Stream Control Transmission Protocol, Application And Network Simulation

SCTP(Stream Control Transport Protocol),standardized by the InternetEngineering Task Force(IETF) is a new general-purpose transport protocol which fitto transmit stream media because of it's new advantages such as multi-streamtransport, unordered deliver and so on. In this issue, we discuss how to use SCTP totransport MPEG-4 video media, and build up a Video-on-Demand system on Linux. In order to understand the protocol,the first part of this article describe the designan operation of SCTP,includes the basic datagram format and the concept ofChunk,Association,Stream, etcetera. Implement of SCTP needs the support of OS,many Unix-like OS such as Linux,Solaris and FressBSD have build SCTP support into their basic system .Since ourVoD system was set up on Linux,we will delve into Linux kernel to find how the initprocedure register SCTP into the IP stack and the Socket API provide by SCTP. A particular application needs not only transport protocol but also other practicalmechanism. RTP(Real-time Transport Protocol) provide a framework to specify theprofile and payload format of a media session. Our system will use RTP/SCTP to support the ULP(Upper Layer Protocol),try to reduce the impact of video play-back quality due to data pakets loss duringtransport through Selective retransmission,and our retrasmission will benifited by thefeature of SCTP such as:1)Multiple streams in a single association2)Unordered message delivery In the end of this issue,we made several network simulation of SCTP with thewidely used tool,Network Simulator Version 2,to verify and discuss the mostimportant feature of SCTP: congestion control and multi-homed. As a conclusion,we give a theorical discussion of SCTP and talk about somefuture work.