Port Connection Rules; Definitions For The Port Connection Rules - 3Com 3C780 - LinkBuilder FDDI Base Unit User Manual

3-14 Configuring the Hub
Table 3-3. Port Connection Rules
Attachment
Ports
A
B
M
S
Table 3-4. Definitions for the Port Connection Rules
Condition
Indicator
P
U
V
X
(continued)
Neighbor
Ports
A B
V, U, T V
V V, U, T
V, W V, W
V, U, W V, U, W
Port Connection
Condition
Prevents thru state
Undesirable connection
Valid connection
Illegal connection
M S
V, P, W V, U, W
V, P, W V, U, W
X V
V V
Definition of Port
Condition
Exists when both rings are
not fully functional. Thru
state is the normal condition
of an FDDI station.
Exists because the connection
creates undesirable hub
configurations, such as a
twisted ring; not prevented by
the connection rules.
Creates two logical token
rings; provides a consistent
designation of the primary
ring among all stations.
Exists when an M-to-M
connection is formed. It
isolates a portion of the
network onto a separate
token ring nested in the tree
of rings.