Magnum DS8016 Dual-Speed Stackable Hubs Installation and User Guide (07/06)
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industry standards normally permit, and is different from what competitive 100Mbps Class II
hub products normally allow. This additional cascading level and cable length is due to the
relatively shorter bit time (80 BT actually measured, for front-port-to-port) delay of the
Magnum DS8016 vs. the industry standard delay of 92 BT for Class II repeaters. The
installation flexibility and network growth potential is accordingly better with Magnum
DS8016 s than with hubs that merely meet the standard.
Table 3.2.3c shows maximum cable lengths for common network configurations
using industry standard repeater PDV numbers. Calculations such as above should be
performed using measured PDV data supplied by the equipment manufacturer in important
installations.
Table 3.2.3c: Maximum segment lengths for common network configurations
Number
of Hubs
Repeater
Hop Count
Max. User
Segment
Lengths (m)
Max. Inter-
Repeater (Cascade)
Length (m)
Notes
1
1
100.0
n.a.
All ports TX
2
2
100.0
5.0
All ports TX
2
2
92.0
20.0
All ports TX
3+
3
60.0
1.0
All ports TX
Instructions for connecting the Magnum DS8016 Dual-Speed Hubs to the various
Fast Ethernet media are given in the following sections.
3.2.4
Connections to NICs which support Auto-Negotiation
The Magnum DS8016 Dual-Speed Hub will function properly with NICs (Network
Interface Cards) which support Auto-Negotiation. The Magnum DS8016 will establish link
with any NIC which can send and receive the Fast Link Pulse (FLP) coding for the
100BASE-TX signaling system. When connecting a NIC to the DS8016, it may be
necessary to reload the NIC drivers on the user device if the NIC has been communicating
with a protocol other than 100BASE-TX (such as 10BASE-T). When 100Mb operation is
agreed and in use, the 100Mb LINK/ACT LED is illuminated, steady ON if no traffic or
blinking when there is traffic.
3.3
Powering the Magnum DS8016
Magnum DS8016 Dual-Speed Hubs incorporate an internal universal power supply,
and have a recessed male IEC connector for the AC power cord in the rear. A six-foot 115