Cabletron Systems 42T User Manual
REQUIREMENTS/SPECIFICATIONS
2-5
cable length for ring speeds of 4 and 16 Mbps. The cable lengths listed in
Table 2-4 refer to total lengths made up of STP cable only
Table 2-4 refer to total lengths made up of STP cable only
.
Maximum Trunk Lengths
The maximum trunk cable length between the MicroMMAC-T and other
active devices is equal to the maximum drive distance as shown in
Table 2-5. For passive devices, the combined length of twice the longest
trunk cable, plus the longest lobe cable attached to the passive ring
segment cannot exceed the Maximum Drive Distance.
active devices is equal to the maximum drive distance as shown in
Table 2-5. For passive devices, the combined length of twice the longest
trunk cable, plus the longest lobe cable attached to the passive ring
segment cannot exceed the Maximum Drive Distance.
Maximum Number of Stations
If only STP lobe cabling is used throughout the ring, the MicroMMAC-T
supports up to 255 ring stations, regardless of ring speed.
supports up to 255 ring stations, regardless of ring speed.
Table 2-4. STP Maximum Lobe Lengths
STP Cable Type
Ring Speed
4 Mbps
16 Mbps
IBM Types 1 & 2
300 meters
150 meters
(984 feet)
(492 feet)
IBM Types 6 & 9 (only for
station to wall jack and patch
panels)
station to wall jack and patch
panels)
30 meters
30 meters
(99 feet)
(99 feet)
Table 2-5. STP Maximum Drive Distance
STP Cable Type
Ring Speed
4 Mbps
16 Mbps
IBM Types 1 & 2
770 meters
346 meters
(2525 feet)
(1138 feet)
IBM Types 6 & 9
513 meters
230 meters
(1683 feet)
(755 feet)