Field Descriptionsystem clears the poll bit and sets the final bit in its response. The poll and final bits areused during the handshake and in Demand mode (refer to BFD Sessions).NOTE: The Dell Networking OS does not currently support multi-point sessions,Demand mode, authentication, or control plane independence; these bits arealways clear.DetectionMultiplierThe number of packets that must be missed in order to declare a session down.Length The entire length of the BFD packet.My Discriminator A random number generated by the local system to identify the session.Your Discriminator A random number generated by the remote system to identify the session.Discriminator values are necessary to identify the session to which a control packetbelongs because there can be many sessions running on a single interface.Desired Min TXIntervalThe minimum rate at which the local system would like to send control packets to theremote system.Required Min RXIntervalThe minimum rate at which the local system would like to receive control packets fromthe remote system.Required Min EchoRXThe minimum rate at which the local system would like to receive echo packets.NOTE: The Dell Networking OS does not currently support the echo function.AuthenticationType,AuthenticationLength,AuthenticationDataAn optional method for authenticating control packets.NOTE: The Dell Networking OS does not currently support the BFDauthentication function.Two important parameters are calculated using the values contained in the control packet.Transmit interval Transmit interval is the agreed-upon rate at which a system sends control packets.Each system has its own transmit interval, which is the greater of the last receivedremote Desired TX Interval and the local Required Min RX Interval.Detection time Detection time is the amount of time that a system does not receive a control packet,after which the system determines that the session has failed. Each system has its owndetection time.• In Asynchronous mode: Detection time is the remote Detection Multipliermultiplied by greater of the remote Desired TX Interval and the local Required MinRX Interval.• In Demand mode: Detection time is the local Detection Multiplier multiplied bythe greater of the local Desired Min TX and the remote Required Min RX Interval.Bidirectional Forwarding Detection (BFD) 167
