- 4 - 3 Rule - Cabletron Systems SmartSTACK ETHERNET ELS10-27 User Manual

5 - 4 - 3 Rule

Table A-5. Crossover RJ45 Pin Assignments
SmartSTACK Ethernet
ELS10-27
1 (Rx+)
2 (Rx-)
3 (Tx+)
6 (Tx-)
A.6 5 - 4 - 3 RULE
Between any two nodes (i.e., PCs or other stations) on the network, there
can be:
¥ Up to Þve 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 signiÞcant for coax networks
only.
Note: This rule is completely consistent with the IEEE 802.3 specification, and
is meant only to summarize the configuration specification.
A-6
SmartSTACK Ethernet ELS10-27
3 (Tx+)
6 (Tx-)
1 (Rx+)
2 (Rx-)