diff --git a/Documentation/networking/dccp.txt b/Documentation/networking/dccp.txt new file mode 100644 index 0000000000000000000000000000000000000000..c45daabd3bfe50b045316373c809b5d8a7f4ff22 --- /dev/null +++ b/Documentation/networking/dccp.txt @@ -0,0 +1,56 @@ +DCCP protocol +============ + +Last updated: 10 November 2005 + +Contents +======== + +- Introduction +- Missing features +- Socket options +- Notes + +Introduction +============ + +Datagram Congestion Control Protocol (DCCP) is an unreliable, connection +based protocol designed to solve issues present in UDP and TCP particularly +for real time and multimedia traffic. + +It has a base protocol and pluggable congestion control IDs (CCIDs). + +It is at draft RFC status and the homepage for DCCP as a protocol is at: + http://www.icir.org/kohler/dcp/ + +Missing features +================ + +The DCCP implementation does not currently have all the features that are in +the draft RFC. + +In particular the following are missing: +- CCID2 support +- feature negotiation + +When testing against other implementations it appears that elapsed time +options are not coded compliant to the specification. + +Socket options +============== + +DCCP_SOCKOPT_PACKET_SIZE is used for CCID3 to set default packet size for +calculations. + +DCCP_SOCKOPT_SERVICE sets the service. This is compulsory as per the +specification. If you don't set it you will get EPROTO. + +Notes +===== + +SELinux does not yet have support for DCCP. You will need to turn it off or +else you will get EACCES. + +DCCP does not travel through NAT successfully at present. This is because +the checksum covers the psuedo-header as per TCP and UDP. It should be +relatively trivial to add Linux NAT support for DCCP.