A proxy that focuses on World Wide Web(WWW) traffic is called a "web proxy".
The most common use of a web proxy is to serve as a
web cache.
Most proxy programs (e.g. Squid, NetCache) provide a means to deny access to
certain URLs in a
blacklist,
thus providing content filtering. This is usually used in a corporate
environment, though with the increasing use of Linux in small businesses and
homes, this function is no longer confined to large corporations. Some web
proxies reformat web pages for a specific purpose or audience (e.g., cell phones
and PDAs).
A
content filtering web proxy server like
SafeSquid[1]
or
DansGuardian helps distribute Internet access while providing control to the
administrators over the content delivered. It is usually used in organizations
or schools to ensure that Internet usage conforms to the local
acceptable use policy. A content filtering proxy must necessarily
accommodate the demands of granular rules for Internet access privileges and
restrictions across an enterprise.
A content filtering proxy can be used to filter out unwanted content, using
methods such as
URL
or
DNS blacklists,
URL
filtering, MIME
filtering, or keyword filtering.
A content filtering proxy may support
authentication, to control access to the web. It usually produces
logs,
either to give detailed information about the URLs accessed by specific users,
or to monitor
bandwidth usage statistics. It may also communicate to
daemon based and
ICAP based
antivirus software to provide security against virus and other
malware by
scanning incoming content in real time before it enters the network.
An anonymous proxy server (sometimes called a web proxy) generally attempts
to anonymize web surfing. These can easily be overridden by site administrators,
and thus rendered useless in some cases. There are different varieties of
anonymizers.
Access control: Some proxy servers implement a logon requirement. In large
organizations, authorized users must log on to gain access to the
web.
The organization can thereby track usage to individuals.
