Rule - Allied Telesis AT-MR420TR Installation Manual

5 - 4 - 3 Rule

In addition to the requirements outlined in Chapter 3, Table 2, follow
the "5-4-3 rule" to ensure that your configuration does not exceed the
maximum 10Base-T data transmission path (the longest path through
any given network).
The 5-4-3 rule describes the maximum path between any two devices
or nodes (PCs or other stations) on the network. There can be:
Up to five segments in series
Up to four repeaters or multiport 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.
This rule is completely consistent with the IEEE 802.3
specification, and is meant only to summarize the
configuration specification.
AT-MR420TR and AT-MR820TR Installation Guide
Note
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