What is a Firewall? UKFast School of Hosting

Firewalls are often referred to as the “first layer of defence”, protecting your server from cyber-attacks and viruses. A firewall sits in front of your solution, filtering out malicious traffic. Although not bulletproof, they are an essential first step. Without them, online businesses would be susceptible to data loss and downtime.
Firewalls can be software, hardware or a combination of both. A software firewall runs directly on a computer, whereas physical firewalls (hardware) sit in front of the computer or server on separate hardware.

As data packets arrive at the firewall — either as they come in or go out — they are inspected and their source and destination are identified. Depending on the preconfigured access rules, the packets will then be forwarded or dropped.

Firewalls work by adhering to certain rules. They might deny all traffic unless it meets certain criteria, for example. They also allow specific external IP addresses to be blocked. UKFast customers can configure firewall rules through the MyUKFast client portal.
The internet is full of risks that necessitate the use of firewalls. As such, UKFast places all of its clients behind a fully managed shared Cisco firewall. For extra safety, a dedicated firewall, exclusively protecting one single solution instead of several, is recommended.

Duration: 1:31
Publisher: UKFast
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