1-1

Chapter 1

Introduction to SPMA for the SEHI100TX-22
How to use the SEHI User’s Guide; manual conventions; contacting Cabletron Global Call Center;
SEHI firmware versions supported by SPMA
The SEHI100TX-22 is an intelligent repeating Fast Ethernet hub, which when
combined with the SEH100TX-22 non-intelligent stackable hub, can provide from
22 to as many as 120 100Base-TX Ethernet connections in a single stack. Each
SEHI100TX-22 and SEH100 TX-22 provides front panel ports for network
connections, and a rear-panel HUBStack Interconnect Bus port for stackable
connections.
The SEHI100TX-22 intelligent stackable hub is designed to manage one or more of
the SEH100TX-22 non-intelligent stackables. It provides 22 100Base-TX network
ports via RJ45 connectors and one optional user-conÞgurable EPIM port (which
allows for ßexible network connection options, including SMA or ST Þber optic
cable, thin coax, or AUI cable). Although the SEHI100TX-22 is the management
device, providing full packet and error statistics for the stack, it can be located
anywhere in the stack.
Each SEH100TX-22 non-intelligent hub provides 22 100Base-TX network ports
via RJ45 connectors and two optional user-conÞgurable EPIM ports. Up to four
SEH100TX-22s can be included in the stack. The entire stack is counted as only
one repeater hop.
The SEHI100TX-22 fully conforms to the IEEE 802.3 Repeater, AUI, and 10BASE-T
speciÞcations. It will transmit re-timed data packets, regenerate preamble, extend
fragments, arbitrate collisions, and automatically partition problem segments.