STANDARD Revision 1.0
C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved.
948
Chapter 33
Access Control Lists
Overview .......................................................................................... 948
Data Plane Filter IP ACLs................................................................... 950
In-band Management ....................................................................... 953
IGMP ACLs ........................................................................................ 954
IPv6 ACLs .......................................................................................... 955
Overview
An ACL, or Access Control List, is an indexed, ordered list of entries. It classifies packets based on criteria such as Source IP,
Destination IP, Application port for the IPv4 protocol type. Beginning with Release 7.3, IPv6 ACLs are supported with
entries created using the Source IP only. Each entry in the list contains a user-configured set of evaluation criteria and
either a permit or deny statement. When a packet is classified by an ACL, the fields in its header are compared one by one
with the entries in the ACL, starting with the entry with the lowest index value. When a match is found, the comparison
process is stopped and the packet is either permitted to continue or denied (dropped) according to the action specified in
the ACL.
The use of ACLs within the C4/c CMTS, and within any router for that matter, is considered a fundamental capability. ACLs
are used in conjunction with one or more ACL applications. It is the ACL application that initiates a packet classification
search in a particular ACL and takes action on the packet based on whether the matched ACL entry was a permit or deny.