What Is SCTP?

Date First Published: 14th May 2022

Topic: Computer Networking

Subtopic: Internet Protocols

Article Type: Computer Terms & Definitions

Difficulty Level: 8/10

Learn more about what SCTP is in this article.

Short for Stream Control Transmission Protocol, SCTP, also known as next-generation Transmission Control Protocol or TCPng, is a transport-layer protocol used for transmitting multiple streams of data between two devices that have established a connection to a network at the same time. Multihoming and redundant paths are supported by this protocol in order to increase its reliability. It was defined in RFC 4960 by the IETF Signalling Transport Working Group in October 2000. It is maintained by the IETF Transport Area working group.

Features Of SCTP

The features of SCTP are:

• Reliable transmission of ordered and unordered data streams.
• Validation and acknowledgement functionality to provide protection against flooding attacks and notify duplicated or missing data chunks.
• Path selection and monitoring for selecting and testing the connectivity of a data transmission path.
• Multihoming support, where the devices of a connection can contain multiple IP addresses to increase reliability and performance.
• Delivery of data chunks within separate streams, completely eliminating unnecessary head-of-line blocking rather than TCP byte-stream delivery.
• Detection of data loss, data corruption, and data duplication, achieved through the use of checksums and sequence numbers.

Data Streams In SCTP

SCTP has multistreaming capabilities. This allows the delivery of data in separate streams. Unlike TCP which transmits data in a single stream, also known as a byte stream and delays the delivery of data in the event of data loss or errors during the transmission process, data loss in one stream will have no effect on the delivery for the other streams, meaning that the whole transmission process will not be delayed. Also, it resolves the issue of web browsers being limited to handling only two connections at the same time, since extra streams can be opened to reduce the load on the server, reducing latency.

Multihoming In SCTP

Multihoming refers to the process of connecting a host to more than one network in order to increase its reliability or performance. In SCTP, support for multihoming means that connected devices can have alternative IP addresses associated with them, in the event that the other IP address fails. This allows SCTP to make multiple connection paths between two devices. In other words, it enables the device to get around a network failure. In addition, SCTP does not rely on the IP layer for resilience. Overall, multistreaming and multihoming are the greatest advantages of SCTP.