One interesting problem that occurs in distributed-control, token-passing systems, is that the token may get lost. Indeed, if a token is not properly circulating around the network, no station can transmit. Comment on this problem. What safeguards can be built into a token-passing network to determine whether a token has been lost and then to restore proper operation of the network?

What will be an ideal response?

This is a manageable problem—as it must be because tokens do get lost. In any tokenpassing
scheme, each node should see the token regularly.One node could be designated as a
master to watch for the token to pass within a certain amount of time. If it does not appear,
the node could inform all other nodes that the token is lost and wait for their confirmations
that they are not holding the token. Then the master can reinsert the token. This must be
handled carefully, or multiple tokens could wind up circulating around the network.