Cabletron Systems STHI - Manual (Page 11)

STHI Overview
Page 1-2
Figure 1-1. Front and Back Views of the STHI-24
The STHI may be installed as a fully managed stand-alone device, or it
may be stacked with up to four STH hubs, each of which adds 12 or 24
TCU ports to the LAN, bringing the total count to a maximum of 120
managed TCU ports in the stack. The STHI serves as the logical “top” of
the stack and provides full frame and error statistics for the managed ring.
The STHI fully conforms to IEEE 802.5 Token Ring specifications for
connectivity to Token Ring equipment and offers the following Token
Ring enhancement features:
• Local Management, a user interface for management control;
• Cabletron Systems’ Automatic Beacon Recovery Process (ABRP);
• Multiple Ring Out connectivity for Passive MAU workgroups;
• automatic speed fault protection;
• active filtering, equalizing, and amplify ing circuitry;
• and LANVIEW LEDs for “at-a-glance” diagnostic monitoring.
1.2.1 LANVIEW LEDs
Cabletron Systems’ LANVIEW status monitoring and diagnostics system
is an array of LEDs which helps users to diagnose power failures,
beaconing conditions, cable faults, and connection problems. Refer to
Section 4.1,
LANVIEW LED Signals , for more detail.
LANVIEW ®
SUPPORTING 100 OHM UTP CABLE
HubSTACK
STHI-24
TOKEN RING HUB WITH
24X 23X 22X 21X 20X 19X 18X 17X 16X 15X 14X 13X
12X 11X 10X 9X 8X 7X 6X 5X 4X 3X 2X 1X
RI RESET
CPU ACT
MGMT 16 Mb/s
SPEED
16M 4M
COM RO
STACK 3 STACK 2 STACK 5 STACK 4
STHI-24 TOKEN RING HUB LANVIEW® WITH