Configuring Systems for Terminals, Printers, and Other Serial Devices (32022-90051)

Chapter 1 25
Introduction
Typical Network Configurations
PAD Access
DTCs can optionally contain up to three DTC/X.25 Network Access
cards. DTC/ X.25 Network Access cards connect devices to computers
over a Packet Switching Network (PSN), by using a private or public
PAD.
A PAD,orPacket Assembler/Disassembler, is a device that converts
asynchronous character streams into packets that can be transmitted
over a PSN. Supported devices attached to the DTC can be remotely
connected using a PAD.
Figure 1-2 shows PAD access to HP 3000 and other computers using a
DTC equipped with the DTC/X.25 Network Access card. Note that only
terminals are connected to the public PAD. This is because devices that
are opened using the software, such as serial printers, must be
connected to a private PAD and must be permanently associated with a
reserved logical device (ldev) number on the MPE/iX that accesses
them.
Figure 1-2 DTC/X.25 Network Access for a PAD