Cutoff Value for Link Errors

The VNswitch module monitors the number of link errors that occur over its PHY port's link. The types of link errors it monitors includes, for example, line state violations. The neighbor node connected to a link is disconnected from the network if the error rate exceeds a number referred to as the cutoff value. You can set the cutoff value that triggers disconnection of a neighbor node. The value is set independently for each of the module's PHY ports. For example, the value for PHY port A is set independently of the value for PHY port B on a DAS.

If the disconnection of a neighbor node is triggered, the FDDI network establishes a loopback (wrap) onto the secondary ring at the node that initiated the disconnect. The connection is automatically reestablished when the link is again active.

Note:  Link error rate is expressed as a negative exponential value of base 10. For example, an error rate of 10-4 is equal to 0.0001 bits per second, 10-5 is equal to 0.00001 bits per second, and so on.