Classification of ACL \ x0d \ x0d \ At present, there are two main types of ACL: standard ACL and extended ACL. \x0d\ \x0d\ The difference between the two ACLs is that the standard ACL only checks the source address of the packet; The extended ACL not only checks the source address of the packet, but also the destination address of the packet, and can also check the specific protocol type and port number of the packet. \x0d\ \x0d\ Network administrators can use standard ACL to block all traffic from a specific network, or allow all traffic from a specific network, or deny all traffic from a specific protocol group (such as IP). \x0d\ \x0d\ Extended ACL provides a wider control range than standard ACL. For example, if a network administrator wants to "allow foreign Web traffic to pass and reject foreign communication traffic such as FTP and Telnet", he can use extended ACL to achieve his goal, but standard ACL can't achieve such precise control. \x0d\ \x0d\ In router configuration, the difference between standard ACL and extended ACL is reflected by the table number of ACL. The table above shows the range of legal table numbers allowed by each protocol. \x0d\ I hope it helps you a little. \x0d\□