Which attributes can be used in advanced ACL rules to describe IP packets?

Advanced ACL (Access Control List) rules are designed to provide fine-grained control over network traffic by allowing configurations based on multiple attributes of IP packets. One of the unique attributes that can be utilized in advanced ACL rules is the ICMP packet type and message code.

ICMP (Internet Control Message Protocol) is a protocol used predominantly for sending error messages about network operations. When creating ACLs, it’s crucial to differentiate between different ICMP messages to effectively allow or block traffic meant for network management and error reporting. For instance, you may want to allow certain ICMP messages, like echo requests (ping), while blocking others, like destination unreachable messages.

While source IP address, destination IP address, and port number are fundamental elements in filtering IP traffic and are commonly used in basic ACLs, they do not encompass the complete range of controls offered by advanced ACL configurations. Advanced ACLs leverage the specificity of ICMP attributes to manage IP traffic most effectively, particularly in scenarios involving diagnostics and troubleshooting within a network context.