To setup authentication, first we need to download the package apache2 (Debian). First, we need to create a file that would contain the username and passwords of users who are allowed access. Step 1: #apt-get install apache2 Step 2 : #vim /etc/squid/password_file Now, the file ownership must be changed as owner: root and group: proxy #chown root:proxy /etc/squid/password_file #chmod 640 /etc/squid/password_file Step 3 : Create the users: #htpasswd /etc/squid/passwd username Step 4: #/etc/squid/squid.conf acl localhost src 127.0.0.1/32 acl to_localhost dst 127.0.0.0/8 acl bol_network src 192.168.200.0/24 acl login proxy_auth REQUIRED ### Edit This line http_access allow bol_network login ### Edit This line http_access deny all edit: auth_param basic program /usr/lib/squid/ncsa_auth /etc/squid/passwd The following lines should be...