Allied Telesis AT-MR912TX - Manual (Page 40)

Installation
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7. Check the front panels to make sure the green power (PWR) LEDs are
illuminated.
8. As Figure 13 on page 18 illustrates, Port 12 (MDI) of the bottom hub is
connected to Port 11 on the upper hub in the cascaded sequence.
9. Plug all Category 5 STP/UTP cables into the 100Base-TX network ports
(RJ-45 connectors) on the front of the units.
10. Plug the opposite end of each 100Base-TX cable into a network node or
workstation as appropriate.
Collision Domain Diameters
A summary of the Collision Domain Diameters for 802.3u is shown in Table 8:
Table 8: 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 connection 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 overall Collision Domain Diameter does not exceed 205
meters.
You are now ready to operate your AT-MR912TX 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