About Fast Ethernet
Fast Ethernet is a network technology specified by IEEE Standard
802.3u. It extends the traditional 10Mbps (10 megabit/sec)
Ethernet technology to achieve 100Mbps (100 megabit/sec) trans-
mission and reception. Because Fast Ethernet retains the tradi-
tional Ethernet CSMA/CD (Carrier Sense, Multiple Access,
Collision Detect) protocol, it remains wholly compatible with
10Mbps Ethernet while providing a tenfold increase in network
capacity.
The Fast Ethernet standard specifies three subtypes, correspon-
ding to three media types:
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100Base-TX (using two twisted pairs in EIA 568 Category 5
UTP or STP cable)
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100Base-T4 (using four twisted pairs in a Category 3,
Category 4, or Category 5 UTP cable)
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100Base-FX (using two fiber-optic strands.)
The DFE-670TXD provides full-duplex and half-duplex 100Base-
TX operation (in Category 5 twisted-pair cable environments). It
does not provide 100Base-T4 or 100Base-FX operation. To pro-
vide for traditional 10Mbps Ethernet operation in twisted-pair cable
environments, the DFE-670TXD also offers 10Mbps Ethernet oper-
ation, in full-duplex and half-duplex modes. The DFE-670TXD's
autonegotiation capability provides for automatic selection of the
best operation mode.
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