A router can also be used to provide this function. However, the difference
between a router and firewall is that a router is designed in principle to let
all packets through, which makes it necessary to register packets that are
to be blocked. In contrast, a firewall is designed in principle to block all
packets, which makes it necessary to register the packets that are to be let
through.
Company network (company LAN)
Web server
for internal use
Protection
from outside
Firewall
Chapter 9
Unauthorized intrusion
Internet
Technology element
Router
(5)Installing a proxy server
A “proxy server,” also called an “application gateway,” is a server that
acts as a communications gateway for company computers to access the
Internet.
●Communications gateway
When a company computer connects to the Internet, the connection is
routed through a proxy server acting as a gateway. Using a proxy server as
a gateway makes it possible to conceal the IP address of each computer
(private IP address). From the perspective of the Internet, communications
are conducted with the proxy server, which reduces the risk of attacks on
company computers.
In addition, a proxy server can temporarily store (cache) data that has been
accessed, which speeds up the process when accessing the same data the
next time.
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