Unlike UDP and TCP, the protocol supports multihoming and redundant paths to increase resilience and reliability.
The SCTP reference implementation was released as part of FreeBSD version 7, and has since been widely ported to other platforms.
In contrast, TCP is a stream-oriented protocol, transporting streams of bytes reliably and in order.
In essence, it involves bundling several connections into a single SCTP association, operating on messages (or chunks) rather than bytes.
SCTP, on the other hand, assigns a sequence number or a message-id[note 1] to each message sent in a stream.
[6] SCTP has seen adoption in the mobile telephony space as the transport protocol for several core network interfaces.
[note 2] Eight flag bits, a two-byte length field, and the data compose the remainder of the chunk.
Although encryption was not part of the original SCTP design, SCTP was designed with features for improved security, such as 4-way handshake (compared to TCP 3-way handshake) to protect against SYN flooding attacks, and large "cookies" for association verification and authenticity.
Some operating systems ship with SCTP support enabled, and, as it is not as well known as TCP or UDP, it is sometimes overlooked in firewall and intrusion detection configurations, thus often permitting probing traffic.
The SCTP reference implementation runs on FreeBSD, Mac OS X, Microsoft Windows, and Linux.