About Autonegotiation
continued
Startup communication between the two devices occurs when
both devices are operating, the cable connection between
them is good, and the connected notebook PC's network soft-
ware is loaded. As soon as those conditions are satisfied,
the preparatory process of auto-negotiation between the
DFE-670TXD and its supporting device begins and proceeds
automatically.
If the supporting switch or hub has autonegotiation functional-
ity, then it and the DFE-670TXD exchange a series of
messages in which each device signals its capabilities and
listens for corresponding information about the other. The
auto-negotiation process requires only a few milliseconds,
and the two devices select the best communication parame-
ters supported by both devices.
If the supporting device does not have autonegotiation func-
tionality, then its monotone (single capability) message will be
recognized by the DFE-670TXD's autonegotiation facility, and
the DFE-670TXD will simply switch to the one of its own
capabilities which matches that of the supporting device.
Once the auto-negotiation is completed, the line is ready, and
it will provide an optimal data channel between the DFE-
670TXD and the supporting device. The line will remain
ready without further auto-negotiation action until the link is
broken. Auto-negotiation then reoccurs at any time that the
link is restored, again making the line ready for optimal data
communications.
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