Patent ID: 7903544

Claim:
A communication node, comprising: a network interface to a freespace optical communication link; a control processor coupled to said network interface and configured to monitor transmission of data over said freespace optical communication link; wherein said communication node is configured to disable transmission of data over said freespace optical communication link in response to detecting that a failure of said communication link lasts for a period of time longer than a first configurable timeout threshold associated with a first level of the communication link, wherein the first configurable timeout threshold is changeable; and wherein the communication node is configured to disable transmission of data over said freespace optical communication link in response to detecting that a failure of said communication link lasts for a period of time longer than a second configurable timeout threshold associated with a second, different level of the communication link, wherein the second configurable timeout threshold is changeable, wherein said detecting that a failure of said communication link lasts for a period of time longer than a second configurable threshold includes detecting that data is received from an incorrect source.