Stream Control Transmission Protocol (SCTP)

- SCTP - The Next Generation TCP

Stream Control Transmission Protocol (SCTP) is a protocol for transmitting multiple streams of data at the same time between two end points that have established a connection in a network. Sometimes referred to as "next generation TCP" (Transmission Control Protocol) - or TCPng. SCTP is designed to make it easier to support a telephone connection over the Internet (and specifically to support the telephone system's Signaling System 7 - SS7 - on an Internet connection). A telephone connection requires that signaling information (which controls the connection) be sent along with voice and other data at the same time. SCTP also is intended to make it easier to manage connections over a wireless network and to manage the transmission of multimedia data. SCTP is a standard protocol (RFC 2960) developed by the Internet Engineering Task Force (IETF).

SCTP for Data Center Applications

The data centers represent the foundation of the Internet and computer services specially E-business service and high performance computing. Nowadays, the development of web services is based on the increased size and the complexity of the processed data. It is clear that the data centers continue to grow for higher performance and better availability. Hence, this remarkable growth in the data centers has motivated researchers to improve speed and capacity of data transfer. 

Due to the heavy load of network traffic, TCP does not provide satisfactory performance in controlling congestion in data centers over the network. Thus, the network suffers from loss of confidential data. Although, TCP is deployed into the data centers, it does not have the capacity to control the huge amount of data. There are several fuzzy questions about transparency of TCP protocol that is connected with IP protocol for supporting the applications of data centers. In data centers, there is a demand of high data rates, low latencies, high robustness and high availability. 

In spite of, the weaknesses of the standard TCP protocol to fit into the data centers are well known, it is impossible to do considerable changes on the standard TCP protocol. However, there are several alternative variants of TCP which are used in the areas where TCP cannot work. For example, SCTP which is a connection-oriented transport protocol that provides reliable stream oriented services similar to TCP. SCTP is especially designed to be used in situations where reliability and near real-time considerations are important as well as it is designed to run over existing IP/Ethernet infrastructure. Moreover, SCTP was designed to support Signaling System number 7 (SS7) layers which have unique features that are suitable for data centers. Also, SCTP has many promising features including flexibility, robustness, and extensibility. Therefore, SCTP protocol is a better choice for data centers. 

SCTP is another TCP alternative that has been in development since 2000, but the adoption has been slow since it requires native operating system support.

[More to come ...]