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IPv6 Access List Commands
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IPv6 Access List Commands
Access to a switch or router can be made more secure through the use of 
Access Control Lists (ACLs) to control the type of traffic allowed into or out 
of specific ports. An ACL consists of a series of rules, each of which describes 
the type of traffic to be processed and the actions to take for packets that 
meet the classification criteria. Rules within an ACL are evaluated 
sequentially until a match is found, if any. Every ACL is terminated by an 
implicit deny all rule, which covers any packet not matching a preceding 
explicit rule. ACLs can help to ensure that only authorized users have access 
to specific resources while blocking out any unwarranted attempts to reach 
network resources.
ACLs may be used to restrict contents of routing updates, decide which types 
of traffic are forwarded or blocked and, above all, 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 PowerConnect ACL feature allows classification of packets based upon 
Layer 2 through Layer 4 header information. An Ethernet IPv6 packet is 
distinguished from an IPv4 packet by its unique Ethertype value; thus all IPv6 
classifiers include the Ethertype field.
Multiple ACLs per interface are supported. The ACLs can be combination of 
Layer 2 and/or Layer 3/4 ACLs. ACL assignment is appropriate for both 
physical ports and LAGs. ACLs can also be time based.
Commands in this Chapter
This chapter explains the following commands:
2CSPC4.X8100-SWUM102.book  Page 511  Friday, March 15, 2013  8:56 AM