LINK ESTIMATION EXCHANGE PROTOCOL: (LEEP)

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In-bound link quality:In-bound link quality is a value in the range of 0 to 255 that descries the quality of link from A to B estimated by B by counting the packets which are successfully receuved among all the transmitted packets.

For calculating the bidirectional link quality ,the in-bound link should be exchanged among the neighbours.LEEP frame includes a sequence number that will be incremented for every outbound.It will be incremented even when it is retransmitted. Nodes receiving the frames use those sequence numbers and a small cache to determine the quality of in-bound link. Each frame also includes inbound link quality for each of the sender's neighbours.
Receiving nodes may use that (outbound quality) combined with the inbound quality that they have calculated from the neighbour's sequence numbers to determine the bidirectional quality.

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