Hi, I find that Release 4 and Release 5 of 3GPP support both IPHC and ROHC. But which is popular in the release 4 & release 5 ?
Further, In GSM and IS-95,the 0-byte header compression is used to completely eliminate the headers for a majority of the packets during normal operation and the functionalities available in1-octet header scheme is available from the lower layer functionalities.
In CDMA2000, I assume that the 'Header Removal' might be applicable whenever the RTP/UDP/IP information is not required at the UE/MS.
However, there are other options that are available in CDMA 2000 -
- Link Layer Assisted Robust Header Compression
I understand that the limited bandwidth of wireless links makes it impossible to transmit the entire IP/UDP/RTP header with every packet and So,arrived the ROHC mechanism that only transmits the fields that change rather than the entire header, but still maintain context information.
To overcome the limitation of sending atleast1 octet of header information in ROHC,there is a feature that uses the synchronous characteristics of physical channel layer to replace the compressed header information.
But, which (ROHC or LLA ROHC) is widely implemented and used in the following - CDMA2000 1X(IS-2000) / 1xRTT CDMA2000 EV-DO (Rev 0/A/B) Any ideas ?
Thx in advans, Karthik Balaguru