Cabletron Systems SPECTRUM, Руководство пользователя

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FDDI Management
4-22 Configuring the SMT Connection Policy
Figure 4-10. SMT Connection Policy Window
FDDI Connection Rules
By default, all connections are allowed except the illegal M—>M connection; the
following table summarizes the FDDI connection rules:
V — valid connection
X — illegal connection
U — undesirable (but legal) connection
T — connection can lead to a twisted ring configuration
DH — when both A and B are connected to M ports, a dual-homing configuration
results. See the following page for more information on dual homing.
Table 4-1. FDDI Connection Rules
A B S M
A
V, U (T) V V, U V, DH
B
V V, U (T) V, U V, DH
S
V, U V, U V V
M
V, DH V, DH V X
!
CAUTION
Though technically legal under FDDI connection rules, the undesirable A—>S and
B—>S connections will deprive your device of the redundancy protection built in to the
FDDI dual-ring configuration. The SMT entity is notified each time an undesirable
connection is made, even when that connection is allowed.