Limiting the lifetime of packets in computer networks

Abstract

The assurance mechanisms of end-to-end protocols used in packet-switching computer networks rely on implicit or explicit assumptions about the maximum lifetime of packets being transported from origin to destination. However, some parts of networks may hold packets for arbitrary periods but not report how long they are held. Failure in the assurance mechanisms may result. This paper describes a method to ensure that a packet is delivered only if its age does not exceed the maximum packet lifetime. The method requires knowledge of the time a packet spends on a logical link; a mechanism to measure this time can be added to existing link-level protocols. Such a mechanism is presented, along with its addition to a standard link-level protocol.