Cabletron Systems BRIM-F6 manual Fddi Connection Rules

Page 34

APPENDIX A: BASIC FDDI NETWORKS

Connection Management (CMT) controls physical layer insertion and removal of stations. CMT has three main components:

Entity Coordination Management (ECM) controls bypass switches and coordinates trace (recovery) functions.

Configuration Management (CFM) controls PHY and MAC entity configuration within a node. Attaching or removing a station from the ring changes the logical structure of the ring.

Physical Connection Management (PCM) controls the physical connection between adjacent PHYs. It tests the quality of the link and enforces connection rules, screens marginal connections, and supports maintenance activities.

A.5 FDDI Connection Rules

One of the primary functions of SMT Connection Management is to control physical connections among A, B, M, and S type ports. The following table summarizes the FDDI connection rules.

 

A

B

S

M

 

 

 

 

 

A

V,U

V

V,U

V,P

 

 

 

 

 

B

V

V,U

V,U

V,P

 

 

 

 

 

S

V,U

V,U

V

V

 

 

 

 

 

M

V

V

V

X

 

 

 

 

 

V - valid connection

X - illegal connection

U - undesirable connection

P - valid, but when both A and B connect to M ports, only the B connection is active. Connecting A and B to M ports creates a dual homing configuration. Dual homing provides a redundant topology for concentrators. Figure A-6 illustrates how to configure three concentrators into dual homing configuration.

Page A-8

BRIM-F6 User’s Guide

Image 34
Contents BRIM-F6 USER’S Guide Page Contents Page Chapter Introduction Using This Manual Getting HelpBRIM-F6 Overview BRIM-F6 FeaturesBRIM-F6 Overview Related Documentation Chapter Installation Unpacking the Brim and the FPIMsInstalling the FPIMs Fpim ScrewsInstalling the BRIM-F6 Installing the BRIM-F6Installing a BRIM-F6 into a MIM Brim Tab Installing a BRIM-F6 into a Hub BRIM-F6 User’s Guide Chapter Using Lanview TWR Twisted Ring Chapter Specifications Fiber Optic InterfaceMultimode Receiver Signal Detect Single Mode Specifications Single Mode ReceiverUnshielded Twisted Pair Receiver Signal Detect Cable Specifications Shielded Twisted Pair Transmitter SpecificationsMultimode Fiber Twisted Pair Pinout Configuration Twisted Pair Cable LengthSafety EnvironmentAppendix a Basic Fddi Networks BRIM-F6 User’s Guide A-1Appendix a Basic Fddi Networks Reliability BRIM-F6 User’s Guide A-3Figure A-2. Wrapping a Broken Ring Ansi Standard X3T9.5 BRIM-F6 User’s Guide A-5Figure A-4. Token and Frame Formats BRIM-F6 User’s Guide A-7 Fddi StationFddi Connection Rules Fddi Devices BRIM-F6 User’s Guide A-9Figure A-7. Valid Station Configurations Figure A-8. Duplex Fiber Optic Receptacles and Connectors BRIM-F6 User’s Guide A-11A-12 BRIM-F6 User’s Guide A-13 Bypass State Operational StateFigure A-10. Fddi Devices Design Considerations For Fddi Networks BRIM-F6 User’s Guide A-15Bandwidth Figure A-11. Physical Device Connections BRIM-F6 User’s Guide A-17
Related manuals
Manual 74 pages 16.34 Kb