User's Manual

5. DigiMesh™

Introduction

XTend OEM RF Modules containing firmware version 8020 (or above) now feature DigiMesh™

mesh networking support. Mesh networking allows messages to be routed through several differ-

ent nodes to a final destination. The DigiMesh firmware allows OEMs and system integrators to

bolster their networks with the self-healing attributes of mesh networking. In the event that one

RF connection between nodes is lost (due to power-loss, environmental obstructions, etc.) critical

data can still reach its de

stination due to the mesh networking capabilities embedded inside the

modules.

A Sample DigiMesh Network Topology

DigiMesh Feature Set

XTend OEM RF Modules containing firmware version 8020 (or above) support the following fea-

tures:

 Self-healing - Any node may enter or leave the network at any time without causing the net-

work as a whole to fail.

 Peer-to-peer architecture - No hierarchy and no parent-child relationships are needed.

 Quiet Protocol - Routing overhead will be reduced by using a reactive protocol similar to

AODV. Rather than maintaining a network map, routes will be discovered and created only

when needed.

 Selective acknowledgements - Only the

destination node will reply to route requests

 Unicast and Broadcast addressing supported

 Reliable delivery - Reliable delivery of data is accomplished by means of acknowledgements.

Note that Sleep (low power) modes and encryption are not supported in this release.

Data Transmission and Routing

Unicast Addressing

When transmitting while using Unicast communications, reliable delivery of data is accomplished

using retries and acknowledgements. The number of retries is determined by the NR (Network

Retries) parameter. RF data packets are sent up to NR + 1 times and ACKs (acknowledgements)

are transmitted by the receiving node upon receipt. If a network ACK is not received within the

time it would take for a packet to traverse the network twice, a retransmission occurs.