A proxy server on network can be useful regarding security. Proxy servers can also act as a cache that enables users to get faster internet access. At the same time, this server allows them to share downloads more easily. Squid is a web proxy server that is secure and it has good caching facilities too. In computers based on Ubuntu operating systems, this Proxy server can be installed. This can be done by entering the required commands in the terminal of Ubuntu. It is also important to configure the proxy server after the installation process is completed.
To install Squid type the following command in a terminal:
sudo aptitude install squid
2.Configuring the proxy
Configuration of Squid is done by editing the following file: /etc/squid/squid.conf To edit this file, type Alt+F2 and enter the following command:
gksu gedit /etc/squid/squid.conf
2.1.Naming the proxy
Its important that Squid knows the name of the machine. To do this, locate the line visible_hostname.
For example, if the machine is called ubuntu insert:
2.2 Choosing the Port
By default, the proxy server will use port 3128. To choose another port, locate the line:
and change the port number, for example:
2.3.Choosing the interface
By default the proxy server will listen on all interfaces. For security reasons, its better to put it on your local network only. For example, if the network card connected to your LAN has IP 10.0.0.1, change the line:
2.4. Setting access rights and priorities
By default, nobody else is allowed to connect to the proxy server. A list of permissions must be created.
For example, we will define a group encompassing the local network.
Find the line beginning with acl localhost... At the end of the section, add:
acl lanhome src 10.0.0.0/255.255.255.0
(lanhome is a random name chosen).
2.5. Authorizing access to group
Now that the group is defined, we will authorise it to use the proxy.
Locate the line http_access allow ... and add below (before the line http_access deny all):
http_access allow lanhome
2.6. Allow the use non-standard ports
By default, Squid allows HTTP traffic only on specific ports (e.g. 80). This can cause problems on websites using other ports.