Acronym for Stream Control Transmission Protocol.
SCTP is a type of mobility management for IP-based networks that focuses on the transport and session layers, rather the network layer. SCTP, in general terms, is a reliable transport protocol operating on top of potentially unreliable connectionless packet service such as IP.
SCTP can be used as the transport protocol for applications where monitoring and detection of loss of session is required. For such applications, the SCTP path/session failure detection mechanisms, especially the heartbeat, will actively monitor the connectivity of the session. SCTP offers recognized error-free non-duplicated transfer of messages. Detection of data loss, data corruption and duplication of data is achieved by using checksums and sequence numbers. A selective retransmission mechanism is applied to correct loss or corruption of data.
SCTP connections are established after a 4-way handshake between two SCTP endpoints, usually a client and a server. The server, after having received the client’s association setup request, returns an acknowledgement of the setup request containing a data structure called cookie, which is protected by a secure message authentication code, and does not change state. Only when this cookie is returned by the client unchanged does the server allocate resources and establish a new association.
With its inception, SCTP was designed to provide a general purpose transport protocol for message-oriented applications. It has been designed by the IETF SIGTRAN working group, which has released the SCTP standard draft document ( RFC2960 ) in October 2000. Its design includes appropriate congestion avoidance behavior and resistance to flooding and masquerade attacks.