RAN box is child device of 128-port adapter. Each RAN box has 16-port and
there may have up to 8 RANs on one 128-port adapter for a total of 128 ports.

Don't confuse the RAN with the 16-port box type on the MCA 64-port adapter.
This type is rather known as CONCENTRATOR not RAN. This box also has 16-port
( 8 ports each side, not 16-port on the same side as the 128-port type.) Each
16-port CONCENTRATOR is attached directly on a dedicated port on one of the
4 port of the 64-port adapter for a total of 64 ports. This is a microchannel
adapter and there is no PCI or ISA version of the 64-port adapter.

There are 4 different FRU of RAN (128-port type ): standard EIA-232, enhanced
EIA-232, rack-mounted EIA-232 and EIA-422.

To get the correct information, it is recommended that you check the appropriate
128-port adapter page below. Some 128-port adapters don't support the enhanced RAN.

PCI 3-C #2944 128-Port Controller
ISA 3-9 #2932 128-Port Async Controller
MCA 3-7 #8128 128-Port Asynchronous
TYPE of RAN: FFC FRU FC Speed RAN 16-Port EIA-232 837 88G3842 #8130 1.2 Mbps ( Rack Mount) RAN 16-Port EIA-232 837 40H2589 #8136 1.2 Mbps Enhanced RAN 16-Port EIA-232 837 93H6549 #8137 2.4 Mbps Enhanced RAN 16-Port EIA-422 684 93H6563 #8138 2.4 Mbps Diagram:
Update: Jan 2003 by BJ Croft