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tjsalo
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Iron
Re: Dec 5 - DAY 3: 802.15.4 Radio Protocols & Topology
tjsalo   12/5/2012 2:52:42 PM
NO RATINGS
Regarding use of Zigbee in a 100 km network:

Zigbee is a suite of protocols.  Some protocols may have more problems with the propagation delay of such a network, while other protocols might work OK.

I suspect that the CSMA-CA protocol (if you are really using that on each hop) seems likely to perform poorly.  This is analogous to the maximum size of an Ethernet network, which is limited by propagation delay.

The ack mechanism probably works poorly, because of the long delay between a packet transmission and the reception of the ack.

The limitation of having only one outstanding (unacknowledged) frame at a time is a problem with a network this large.



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