Sun Microsystems 1.0 - Manual (Page 89)

FDDI Network Architecture 63
6
Figure 6-11 Dua-Ring Network Divided by Two Faults
The maximum number of active optical bypass switches that can be connected
in a series is four. This assumes that the maximum distance between stations in
the ring is no more than 400m; otherwise, the aggregate attenuation in the ring
exceeds the total optical power budget.
Figure 6-12 shows how connecting an optical bypass switch to a dual-attached
station is used to conserve the connection when the station is switched off, or
removed from the ring.
Figure 6-12 Optical Bypass Switch
FDDI DAS
FDDI DAS
FDDI DAS
FDDI DAS
Failed FDDI DAS
Failed cable
Secondary ring
Primary ring
Optical bypass
B A
Dual-attached
station
Optical bypass
B A
Dual-attached
station
Pout Pin Pout Pin
Sout Sin Sout Sin
Active station Inactive station