IBM 5500 Operational, Installation, And Maintenance Manual page 35

To take advantage of the 2Mbps Mode, IBM recommends that you install
your Express devices on a different port than your legacy devices. Also,
ensure that you have Express-enabled Hubs and Multiplexers (IBM 7299).
Figure 8 is an example of an IBM 5500 remotely connected to an AS/400
through asynchronous or ISDN modem.
Asynchronous Modems
or ISDN
5500 Express IP
Control Unit
AS/400
Twinax
Breakout Box
Twinax
Twinax Express TCP/IP Twinax Express TCP/IP
Twinax Network Station
55E1I003
Figure 8: IBM 5500 Express WAN Connectivity
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