Chapter 1
Product Overview
Cisco Discovery Protocol
The Cisco Discovery Protocol (CDP) is a device-discovery protocol that is both media- and
protocol-independent. CDP is available on all Cisco products, including routers, switches, bridges, and
access servers. Using CDP, a device can advertise its existence to other devices and receive information
about other devices on the same LAN. CDP enables Cisco switches and routers to exchange information,
such as their MAC addresses, IP addresses, and outgoing interfaces. CDP runs over the data-link layer
only, allowing two systems that support different network-layer protocols to learn about each other. Each
device configured for CDP sends periodic messages to a multicast address. Each device advertises at
least one address at which it can receive Simple Network Management Protocol (SNMP) messages.
For information on configuring CDP, see
Cisco Group Management Protocol (CGMP) server
CGMP server manages multicast traffic. Multicast traffic is forwarded only to ports with attached hosts
that request the multicast traffic.
EtherChannel Bundles
EtherChannel port bundles allow you to create high-bandwidth connections between two switches by
grouping multiple ports into a single logical transmission path.
For information on configuring EtherChannel, see
State Tracking."
Ethernet CFM
Ethernet CFM is an end-to-end per-service-instance (per-VLAN) Ethernet layer OAM protocol that
includes proactive connectivity monitoring, fault verification, and fault isolation. End-to-end can be
provider-edge-to provider-edge (PE-to-PE) device or customer-edge-to-customer-edge (CE-to-CE)
device. Ethernet CFM, as specified by IEEE 802.1ag, is the standard for Layer 2 ping, Layer 2 traceroute,
and end-to-end connectivity check of the Ethernet network.
For information about CFM, see
Ethernet OAM Protocol
Ethernet Operations, Administration, and Maintenance (OAM) is a protocol for installing, monitoring,
and troubleshooting Ethernet networks to increase management capability within the context of the
overall Ethernet infrastructure. You can implement Ethernet OAM on any full-duplex, point-to-point, or
emulated point-to-point Ethernet link for a network or part of a network (specified interfaces).
For information about OAM, see
OL-25340-01
Chapter 28, "Configuring CDP."
Chapter 24, "Configuring EtherChannel and Link
Chapter 63, "Configuring Ethernet OAM and CFM."
Chapter 63, "Configuring Ethernet OAM and CFM."
Software Configuration Guide—Release IOS XE 3.3.0SG and IOS 15.1(1)SG
Layer 2 Software Features
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