Cabletron Systems BRIM-T6 用户手册

MEDIA SPECIFICATIONS AND REQUIREMENTS

B-3

Maximum Lobe Length

Lobe length is the physical length of the cable connecting a station to its
TCU port. Table B-3 shows maximum lobe length according to ring speed.
The length figures are for total lengths of STP cable only.

Maximum Trunk Lengths

The maximum trunk cable length between active devices is equal to the
maximum drive distance. When the neighboring device is passive, the
Maximum Drive Distance must not exceed the combined length of twice
the longest trunk cable plus the longest lobe cable attached to the passive
ring segment (see Table B-3).

NOTE: IBM Types 6 & 9 are to be used only for lobe connections from
station to wall jack and patch panels.

B.3 UNSHIELDED TWISTED PAIR (UTP)

TPIM-T2 supports voice-grade UTP cable (as described in EIA/TIA TSB
568) and IBM Type 3 cable.

WARNING: Do not connect UTP cabling to any non-Token Ring network
conductors (telephone, etc.) or ground. If in doubt, test wiring before
using. Telephone battery and ringing voltages used in UTP telephone
circuits may present a shock hazard and may damage Token Ring
equipment when connected to token ring cabling.

Table B-3. STP Maximum Lengths

IBM
Type

Max. Lobe Length

Max. Drive Distance

4 Mbps

16 Mbps

4 Mbps

16 Mbps

1 & 2

200 meters
(660 feet)

100 meters
(300 feet)

770 meters
(2525 feet)

346 meters
(1138 feet)

6 & 9

30 meters
(99 feet)

513 meters
(1683 feet)

230 meters
(755 feet)