Internet Cache Protocol
The Internet Cache Protocol (ICP) is a protocol used for coordinating web caches. Its purpose is to find out the most appropriate location to retrieve a requested object from.
Hierarchically, a queried cache can either be a parent, or more commonly a sibling. These differ inasmuch as that a parent will resolve cache misses, while a sibling will not.
The ICP protocol is described in RFC 2186, its application to hierarchical web caching in RFC 2187.
The ICP protocol was designed to be lightweight in order to minimize round-trip time between caches. It is intended for unreliable but quick connections, using short time-outs before a cache starts to retrieve an object on its own. UDP is commonly used as delivery protocol.
Web proxies that support ICP:
- Squid cache
- Microsoft Proxy
- Cisco Content Engine
External links
Categories: Computer stubs | Internet protocols