21
16-PORT TYPE 3 MAU
The length of the main ring is critical to the proper operation of the token-
ring network. If the network is designed without taking the length of the
backup path into consideration, the backup path may not be usable if it is
needed. It may force the signal to be transmitted so far that attenuation
makes it unreadable.
When the network is first activated at the start of a business day, it may
consist of only one active attaching device connected to the main ring. For
this example, assume that the attaching device is on the longest lobe.
MAU
100 feet
50 feet
150 feet
50 feet
x 2
Longest
Lobe
Attaching
Device
Actual transmission path distance:
(50 x 2) + 150 + 50 + 100 = 400 feet
MAU
MAU
Figure 3-3. Main ring and first device. The backup path is not in use.