Switch Features 67
Connectivity Fault Management (IEEE 802.1ag)
The Connectivity Fault Management (CFM) feature, also known as Dot1ag, 
supports Service Level Operations, Administration, and Management 
(OAM). CFM is the OAM Protocol provision for end-to-end service layer 
instance in carrier networks. The CFM feature provides mechanisms to help 
you perform connectivity checks, fault detection, fault verification and 
isolation, and fault notification per service in a network domain. 
For information about configuring IEEE 802.1ag settings, see "Configuring 
Connectivity Fault Management" on page 761.
Cisco Protocol Filtering
The Cisco Protocol Filtering feature (also known as Link Local Protocol 
Filtering) filters Cisco protocols that should not normally be relayed by a 
bridge. The group addresses of these Cisco protocols do not fall within the 
IEEE defined range of the 802.1D MAC Bridge Filtered MAC Group 
Addresses (01-80-C2-00-00-00 to 01-80-C2-00-00-0F).
For information about configuring LLPF, settings see "Configuring Port-
Based Traffic Control" on page 687.
DHCP Layer 2 Relay
This feature permits Layer 3 Relay agent functionality in Layer 2 switched 
networks. The switch supports L2 DHCP relay configuration on individual 
ports, link aggregation groups (LAGs) and VLANs. 
For information about configuring L2 DHCP Relay settings see "Configuring 
L2 and L3 Relay Features" on page 907.