Configuring and Managing MPE/iX Internet Services (MPE/iX 6.5)

52 Chapter3
Telnet Service
Implementation Differences
Implementation Differences
The implementation of Telnet on the HP 3000 does not use a separate
telnetd server file similar to the tftpd or bootpd server. Instead,
Telnet server functionality is provided by code that resides in
NL.PUB.SYS on version C.60.00 of MPE/iX. As a result, the last column
of the Telnet entry in the inetd configuration file is the word “internal.”
For example:
telnet stream tcp nowait MANAGER.SYS internal
By contrast, the entry for the BOOTP server in the inetd configuration
file shows “bootpd” in the last column because the BOOTP server is not
implemented internally. For example:
bootps dgram udp wait MANAGER.SYS /SYS/NET/BOOTPD bootpd
The implementation of the Telnet server as an internal program
concerns you as system manager, in the following two ways:
• When you issue a LISTFILE command for NET.SYS, you will not see a
telnetd server file. You do, however, edit the services file and the
inetd configuration file to enable Telnet on your system as you do
for the other Internet Services.
• Any security checking the host does before it initiates a Telnet
session for the requesting client must be handled by the Internet
daemon’s internal security. Specifically, this means that system
programmers cannot write “wrappers,” programs that wrap around
the Telnet entry in the configuration file to force a separate
security-checking program to run on that socket to determine if the
connection can or should be established. Instead, you use the inetd
security file to allow or deny specific nodes Telnet access to your
system. For information, read Chapter 2 , “Internet Daemon.”