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l |
Route
Reply can be sent by reversing the route in Route
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Request
(RREQ) only if links are guaranteed to be bi-
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directional
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u |
To
ensure this, RREQ should be forwarded only if it received on a
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link
that is known to be bi-directional
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If
unidirectional (asymmetric) links are allowed, then
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RREP
may need a route discovery for S from node D
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Unless
node D already knows a route to node S
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If a
route discovery is initiated by D for a route to S, then the
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Route
Reply is piggybacked on the Route
Request from D.
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If
IEEE 802.11 MAC is used to send data, then links have
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to be
bi-directional (since Ack is used)
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