Asynchronous Serial Communications Programmer's Reference Manual (32022-90052)

134 Chapter7
Programming for PAD, DTC Telnet, Telnet/iX Server, and VT Devices
PAD Access to MPE/iX Systems
PAD support parameters for each MPE/iX host system that will allow
device connections via PAD must be defined in the NMMGR
configuration, along with the device profiles to be associated with PAD
devices. PAD devices requiring non-logon (programmatic) access must
be configured as nailed PAD devices. Devices that require only logon
access can be configured as non-nailed PAD terminals.
Security. Several levels of security are provided to assure that no
unauthorized access can be obtained to the MPE/iX systems on your
network.
See Using the OpenView DTC Manager for more information on
configuring and using security for incoming PAD calls.
For host-based security information, see Configuring and Managing
Host-Based X.25 Links.
PAD Device Access
All devices supported for asynchronous connection to the DTC can be
connected via PAD. The devices must support the PAD and modem port
configuration.
Hewlett-Packard provides a special terminal type file, terminal type 24,
for support of terminals connected via PAD. PAD support is provided for
serial printers with printer types 18 or 26.
Log On Access. If a terminal is properly configured for the PAD it is
connected to, and PAD connections are allowed for the MPE/iX network
you are accessing, you can establish a terminal session on a desired
MPE/iX system.
You must first establish a connection from the PAD to the system you
want to open the session on. You may choose to access a specific MPE/iX
system directly by entering that system’s X.25 address in the
connection request. Alternatively, you may access the DTC Switching
User Interface by entering the X.25 address of the DTC and connect to
the system you want by using the connection request provided by the
DTC Switching User Interface. (Regardless of how you choose to
initiate your connection, you will be able to switch between host
systems on the LAN once you terminate your session.)
NOTE When connected via PAD, you must log-off with the MPE :BYE
command to return to the PAD prompt. It is not possible to escape from
data transfer with a session active.
Your virtual connection is not disconnected until you log out from the
DTC switching user interface or until the inactivity timer configured
via the OpenView DTC Manager expires.
Only character mode and VPLUS block mode applications may be run
from PAD devices; no other types of block mode may be used.