3Com 5104M-FL1 Example a Network with 3 Concentrators, Example a Network with 6 Concentrators

Network Distance Calculation Examples

The following examples demonstrate how to calculate network distances for various all-10BASE-FL networks.

Example: A Network with 3 Concentrators

Refer to Figure 2-5, which shows a network with 3 concentrators.

To determine the maximum allowable link distance betweenConcentrators A and C:

1.Begin with 4200 meters (Ethernet Rule 3).

2.Subtract the fiber equivalent of the three concentrators with 10BASE-FL Modules that occur on the path between the two transceivers:

3 * 560 meters for each 10BASE-FL module = 1680 meters (Ethernet Rule 4)

3.Subtract the known amount of fiber cable between the two transceivers:

500 m + 500 m + 1 km = 2 km (Ethernet Rule 5)

4.The remainder is the maximum allowable distance of the link between concentrators A and C:

4200 m - 1680 m - 2000 m = 520 meters

5.Verify that the optical power budget is able to drive all of the link distances in the example. Because all link distances are only 1 km or less, and do not have any splices, this is not a problem.

Example: A Network with 6 Concentrators

Six concentrators are connected in Figure 2-6. Use this example to determine if the distances between transceivers are all within the 4200 meter maximum network diameter restriction for Ethernet networks.

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