Traceback packet transport protocol
View Patent ↗Tokens identifying all of the physical routing devices, i.e., network nodes, through which a packet travels are recorded in a limited amount of space reserved in the header of the packet for such tokens. When insufficient space remains in the header of the packet for all tokens required to identify all physical routing devices through which the packet travels, sequences of multiple tokens are replaced with an abbreviation token representing the sequence. The sequence of tokens represented by an abbreviation token can also be abbreviation tokens, supporting recursive abbreviation of the token sequence in the header of the packet as needed to record the entire route of the packet through the network regardless of the limited space in the header for tracking the route of the packet.
1. A method for routing a packet through a network from a source to a destination, the method comprising:
storing data in a header of the packet to represent a complete route of the packet through the network, the data identifying at least one physical routing device of the network through which the packet travels; and
replacing data identifying at least two physical routing devices with a single token in the header of the packet such that the single token identifies the at least two physical routing devices.
2. The method of claim 1 further comprising:
storing data in the header of the packet wherein the data identifies a particular physical routing device that performs the replacing.
3. The method of claim 1 wherein the storing is performed by node logic that executes within each physical routing device that receives the packet along the route.
4. A method for identifying a particular route taken by a packet through a network, the method comprising:
retrieving one or more tokens from a header of the packet, the tokens collectively identifying one or more physical routing devices through which the packet traveled;
determining that at least a selected one of the tokens represents two or more other tokens; and
replacing the selected token with the two or more other tokens.