Cisco Systems 7600 Series Manual De Usuario

This chapter contains network security information unique to the Cisco 7600 series routers, which 
supplements the network security information and procedures in these publications:

Cisco IOS Security Configuration Guide, Release 12.1, at this URL:

Cisco IOS Security Command Reference, Release 12.1, at this URL:

This chapter consists of these sections:

With Releases 12.1(11b)E and later releases, when you are in configuration mode you can enter EXEC 
mode-level commands by entering the do keyword before the EXEC mode-level command.

The following guidelines apply to ACL configurations:

Each type of ACL (IP, IPX, and MAC) filters only traffic of the corresponding type. A MAC ACL 
never matches IP or IPX traffic.

By default, the MSFC sends Internet Control Message Protocol (ICMP) unreachable messages when 
a packet is denied by an access group.