Question #162063 on rohc changed: https://answers.launchpad.net/rohc/+question/162063
Cedric Baudoin proposed the following answer: Hi, Actually, the IP/UDP compression is based on the fact that some UDP fields can be deduced from IP header fields. ROHC achieve high compression gain thanks to redundancy between fields of same layer (e.g. UDP) for a given flow AND by redundancy between fields of the various stacks (e.g between IP and UDP and RTP). So you can of course use some of the techniques used in ROHC for an UDP-only (i.e. without IP) but probably won't be as efficient if you don't consider the whole header stack Best regards Cédric 2011/6/20 Subin <[email protected]> > Question #162063 on rohc changed: > https://answers.launchpad.net/rohc/+question/162063 > > Status: Needs information => Open > > Subin gave more information on the question: > Hello Didier, > > Thanks for the fast response. Does IP/UDP profile always go together and > not just one of IP or UDP header compression alone? Please find below > more details. > > Basically my question is if I can separate "transport layer(UDP)" header > compression from the "IP" header compression for the same packet. That > is, can I use the library to compress only the UDP header of the packet. > Then later use the library to compress the IP header of the same > compressed packet? In other words is it like IP/UDP together constitute > as a compression scheme/ profile or are the compression profiles > independent? > > Just to give a background of why this is important for me is that I have > a channel with fixed transmission unit(136 byte). The compressed ROHC > packet has different sizes and padding with zeros to make a fixed > transmission unit is not efficient. So if its possible to separate the > compression schemes, I could do different processing at the transport > layer and the IP layer so that channel could be utilised fully. > > Thanks, > Subin > > -- > You received this question notification because you are a member of ROHC > Team, which is an answer contact for rohc. > > _______________________________________________ > Mailing list: https://launchpad.net/~rohc > Post to : [email protected] > Unsubscribe : https://launchpad.net/~rohc > More help : https://help.launchpad.net/ListHelp > -- You received this question notification because you are a member of ROHC Team, which is an answer contact for rohc. _______________________________________________ Mailing list: https://launchpad.net/~rohc Post to : [email protected] Unsubscribe : https://launchpad.net/~rohc More help : https://help.launchpad.net/ListHelp
