How to control internet access on a network using a server?

Internet access is a privilege, not a right. This means that if you are running your own network, it’s up to you how you want people to gain access. But this also means that you need to take the responsibility of limiting their access into account when designing your network and configuring its security measures. Let us introduce the different ways in which internet users can be controlled on a network by using server software!

Things to know before setting up internet access control:

When setting up a network it is important to consider the security features you want. There are several ways in which internet access can be controlled, and where there is control, there will always be hackers trying to get around these restrictions! Some of them may even try to hijack your server software so they can have free or unlimited access online, but you can prevent these kinds of attacks by using one of the methods below.

Best Ways to control internet access on a network:

There are plenty of other ways to control access to your network. These are some basic ones that you can choose from depending on what works best for your situation and the company’s needs.

First, you can use a Proxy server – this is basically just another device that sits between the internet and your network. A proxy works by sending all requests from the internal network to a proxy server which in turn contacts the real internet. The proxy will then return all results back to your internal machines, so you can control what sites are visited. The proxy server will also keep track of all activity for reporting purposes which you might find useful if you wish to ban certain websites.
Second, you can use a Firewall to control internet access. A firewall is basically just an appliance that will filter the traffic moving in and out of the network. Firewalls can be either software or hardware-based and require some configuration to allow certain connections while blocking unwanted ones.
Third, you can put your network behind a VPN which will encrypt all the traffic on your internal network while sending it to an external server. VPN is a more secure option, so if you are worried about your company’s data being stolen or leaked this might be the way to go.
Finally, you can use a proxy server combined with a VPN for the ultimate security and control over your network’s internet access!

Control internet access using a Squid proxy server

First of all, you will need a proxy server to control internet access. If you already have one in place that is great! if not, then the next step would be to deploy such software on your network (for example – Squid or Privoxy).
You will need to tell your proxy server which websites it should allow or not, so go ahead and create a white list of allowed domains in the /etc/squid/squid.conf file!
By default Squid allows only domain names (not IP addresses) so you can leave this field empty if you wish – but it’s a good idea to put some top-level domains that you know everyone will need access to, like for example com; net; org and so on.
Finally, restart your proxy server service (Squid/Privoxy) by issuing the command sudo systemctl restart squid or whatever other name it might have if not called exactly that.

Control internet access using a firewall on a Linux server?

If you already have a firewall in place that is great! If not, then the next step would be to deploy such software on your network (for example – Iptables).
Next up, configure your new firewall and make sure it is active at startup by enabling it so any time the server gets restarted it should be started with that. You will need to tell your firewall which websites it should allow or not, so go ahead and create a white list of allowed domains in the /etc/sysconfig/iptables file!
Finally, restart your firewall service (Iptables) by issuing the command sudo systemctl restart iptables or whatever other name it might have if not called exactly that.

Control internet access by using OpenVPN?

If you already have a VPN in place that is great! If not, then the next step would be to deploy such software on your network (for example – OpenVPN).
Next up, configure your new VPN and make sure it is active at startup by checking the status of that service. You will need to tell your firewall which websites it should allow or not, so go ahead and create a white list of allowed domains in the /etc/openvpn/server.conf file!
Finally, restart your VPN service (OpenVPN) by issuing the command sudo systemctl restart openvpn or whatever other name it might have if not called exactly that.

Conclusion:

Controlling internet access is a very important task for network administrators. This article has explained how you can control internet access on a network using three different methods: creating an iptables firewall, installing and configuring OpenVPN, or by using a Squid proxy server.