Named Ipv4 Acls - Cisco Catalyst 2960 series Configuration Manual

Information About Configuring IPv4 Access Control Lists
• Internet Group Management Protocol (igmp)
• any Interior Protocol (ip)
• IP in IP tunneling (ipinip)
• KA9Q NOS-compatible IP over IP tunneling (nos)
• Open Shortest Path First routing (ospf)
• Payload Compression Protocol (pcp)
• Protocol-Independent Multicast (pim)
• Transmission Control Protocol (tcp)
• User Datagram Protocol (udp)

Named IPv4 ACLs

You can identify IPv4 ACLs with an alphanumeric string (a name) rather than a number. You can use named
ACLs to configure more IPv4 access lists in a router than if you were to use numbered access lists. If you
identify your access list with a name rather than a number, the mode and command syntax are slightly different.
However, not all commands that use IP access lists accept a named access list.
Note The name you give to a standard or extended ACL can also be a number in the supported range of access
list numbers. That is, the name of a standard IP ACL can be 1 to 99 and . The advantage of using named
ACLs instead of numbered lists is that you can delete individual entries from a named list.
Consider these guidelines before configuring named ACLs:
• Numbered ACLs are also available.
• A standard ACL and an extended ACL cannot have the same name.
• You can use standard or extended ACLs (named or numbered) in VLAN maps.
Benefits of Using the Named ACL Support for Noncontiguous Ports on an Access Control Entry Feature
The Named ACL Support for Noncontiguous Ports on an Access Control Entry feature allows you to specify
noncontiguous ports in a single access control entry, which greatly reduces the number of entries required in
an access control list when several entries have the same source address, destination address, and protocol,
but differ only in the ports.
This feature greatly reduces the number of access control entries (ACEs) required in an access control list to
handle multiple entries for the same source address, destination address, and protocol. If you maintain large
numbers of ACEs, use this feature to consolidate existing groups of access list entries wherever it is possible
and when you create new access list entries. When you configure access list entries with noncontiguous ports,
you will have fewer access list entries to maintain.
Benefits of IP Access List Entry Sequence Numbering
The ability to apply sequence numbers to IP access list entries simplifies access list changes. Prior to the IP
Access List Entry Sequence Numbering feature, there was no way to specify the position of an entry within
an access list. If a user wanted to insert an entry (statement) in the middle of an existing list, all of the entries
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
1178