Cabletron Systems 9T428-16 - Manual (Page 22)

Installation
2-8
Figure 2-6. Connecting Fiber Optic cable to the 9T428-16
Recommended Cable Lengths
The IEEE 802.5 speciÞcation does not specify a minimum lobe length in meters
that a Token Ring station must meet. Rather the standard speciÞes Cable
Attenuation, Signal to Crosstalk Noise Ratio (SCNR) and a Next Loss to Insertion
Loss Ratio (NIR) which must be met. This method of speciÞcation allows
maximum ßexibility when constructing a cabling system, however it can be very
complicated to the end user unfamiliar with these terms.
Therefore the following cabling guidelines are recommended. These
recommendations are conservative to provide a problem free environment to the
end user. Longer lengths are achievable with good cable plants.
Table 2-3 and Table 2-4 list the recommended cable lengths for Station cables.
Table 2-5 lists the recommended cable lengths for Lobe cables.
To TX Port on Other Ring
To RX Port on Other Ring
TX Port
RX Port