CTC Union ET100A, Руководство пользователя

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ET100A LAN-WAN Bridge
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LAN Flow Control:
The
ET100A
LAN port supports IEEE802.3x flow control, which can
help to regulate the higher speed LAN traffic that hits the bottle neck of
the slower WAN speed. Without flow control, the LAN packets that exceed
the WAN speed will be dropped and the resulting timeout caused must be
handled by the application layer.
LAN Auto Negotiation:
The
ET100A
LAN port supports auto ‐ negotiation per IEEE802.3u.
When auto negotiation is enabled and the LAN port connects to another
auto negotiation compliant port, the LAN speed will be auto detected
while the Duplex should be negotiated to Full Duplex.
When connecting to legacy equipment, it may be necessary to 'force'
the speed and Duplex on the LAN port. Care must be taken here to avoid a
Duplex Mismatch condition when a 'forced' port connects to an 'auto' port.
Without negotiation, an 'auto' port will revert to Half Duplex per the
IEEE802.3u standard. A Duplex Mismatch condition could result in
extremely poor network performance.
WAN Interface Selection:
The ET100A has selectable hardware interface circuits. When set to
X.21/RS ‐ 530/RS ‐ 449, the logic, clock and handshaking signals all follow
RS ‐ 422 electrical (balanced signals). When set to RS ‐ 232, all signals
become single ended and follow RS ‐ 232D signal levels. When configured as
V.35, the logic and clock signals follow RS ‐ 422 electrical, while handshaking
signals are RS ‐ 232 electrical.