Enterasys Networks Fast Network 10 - Manual (Page 117)

Crossover Wiring
Fast Network 10 User Guide Page A-5
A.5 CROSSOVER WIRING
Two FN10s can communicate only if the transmitter on one unit is
connected to the receiver on the other unit. This reversal, or crossover
function, can be implemented either in the wiring or in the device itself.
When connecting FN10s, a crossover must be implemented in the wiring.
Refer to Table A-3 for crossover pin assignments.
A.6 5 - 4 - 3 RULE
Between any two nodes (i.e., PCs or other stations) on the network, there
can be:
• Up to five segments in series
• Up to four repeaters or multi-port hubs
• Up to three populated segments (that is, segments attached to two or
more PCs)*
* The remaining two segments are unpopulated; these are known as
inter-repeater links or IRLs. This distinction between populated and
unpopulated segments is significant for coax networks only.
Table A-3 Crossover RJ45 Pin Assignments
FN10 FN10
1 (Tx+) 3 (Rx+)
2 (Tx-) 6 (Rx-)
3 (Rx+) 1 (Tx+)
6 (Rx-) 2 (Tx-)
NOTE
This rule is completely consistent with the IEEE 802.3
specification, and is meant only to summarize the configuration
specification.