Cabletron Systems 8H02-16 manual 100BASE-TX Network Cable Lengths

Chapter 2: Network Requirements

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 ∝s). If the total propagation delay between any two nodes on the network exceeds

2.56 ∝s, then use bridges or other devices to further segment the network.

2.2100BASE-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 ∝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.

The maximum length of a UTP segment may be no more than

!100 meters.

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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.

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