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Glossary
Alternates
Different versions of the same web object.
Some web servers answer requests to the same
URL with a variety of objects. The content of
these objects can vary widely, depending on
whether a server delivers content for different
languages, targets different browsers with
different presentation styles, or delivers
variable content at different times of the day.
ARM
Adaptive Redirection Module. Used in
transparent proxy caching, ARM is an Intel
NetStructure Cache Appliance component that
redirects intercepted client traffic destined for
an origin server to the Intel NetStructure Cache
Appliance application. Before the traffic is
redirected by the ARM, it is intercepted by an
L4 switch or router.
Cache
Stores copies of frequently accessed objects
close to users and serves them to users when
requested. See also Object store.
Cache hierarchy
Levels of caches that communicate with each
other. All cache hierarchies recognize the
concepts of Parent cache and Child cache.
Cache hit
An object in the cache that can be served
directly to the client.
Cache miss
An object that is not in the cache or that is in
the cache but no longer valid. In both cases, the
Intel NetStructure Cache Appliance must get
the object from the Origin server.
Caching web proxy server
A web proxy server with local cache storage
that allows the proxy to fulfill client requests
locally, using a cached copy of the origin
server’s previous response.
CGI
Common Gateway Interface. A set of rules that
describe how a web server and another piece of
software (a CGI program) located on the same
machine communicate.
cgi-bin
The most common directory name on a web
server in which CGI programs are stored.
Child cache
A cache lower in a Cache hierarchy for which
the Intel NetStructure Cache Appliance is a
parent. See also Parent cache.