IPv4 Access Control Lists (ACLs)

Terminology

Terminology

Access Control Entry (ACE): A policy consisting of criteria and an action (permit or deny) to execute on a packet if it meets the criteria. The elements composing the criteria include:

source IPv4 address and mask (standard and extended ACLs)

destination IPv4 address and mask (extended ACLs only)

either of the following:

all IPv4 traffic

IPv4 traffic of a specific IP protocol (extended ACLs only) (In the cases of TCP, UDP, ICMP, and IGMP, the criteria can include either all IP traffic of the protocol type or only the traffic of a specific sub-type within the protocol.)

option to log packet matches with deny ACEs

optional use of IP precedence and ToS settings (extended ACLs only)

Access Control List (ACL): A list (or set) consisting of one or more explicitly configured Access Control Entries (ACEs) and terminating with an implicit “deny” ACE. ACL types include “standard” and “extended”. See also “Standard ACL” and “Extended ACL”. To filter IPv4 traffic, apply either type:

Static Port ACL: an ACL assigned to filter inbound traffic on a specific switch port

Dynamic Port ACL: dynamic ACL assigned to a port by a RADIUS server to filter inbound traffic from an authenticated client on that port

An ACL can be configured on a port (or static trunk) as a static port ACL. (Dynamic port ACLs are configured on a RADIUS server.)

ACE: See “Access Control Entry”.

ACL: See “Access Control List”.

ACL ID: A number or alphanumeric string used to identify an ACL. A standard IPv4 ACL ID can have either an alphanumeric string or a number in the range of 1 to 99. An extended IPv4 ACL ID can have either an alphanumeric string or a number in the range of 100 to 199. See also “Identifier”.

Note: RADIUS-assigned ACLs are identified by client authentication data and do not use the ACL ID strings described here.

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