Cabletron Systems SEHI-32 Manual Do Utilizador

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INTRODUCTION
 
Page 1-3
The SEHI-22/24 and SEHI-32/34 are functionally identical with the 
exception of the network ports:
 
SEHI-22
 
, 12 RJ45 network ports and one EPIM port.
 
SEHI-24
 
, 24 RJ45 network ports and two EPIM ports.
 
SEHI-32
 
, one 50 pin Champ connector, providing 12 twisted 
pair segments, and one EPIM port.
 
SEHI-34
 
, two 50 pin Champ connectors, providing 24 twisted 
pair segments, and two EPIM ports.
 
1.4
SEHI FEATURES
Repeater Functionality
 
The SEHI fully conforms to the IEEE 802.3 Repeater, AUI, and 
10BASE-T specifications, and provides the flexibility to connect 
networks using IEEE 802.3, Ethernet Version 1 or Version 2 
equipment. The SEHI transmits re-timed data packets, regenerates 
the preamble, extends fragments, and arbitrates collisions.
The SEHI automatically partitions problem segments, and reconnects 
repaired segments to the network. This feature minimizes the impact 
on network operation resulting from a problem on one segment by 
isolating the problem segment. Only devices on the problem segment 
are affected. When the problem is solved, the SEHI automatically 
reconnects the isolated segment to the network.
 
Polarity Detection and Correction
 
Each twisted pair port on the SEHI incorporates a Polarity Detection 
and Correction feature that allows the SEHI to pass data regardless of 
the polarity of the twisted pair segment’s receive link. We do not 
recommend operating in this condition. If you discover this condition, 
remove the segment from the network and wire it correctly. This 
reduces the potential for problems if equipment changes are made. 
 
Flash EEPROMs
 
The SEHI uses Flash EEPROMs that allow you to download new and 
updated firmware using Cabletron’s Remote LANVIEW/Windows, 
version 2.3 or later or any device using BOOTP or TFTP protocols.