Passive Mode And Active Mode; Lacp Functions; Lacp Parameters; Lacp Usage Scenarios - Cisco ONS 15454 SDH Configuration Manual

Chapter 10 Configuring Link Aggregation

Passive Mode and Active Mode

LACP operates in two modes: active and passive mode. In the active mode, LACP packets are transmitted
unconditionally. Whereas, in passive mode LACP starts transmitting packets only after it receives a
LACP packet from the peer device.

LACP Functions

LACP performs the following functions in the system:
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In addition, LACP provides the following benefits:
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LACP Parameters

LACP utilizes the following parameters to control aggregation:
System Identifier—A unique identification assigned to each system. It is the concatenation of the system
priority and a globally administered individual MAC address.
Port Identification—A unique identifier for each physical port in the system. It is the concatenation of
the port priority and the port number.
Port Capability Identification—An integer, called a key, that identifies one port's capability to aggregate
with another port. There are two types of key: administrative and operational. An administrative key is
configured by the network administrator, and an operational key is assigned by LACP to a port based on
its aggregation capability.
Aggregation Identifier—A unique integer that is assigned to each aggregator and is used for
identification within the system.

LACP Usage Scenarios

In Software Release 8.0.0 and later, LACP functions on ML-Series cards in termination mode and on the
CE-Series cards in transparent mode.

Termination Mode

In termination mode, the link aggregation bundle terminates or originates at the ML card. To operate in
this mode, LACP should be configured on the Ethernet interface. One protect SONET or SDH circuit
can carry the aggregated Ethernet traffic of the bundle. The advantage of termination mode over
Maintains configuration information in order to control aggregation
Exchanges configuration information with other peer devices
Attaches or detaches ports from the link aggregation group based on the exchanged configuration
information
Enables data flow when both sides of the aggregation group are synchronized
Logical aggregation of bandwidth
Load balancing
Fault tolerance
Cisco ONS 15454 and Cisco ONS 15454 SDH Ethernet Card Software Feature and Configuration Guide, R8.0
Passive Mode and Active Mode
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