Table of Contents
Advertisement
Chapter 15 ACL Configuration
15.1 Introduction to ACL
ACL (Access Control List) is an IP packet filtering mechanism employed in switches,
providing network traffic control by granting or denying access through the switches,
effectively safeguarding the security of networks. The user can lay down a set of rules
according to some information specific to packets, each rule describes the action for a
packet with certain information matched: 'permit' or 'deny'. The user can apply such rules
to the incoming or outgoing direction of switch ports, so that data streams in the specific
direction of specified ports must comply with the ACL rules assigned.
15.2 Access-list
Access-list is a sequential collection of conditions that corresponds to a specific rule.
Each rule consists of filter information and the action when the rule is matched.
Information included in a rule is the effective combination of conditions such as source IP,
destination IP, IP protocol number and TCP port. Access-lists can be categorized by the
following criteria:
Filter information based criterion: IP access-list (layer 3 or higher information),
MAC access-list (layer 2 information), and MAC-IP access-list (layer 2 or layer 3
or higher).
Configuration complexity based criterion: standard and extended, the extended
mode allows more specific filtering of information.
Nomenclature based criterion: numbered and named
Description of an ACL should cover the above three aspects.
15.2.1 Access-group
When a set of access-lists are created, they can be applied to traffic of any direction
on all ports. Access-group is the description to the binding of an access-list to the
specified direction on a specific port. When an access-group is created, all packets from in
the specified direction through the port will be compared to the access-list rule to decide
whether to permit or deny access.
15.2.2 Access-list Action and Global Default Action
There are two access-list actions and default actions: 'permit' or 'deny'
DCS-3950 series Ethernet switch manual
249
Hide quick links:
Advertisement
Table of Contents
Troubleshooting
