3Com 5104M-FB1, 5102M-FBP, 510M-FBP Designing and Expanding the Network 2

To determine if the configuration meets Ethernet distance limitations for Transceivers A and B:

1.Use 4200 m as the maximum network diameter for a pure fiber network as defined by the 802.3 specification (Rule 3).

2.Subtract the fiber equivalent distance of 420 m for the signal entering the 10BASE-T Module from Transceiver B and 50 meters for the signal exiting the 10BASE-FB Module within the same concentrator (Rule 4).

3.Subtract the fiber equivalent distance of 190 m for the signal entering the 10BASE-FB Module in the top concentrator, and exiting a different port on the same 10BASE-FB Module.

4.Subtract the fiber equivalent distance (800 m) of the IEEE Repeater (Rule 4).

Note: In the reverse direction, a signal originating at Transceiver A loses 165 m of fiber equivalent distance when it exits the 10BASE-T Module to which Transceiver B is connected and

140meters for the signal entering the 10BASE-FB Module in the lower concentrator. Because the overall fiber equivalence of the path is greater for signals going from Transceiver B to A, the fiber equivalence of this path determines whether the link meets the 4200 m Ethernet link maximum.

5.Subtract the sum of intervening cable lengths:

150 m + 50 m + 200 m + 2000 m + 100 m = 2500 m

6.The remainder is 4200 m - 420 m - 50 m - 190 m - 800 m - 2500 m = 240 m.

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