http://en.wikipedia.org/wiki/Stream_Control_Transmission_Protocol

因為TCP的一些限制而出現了SCTP，

TCP provides both reliable data transfer and strict order-of-transmission delivery of data. Some applications need reliable transfer without sequence maintenance, while others would be satisfied with partial ordering of the data. In both of these cases, the head-of-line blocking offered by TCP causes unnecessary delay. 提供能夠靈活拆分組裝的TCP

The stream-oriented nature of TCP is often an inconvenience. Applications must add their own record marking to delineate their messages, and must make explicit use of the? push facility ?to ensure that a complete message is transferred in a reasonable time. 基于stream的不如基于消息的用起來簡單

The limited scope of TCP sockets complicates the task of providing highly-available data transfer capability using? multi-homed hosts. 自動容錯支持的不好，比如我給一批IP都可以服務請求，一個壞了其他自動接入，當前TCP要靠外部工具來完成

TCP is relatively vulnerable to denial-of-service attacks, such as? SYN attacks . 易受攻擊

?

所以SCTP的feature就是跟上面的問題一一對應：

Multihoming ?support in which one or both endpoints of a connection can consist of more than one IP address, enabling transparent fail-over between redundant network paths. 多個IP可以綁定，自動容錯

Delivery of chunks within independent streams eliminate unnecessary? head-of-line blocking , as opposed to TCP byte-stream delivery. 多路stream，不用排隊

Path selection and monitoring select a primary data transmission path and test the connectivity of the transmission path. 選擇一條最好的路徑，TCP是沒有的，只能靠IP自己調優了

Validation and acknowledgment mechanisms protect against flooding attacks and provide notification of duplicated or missing data chunks.

Improved error detection suitable for? Ethernet jumbo frames . 驗證更多了，四次捂手

SCTP 一句話介紹