Patent ID: 7668204

Claim:
A method for authenticating a message in a time division multiple access network, the method comprising: receiving a message having a designated field from a node at an active relaying component; inserting a unique identifier into the designated field of the message at the active relaying component; forwarding the message on to at least one other node in the network; authenticating the message at the at least one other node based, at least in part, on the designated field; and analyzing the message at the at least one other node to detect passive behavior of the active relaying component; wherein the designated field is included in an error detection mechanism of the message received at the active relaying component and authenticating the message comprises calculating, at the at least one other node, an error detection mechanism which includes the designated field; and wherein detecting passive behavior comprises detecting one of a short circuit in the active relaying component or a bypass around the active relaying component by absence of a change in the unique identifier.