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Stream Control Transmission Protocol |
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Stream Control Transmission Protocol
Background and History The Stream Control Transmission Protocol (SCTP) was developed by the IETF's SIGTRAN working group for the transport of signalling protocols (like SS7) over IP networks. The traditional IP transport protocols, TCP and UDP, are unsuitable as they do not meet the stringent performance requirements of telecommunications signalling protocols. The Stream Control Transmission Protocol is based on a proposal submitted by R. Stewart and Q. Xie on the Multi-Network Datagram Transmission Protocol (MDTP).
Work on MDTP had started independently in 1997 to address TCP's weaknesses. MDTP was an application level protocol that worked above UDP. By the time work on SCTP started within the IETF, MDTP was a working implementation and met most of SIGTRAN's requirements for a transport protocol. The Multi-Network Datagram Transmission Protocol was also the only protocol, submitted to the IETF, that supported multihoming and avoided head-of-line blocking. The MDTP proposal went through significant changes within the IETF and eventually formed the basis of the Stream Control Transmission Protocol. One of the changes included, allowing SCTP to run directly over IP.
The Stream Control Transmission Protocol was initially designed as a transport protocol for telephony applications but it has much broader applications, and can be considered as an alternative to TCP in many application scenarios. Some of the other potential applications of SCTP include:
- Database applications
- Multiple simultaneous independent non-blocking transactions.
- Path diversity between synchronised and replicated systems.
- Reliable Server Pooling
- A next generation transport protocol for HTTP, that can support parallel web page content downloads.
- Mobility with multi-homed mobile terminals.
Some of SCTP's features include:
- acknowledged error-free and non-duplicated transfer of user data,
- data fragmentation to conform with the discovered path MTU size,
- sequenced delivery of user messages within multiple streams, with an option for order-of-arrival delivery of individual user messages,
- optional bundling of multiple user messages into a single SCTP packet
- network-level fault tolerance through the support of multi-homing at either or both ends of an association, and
- multiplexing of traffic from multiple SCTP users.
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3G Information 
