Question #661412 on rohc changed: https://answers.launchpad.net/rohc/+question/661412
Didier Barvaux requested more information: Hello, I analyzed the 39 packets. Here are some points that I noticed and some related questions for you: * You seem to have configured the ROHC compressor with MAX_CID = 3 since the compressor uses CID=0,1,2,3 for packets #1-4 and then re-uses CID=0 for packet #5. Is that correct? * The ROHC compressor re-uses CID=0 for packets #5-18 although they are different streams (ie. different UDP destination ports). That's strange. Did you specified some timing information for every packet to the ROHC compressor? The ROHC compressor uses a Least Recently Used (LRU) algorithm to determine which context to re-use first. Without timing info, the LRU algorithm does not work well. The ROHC compressor always re-uses CID = 0. Look at the way the non-regression test uses the timing information from the PCAP capture file to provide some timing information to the ROHC compressor: https://github.com/didier- barvaux/rohc/blob/master/test/non_regression/test_non_regression.c#L884 * The ROHC compressor uses the Uncompressed profile for packets #19-24 and #27. They are TCP packets. They could have been compressed with the TCP profile or the IP-only profile instead of the Uncompressed profile. Are the TCP and IP-only profiles disabled? * The ROHC compressor compresses the packets #28-39 as one IP/UDP stream. The first 3 packets are compressed with IR packet types to establish the context. The next 9 packets are encoded as UO-0 packets. They look fine. The Sequence Number (SN) looks OK according to the previous IR packets. So are the encoding of the IP-ID and UDP checksum fields. They are correctly decompressed with the ROHC library. Please confirm my hypothesis. And try to solve the timing problem at the compressor side, it might be a source of confusion for the Mobile ROHC decompressor. Regards, Didier -- You received this question notification because your team ROHC Team is an answer contact for rohc. _______________________________________________ Mailing list: https://launchpad.net/~rohc Post to : rohc@lists.launchpad.net Unsubscribe : https://launchpad.net/~rohc More help : https://help.launchpad.net/ListHelp
