3com 100 TX User Manual

Page of 64
3-4
C
HAPTER
 3: M
AKING
 FMS 100-TX H
UB
 C
ONNECTIONS
Hub-to-Hub
Interconnection
You can interconnect up to eight hubs, using expansion cables to form one 
logical unit. (The hub expansion cable is also designated the inter-hub bus 
[IHB] cable.) Interconnecting eight hubs will provide a maximum of 104 ports 
(96 RJ-45 ports from the front panels and 8 ports from the transceiver 
interface modules inserted in the hubs’ rear panels).
You do not have to turn off the power if you are connecting hubs using 
expansion cables. 
Use the hub expansion cable (3C219) to connect the UP expansion port on 
the rear panel of one hub to the DOWN expansion port on the next hub, as 
shown in Figure 3-4. (The hub expansion cable must be purchased 
separately.) Repeat this step for each hub in the stack.
Figure 3-4   Interconnecting Two Hubs
UP
DOWN
EXPANSION
E
D
UP
DOWN
EXPANSION
E
D
DOWN 
expansion 
port
UP expansion port