Filter
Top Products
Magnum 8000X Mixed-Media Fiber Hubs Installation and User Guide (05/ 02)
15
www GarrettCom com
..
2.6 10 /100 Speed Auto-sensing (8000X front copper ports only)
Twisted pair copper ports (PM-RJ45 or PM-RJ45U only) support auto-
sensing for speed, independent of the other ports. Speed-sensing is performed by the
Magnum 8000X’s electronics in accordance with the standards of the IEEE 802.3u
auto-negotiation standard. If the connected device or node indicates that it is capable of
100Mbps speed, then operation on that port will be at 100Mbps. If the connected
device does not positively indicate that it is capable of 100Mbps speed, then the
operation on that 8000X port will be at 10Mbps. Of course, the hubs’ auto-negotiation
technique is only for 10 / 100 speed, and does not provide for any full-duplex operation.
When a twisted-pair port is connected and LINK is present, the speed on that
port that has been sensed by the Magnum 8000X Mixed-Media Fiber Hub will be
indicated by the ‘S’ LED for that port. The ‘S’ LED is steady ON when 100Mbps speed
is sensed, and is steady OFF when 10Mbps speed is in use. When the port is not
connected, the ‘S’ LED on that port will be blinking to indicate that it is trying to auto-
negotiate. (See section 4.3 for the LED’s).
2.7 Stacking Magnum Mixed-Media 8000X Fiber Hubs
The rear of the Magnum 8000X Mixed-Media Fiber Hubs have an Inter-
Repeater Bus (IRB) connector on the left side. The IRB interconnects stacked units with
a stacking cable, enabling all stacked Magnum 8000X units to operate as a single dual-
speed repeater. There are two 25-pin IRB connectors on each unit: the bottom IRB
connector which is used to daisy chain the IRB to the stacked unit below (unused on
bottom unit in a Magnum 8000X stack); and the top IRB connector which is used to
daisy chain the IRB to the stacked unit above (unused on top unit in a Magnum 8000X
stack). The IRB connectors for non-stacked units are unused.
The IRB stacking shielded cables supplied with each Magnum 8000X-A unit
are slightly longer than the base unit height. The operation of the stack will not be
impaired by longer IRB RS232 cables. Stacks with total IRB lengths of as much as 9-
inch long shielded cables can be implemented. However, non-standard IRB cable
lengths, longer cables or unshielded cables are not permitted as they will not operate
properly at 100Mbps speeds.
The 8000X Mixed-Media Fiber Hub can be stacked with Magnum DS8016-A
models, too. (But not with DS8016-B because of the “bridge-inside” conflict)