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FDDI Management
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CAUTION
The following table summarizes the FDDI connection rules:
Table
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| A | B | S | M |
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| A | V, U | V | V, U | V, P |
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| B | V | V, U | V, U | V, P |
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| S | V, U | V, U | V | V |
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| M | V | V | V | X |
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V — | valid connection |
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X — | illegal connection |
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U — undesirable (but legal) connection; this requires that SMT is notified.
P— valid, but when both A and B are connected to M ports (a
Though technically legal under FDDI connection rules, undesirable connections will cause a twisted or wrapped ring.
Each SMT entity maintains its own connection policy; however, when two interfaces attempt to connect, their combined established connection policies dictate the connections that will be allowed. In an attempted connection between two nodes, the most lenient policy will determine whether the connection (as long as it is legal) can be made. For example, if two FDDI nodes attempt an AÑ>A connection, and this connection is not allowed at one FDDI node but allowed at the other, the connection would be accepted. If the connection policy at both nodes disallows the connection, the connection will be rejected.
This is a
Connection Policy |