The Link Estimation Exchange Protocol (LEEP)

Gnawali

sensor networking protocols routing link quality
estimation probing tiny-os

@misc{gnawali:tinyos2007,
  title={The Link Estimation Exchange Protocol {(LEEP)}},
  author={Omprakash Gnawali},
  howpublished={\url{http://www.tinyos.net/tinyos-2.x/doc/html/tep124.html}},
  publisher={{TinyOS} Network Working Group},
  month={February},
  year={2007}
}

LEEP calculates bidirectional link quality

• Other protocols ride inside LEEP frames, e.g. CTP beacons carried as LEEP payload

Every outgoing LEEP frame includes a LEEP sequence number, incremented even when retransmitted

• Nodes receiving that frame may use those sequence numbers and a small cache to determine the quality of the inbound link

Each frame also includes inbound link quality for each of the sender's neighbors

• Receiving nodes may use that (outgoing quality) combined with the inbound quality they have calculated from the neighbors' sequence numbers to determine the bidirectional quality
  • Bidirectional quality is important as unicasting relies on receiving an acknowledgment