Microsoft S+M (Microsoft Speed + Mobility) is an experimental networking protocol developed primarily at Microsoft for transporting web content. Microsoft S+M is similar to HTTP, with particular goals to reduce web page load latency and improve web security. As a revision of Google's SPDY protocol, Microsoft S+M achieves reduced latency through SPDY's use of compression, multiplexing, and prioritization.
Relation to HTTP
Microsoft S+M, being built on SPDY, does not replace HTTP. Rather, it modifies the way HTTP requests and responses are sent over the wire; this means that all the existing server-side applications can be used without modification if a SPDY-compatible translation layer is put in place. When sent over SPDY, the HTTP requests are processed, tokenized, simplified and compressed. For example, each SPDY end-point keeps track of which headers have been sent in the past requests and can avoid resending the headers that have not changed; those that must be sent are sent compressed.
In developing HTTP Speed+Mobility, Microsoft built upon both Google's proven SPDY protocol and on WebSocket, which is a web technology providing for bi-directional, full-duplex communications channels over a single TCP connection.
Besides support of the framing of WebSockets, changes from SPDY include the following: taking mobile phones and other low-power devices into account and the removal of SPDY’s obligatory use of CPU-intensive features—encryption, compression, and server-side push.
- "HTTP Speed+Mobility". White Paper. Retrieved 2012-03-29.
- "SPDY: An experimental protocol for a faster web". Chromium Developer Documentation. Retrieved 2009-11-13.
- MSDN blog: Speed and Mobility: An Approach for HTTP 2.0 to Make Mobile Apps and the Web Faster
- ExtremeTech: S&M vs. SPDY: Microsoft and Google battle over the future of HTTP 2.0
- CNET: Microsoft: Google's SPDY is nice for a faster Web, but...
- Nottingham, Mark. "What's next for HTTP". Retrieved 2012-05-18.