Answer:An external caching scheme stores copies of web objects
or meta-data so that clients can avoid requests to a web
server. The best known example of an external cache is a
web proxy, but with the rapid spread of web technologies,
many other caching scenarios can be identified. Caching
is central to performance in the web, both because it re-
duces load on servers, and because cached data is normally
cheaper to access from another machine that is closer in the
network. Although cooperation between cache managers is
not a common feature of existing web architectures, coop-
erative caching supported by peer-to-peer architectures has
great potential [9, 13]. When sets of client systems have sim-
ilar interests and fast low-latency interconnections, shared
caching could bring significant benefits.
The peer-to-peer mechanisms referred to
Explanation: