Cabletron Systems MicroMMAC-24E Installation Manual

Contents

Cabletron Systems MicroMMAC-24E Installation Manual Manual pdf 13 page image

Chapter 1: IntroductionPage 1-4MicroMMAC Installation Guide1.5 MicroMMAC FEATURESRepeater FunctionalityThe MicroMMAC fully conforms to the IEEE 802.3 Repeater, AUI, and10BASE-T specifications, and provides the flexibility to connectnetworks using IEEE 802.3, Ethernet Version 1 or Version 2 equipment.The MicroMMAC transmits retimed data packets, regenerates thepreamble, extends fragments, and arbitrates collisions.The MicroMMAC automatically partitions problem segments, andreconnects repaired segments to the network. This feature minimizes theimpact on network operation resulting from a problem on one segment byisolating the problem segment. Only devices on the problem segment areaffected. When the problem is solved, the MicroMMAC automaticallyreconnects the isolated segment to the network.Polarity Detection and CorrectionEach twisted pair port on the MicroMMAC incorporates a PolarityDetection and Correction feature. This feature allows the MicroMMAC topass data regardless of the polarity of the twisted pair segment’s receivelink. Cabletron Systems does not recommend operating in this condition.If you discover this condition, remove the segment from the network andwire it correctly. This reduces the potential for problems in the future ifequipment changes are made.Local ManagementLocal Management allows you to manage the MicroMMAC and all itsattached segments. It also provides full packet and error statistics for theentire stack, individual device, or individual port. You access LocalManagement by attaching a DEC VT320 terminal or a PC using VT320emulation software to the MicroMMAC’s RJ45 COM 2 port. Refer to theMicroMMAC Local Management User’s Guide for instructions on how touse Local Management.LANVIEW LEDCabletron Systems LANVIEW status monitoring and diagnostics systemis a troubleshooting tool that helps diagnose power failures, collisions,cable faults, and link problems. LANVIEW LEDs are convenientlylocated on the MicroMMAC front panel.