You can configure System/370 channels to use either DC Interlock (double-tag) mode, or Data-Streaming mode.
You can configure data-streaming mode for one of the following transfer rates:
Use the highest data-streaming mode rate supported on the attaching host system.
When connecting directly to a System/370 channel, you can locate the printer at a maximum distance of 122 meters (400) feet from the channel if it is the only control unit on the interface. For each additional control unit ahead of the printer on the channel, the maximum distance is reduced by 4.57 meters (15 feet).
You also can connect the printer to the remote end of either an IBM 3044-II Fiber Optic Channel Extender or an IBM 9034 ESCON Converter to extend the maximum channel length by up to 3 kilometers (1.875 miles).
The IBM 9034, with either an IBM 9032 or 9033 ESCON Director, further extends the maximum channel length by up to 6 kilometers (3.750 miles) with one 9032/9033 in static connection mode (with RPQ approval), or by up to 9 kilometers (5.625 miles) with two 9032/9033 in static connection mode (with RPQ approval).
The Extended Distance Feature (XDF) on the 9032/9033 ESCON Directors also extends the distance. Submit an RPQ if you require the XDF. The RPQ approval specifies the maximum distance allowed for your environment.
The following figure shows the details of the above connection options, with the distance extensions shown on the Host System side of the diagram.