM mode transmission is used for delay sensitive services and also when data flow direction is uni directional such as MTCH (point to multi-point transmission) . Though RLC UM entity supports segmentation and re-assembling, I think this is not applicable for MCCH and MTCH since there is a parameter "UM_Window_Size". Value of this parameter is set to zero for MCCH and MTCH. I am still not fully confirmed.

answer Nov 16, 2016 by Vimal Kumar Mishra
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