3Com 5104M-FL1 installation and operation guide Connecting External Network Devices

To determine if the network configuration in Figure 2-8 is legal:

1.Use 4200 meters as the maximum network diameter as defined by the 802.3 specification.

2.Subtract the equivalent fiber distance for each 10BASE-FL Module in the signal path between Transceivers A and B. This equals 330 meters for Concentrator A and 230 meters for Concentrator B (560 meters total).

3.Subtract the equivalent fiber distance for each Fiber or Port-Switching Fiber Module in the signal path. This equals 50 meters for Concentrator A, 190 meters for Concentrator C, and 140 meters for Concentrator B (380 meters total).

4.Subtract all fiber cable lengths between the transceivers (450 m + 1000 m + 500 m + 75 m = 2025 meters).

Because the final remaining distance is greater than zero (1235 meters), the network configuration is legal.

Connecting External Network Devices

When connecting Thick or Thin Ethernet segments to an ONline network, you can use an:

❑ONline Ethernet Repeater Module

❑ONline Ethernet Bridge Module

❑External repeater or bridge

❑An IEEE Repeater or ONline Repeater Module each have an equivalent fiber distance of 800 meters

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