The Stream Control Transmission Protocol (SCTP) is a transport-layer protocol, serving in a similar role to the popular protocols Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). It’s message-oriented like UDP and ensures reliable, in-sequence transport of messages with congestion control like TCP.

Features of SCTP include:

  • Multihoming support in which one or both endpoints of a connection can consist of more than one IP address, enabling transparent failover between redundant network paths.
  • Delivery of chunks within independent streams eliminate unnecessary head-of-line blocking, as opposed to TCP byte-stream delivery.
  • Path selection and monitoring to select a primary data transmission path and test the connectivity of the transmission path.
  • Validation and acknowledgment mechanisms protect against flooding attacks and provide notification of duplicated or missing data chunks

Although encryption was not part of the original SCTP design, SCTP was designed with features for improved security, such as 4-way handshake  to protect against SYN flooding attacks, and large “cookies” for association verification and authenticity. Multihoming enables an association to stay open even when some routes and interfaces are down.