Certainly! Here's an example of a simple packet filtering firewall rule that allows or blocks traffic based on source and destination IP addresses and port numbers. This rule is written in a common format and can be used on various packet filtering firewalls:
Rule: Allow inbound web traffic to a web server on port 80.
Rule Description: This rule allows incoming HTTP (web) traffic to reach a web server on the internal network. It is a common rule used to enable access to a website hosted on the web server.
Direction: Inbound (from external to internal network)
Action: Allow
Protocol: TCP (Transmission Control Protocol)
Source IP Address: Any (0.0.0.0/0) - This means traffic can come from any source IP address.
Destination IP Address: The IP address of the web server (e.g., 192.168.1.100)
Source Port: Any (0-65535) - Any source port on the external side.
Destination Port: 80 - The standard port for HTTP traffic.
In this rule, any incoming traffic with a source IP address from the external network (e.g., the internet) to the specified destination IP address on port 80 (HTTP) will be allowed. This enables users to access the web server hosted on the internal network.
Keep in mind that this is a basic example. In a real-world scenario, firewall rules can become more complex, incorporating additional conditions and actions to provide comprehensive security and meet specific network requirements.
