Cabletron Systems Spectrum 2E42-27, User Manual

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Chapter 2: Network Requirements
2-2 2E42-27/2E42-27R/2E43-27/2E43-27R User’s Guide
2.3 100BASE-TX NETWORK
The 2E4X-27, with an FE-100TX installed in ports 25 and 26, provides
an RJ45 connection that supports UTP cabling, which has an impedance
of 85 to 111 ohms. The device at the other end of the twisted pair segment
must meet IEEE 802.3u 100BASE-TX Fast Ethernet network
requirements for the devices to operate at 100 Mbps. Refer to the
Cabletron Systems Cabling Guide for details.
2.4 100BASE-FX FIBER OPTIC NETWORK
Ports 25 and 26 of the 2E4X-27 support the Cabletron Systems
FE-100FX and FE-100F3 fiber optic interface modules. The device at the
other end of the fiber optic segment must meet the 100BASE-FX Fast
Ethernet network requirements to operate at 100 Mbps. Refer to the
Cabletron Systems Cabling Guide for details.
Multimode Mode Fiber Optic Cable Length
The maximum multimode fiber optic cable length of a 100BASE-FX
segment is covered in the Cabletron Systems Cabling Guide.
Single Mode Fiber Cable Lengths
The maximum single mode fiber optic length of a 100BASE-FX segment
may be no more than 5 km between Data Terminal Equipment (DTE to
DTE) in half duplex mode or 20 km (DTE to DTE) in full duplex mode.
NOTE
The 2E4X-27 with an FE-100TX installed is capable of
operating at either 10 or 100 Mbps. The FE-100TX can
automatically sense the speed of the other device and adjusts
its speed accordingly.