Proxy servers may be a valuable contribution to network security. Particularly when internet traffic is created by internal users.
When a proxy server is implemented, all HTTP traffic by these internal users is handled by this proxy server. Internal users can only access the internet through this server, there is no direct connection to the internet.
Qi ict engineers proxy-servers by Blue Coat.
Proxy server pro's and con's
Applying proxy servers offers a range of advantages and some (minor) disadvantages:
Proxy server pro's
Since all HTTP traffic runs through the proxy server, the proxy server potentially is able to check all traffic. Thus, it may be established very selectively if a user has permission to visit the selected URL. Blue Coat systems are able to define very precisely which permissions are set per user or user group.
When your proxy server is combined with a virus scanner, web pages can be checked for viruses. Also, proxy servers offer caching facilities, allowing web content to be delivered to the end-user much faster, effecting reduction of traffic load to the internet connection.
Proxy server con's
Proxy servers do have disadvantages: they handle user-traffic via HTTP, but do not support FTP and other protocols like SMTP / POP. These will need to be checked by alternative systems such as firewalls, antivirus and intrusion prevention systems.
Implementing proxy servers
Within a network, a proxy server may be implemented either transparently or non-transparently. Through transparent implementation, a router or layer 4-7 switch yields traffic to the proxy server without the user noticing. Non-transparent implementation requires specific proxy server settings for each individual user's web browser.