Cabletron Systems SmartSwitch 8H02-16, Руководство пользователя

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Chapter 2: Network Requirements
2-4 8H02-16 User’s Guide
Propagation delay (collision delay) is the amount of time it takes data to
travel from the sending device to the receiving device. Total propagation
delay allowed for the entire network is 256 bit times (2.56
µ
s). If the total
propagation delay between any two nodes on the network exceeds
2.56
µ
s, then use bridges or other devices to further segment the network.
2.2 100BASE-TX NETWORK CABLE LENGTHS
This section details the maximum network cable lengths specified by the
IEEE 802.3u standard. As stated in the previous sections, the physical size
of the network is limited primarily by propagation delay. The total
propagation delay cannot exceed 256 bit times or 2.56
µ
s.
A 100BASE-TX/FX network might use all copper (UTP) links, all fiber
links or a combination of both. The maximum length of any segment is
determined by the types and combination of links and by the type of
repeater (if any) between segments. IEEE 802.3u standards specify two
repeater classes (Class 1 and Class 2) and the maximum cable lengths for
each media type.
If this device is being installed in a 100BASE-TX/FX environment with
repeaters, use the repeater instruction manual to determine the maximum
cable lengths when laying out your network.
UTP Maximum Cable Lengths
An Unshielded Twisted Pair copper segment in a 100BASE-TX
environment may be no more than 100 meters in length.
Multimode Fiber Cable Lengths
The maximum length of a 100BASE-FX segment may be no more than
412 meters between Data Terminal Equipment (DTE to DTE) in half
duplex mode or 2 km (DTE to DTE) in full duplex mode.
!
C AUT IO N
The maximum length of a UTP segment may be no more than
100 meters.