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Unformatted text preview: organization because the Internet is an open environment.
There may be virus attacks on the organization's computing resources and other
security problems through the Internet. To handle this problem, organizations
often use a proxy server, which is a computer system that is specially configured
to allow other computers of an organization to interact with the Internet through it.
When only a single proxy server interacts with the Internet, security can be easily
maintained because the single server can be kept more secure than hundreds of
individual computers on a network.
With proxy server, the Internet is accessed from within the organization in the
following manner. When someone from the organization specifies the URL of a
server on the Internet using the browser on his/her computer, the user's request is
first sent to the proxy server. The proxy server then contacts the server on the
Internet and then the proxy server sends the requested information from the
Internet server to the user's computer. All this is transparent to the user. That is,
the user gets a feeling that he/she is directly accessing the Internet server specified
in the URL. By acting as an in-between system, the proxy server can maintain
security as well as log all traffic between the Internet and the organization's
network of computers.
A proxy server is typically used in an organization to provide one or more of the
1. To serve as a firewall. A firewall controls the flow of incoming and outgoing
messages from within an organization for providing better security to the organization. For example, the firewall software running on the proxy server can
be configured for packet filtering to ensure that only certain packets are permitted
to flow from the inside to the outside world. Similarly, the firewall software can
be configured to allow telnet to a computer within the organization only from
those computers of the outside world whose IP addresses have been pre-registered
in the proxy server. Many firewalls also permit establishment of port filters on a
per host or subnet basis, allowing the network administrator to control access on a
fine grained ba...
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This document was uploaded on 04/07/2014.
- Spring '14