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GS752TP, GS728TP, and GS728TPP Gigabit Smart Switches
Access Control Lists (ACLs)
ACLs ensure that only authorized users have access to specific resources while blocking off
any unwarranted attempts to reach network resources.
ACLs are used to provide traffic flow control, restrict contents of routing updates, decide
which types of traffic are forwarded or blocked, and provide security for the network. ACLs
are normally used in firewall routers that are positioned between the internal network and an
external network, such as the Internet. They can also be used on a router positioned between
two parts of the network to control the traffic entering or exiting a specific part of the internal
network. The added packet processing required by the ACL feature does not affect switch
performance. That is, ACL processing occurs at wire speed.
Access lists are a sequential collection of permit and deny conditions. This collection of
conditions, known as the filtering criteria, is applied to each packet that is processed by the
switch or the router. The forwarding or dropping of a packet is based on whether the packet
matches the specified criteria.
Traffic filtering requires the following two basic steps:
1. Create an access list definition.
The access list definition includes rules that specify whether traffic matching the criteria is
forwarded normally or discarded. Additionally, you can assign traffic that matches the
criteria to a particular queue or redirect the traffic to a particular port. A default denies all
rule is the last rule of every list.
2. Apply the access list to an interface in the inbound direction.
The switch enables ACLs to be bound to physical ports and LAGs.The switch software
supports MAC ACLs and IP ACLs.

Sample MAC ACL Configuration

The following example shows how to create a MAC-based ACL that permits Ethernet traffic
from the Sales department on specified ports and denies all other traffic on those ports.
1. In the MAC ACL screen, create an ACL with the name Sales_ACL for the Sales
department of your network.
For more informations, see MAC ACL on page 190.
By default, this ACL is bound on the inbound direction, which means the switch examines
traffic as it enters the port.
2. In the MAC Rules screen, create a rule for the Sales_ACL with the following settings:
•ID. 1
•Action. Permit
•Match Every. False
•CoS. 0