Table 5: collision domain diameters per ieee stand, Dte to dte, 100m – Allied Telesis AT-MR908TX User Manual
Page 34: 412m, 1 class i repeater, 200m, 272m, 231m, 1 class ii repeater, 320m

Installation
14
Collision Domain Diameters
A summary of the collision Domain Diameters is in Table 5:
Table 5: Collision Domain Diameters per IEEE Standard 802.3u
Note
The Collision Domain Diameter for a Class II repeater cannot exceed
205 meters. That is, the hub-to-device connection should never be
more than 100 meters and the inter-repeater should be 5 meters
(Note, however, that this inter-repeater link can be greater if all
device-to-repeater links are shortened. You simply have to ensure
that the Collision Domain Diameter remains at 205 meters.)
You are now ready to operate your AT-MR908TX hubs in a cascaded hub
configuration.
Model
All Copper
All Fiber
T4 and
Fiber
TX and
Fiber
DTE to DTE
100m
412m
na
na
1 Class I Repeater
200m
272m
231m*
260.8m*
1 Class II Repeater
200m
320m
304m*
308.8m*
2 Class II repeaters
205m
228m
236.3m**
216.2m**
*Assumes 100m of copper + one fiber link
**Assumes 105m of copper + one fiber link