Echo Support - Alcatel-Lucent 7210 SAS M Configuration Manual

Table 2: BFD Control Packet Field Descriptions (Continued)
Field
P Bit
F Bit
Rsvd
Detect Mult
Length
My Discriminator
Your Discriminator
Desired Min TX Interval
Required Min RX
Interval
Required Min Echo RX
Interval

Echo Support

In the BFD echo support scenario, the 7210 SAS loops back received BFD echo messages to the
original sender based on the destination IP address in the packet.
The echo function is useful when the local router does not have sufficient CPU power to handle a
periodic polling rate at a high frequency. As a result, it relies on the echo sender to send a high rate
of BFD echo messages through the receiver node, which is only processed by the receiver's
forwarding path. This allows the echo sender to send BFD echo packets at any rate.
The 7210 SAS supports only response to echo requests and does not support sending of echo
requests.
7210 SAS M, X Router Configuration Guide
The poll bit. If set, the transmitting system is requesting verification of
connectivity, or of a parameter change.
The final bit. If set, the transmitting system is responding to a received BFD control
packet that had the poll (P) bit set.
Reserved bits. These bits must be zero on transmit and ignored on receipt.
The "Detect time multiplier". In the Asynchronous mode, Detection time = Detect
time Multiplier * transmit interval. If a BFD control packet is not received from the
remote system within the detection time, implies that a failure has occurred.
Length of the BFD control packet, in bytes.
A unique, nonzero discriminator value generated by the transmitting system, used
to demultiplex multiple BFD sessions between the same pair of systems.
The discriminator received from the corresponding remote system. This field
reflects back the received value of my discriminator, or is zero if that value is
unknown.
This is the minimum interval, in microseconds, that the local system would like to
use when transmitting BFD control packets.
This is the minimum interval, in microseconds, between received BFD control
packets that this system is capable of supporting.
This is the minimum interval, in microseconds, between received BFD echo
packets that this system is capable of supporting. If this value is zero, the
transmitting system does not support the receipt of BFD echo packets.
IP Router Configuration
Description
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