Dell PowerSwitch S4820T 9.50.1 Configuration Guide for the S4820T System - Page 153
remote Desired TX Interval and the local Required Min RX Interval., Desired Min TX
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Field Description system clears the poll bit and sets the final bit in its response. The poll and final bits are used during the handshake and in Demand mode (refer to BFD Sessions). NOTE: Dell Networking OS does not currently support multi-point sessions, Demand mode, authentication, or control plane independence; these bits are always clear. Detection Multiplier The 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 packet belongs because there can be many sessions running on a single interface. Desired Min TX Interval The minimum rate at which the local system would like to send control packets to the remote system. Required Min RX Interval The minimum rate at which the local system would like to receive control packets from the remote system. Required Min Echo The minimum rate at which the local system would like to receive echo packets. RX NOTE: Dell Networking OS does not currently support the echo function. Authentication Type, Authentication Length, Authentication Data An optional method for authenticating control packets. NOTE: Dell Networking OS does not currently support the BFD authentication 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 received remote 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 own detection time. • In Asynchronous mode: Detection time is the remote Detection Multiplier multiplied by greater of the remote Desired TX Interval and the local Required Min RX Interval. • In Demand mode: Detection time is the local Detection Multiplier multiplied by the greater of the local Desired Min TX and the remote Required Min RX Interval. Bidirectional Forwarding Detection (BFD) 153
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