In AIX 4.2, the rlogind daemon was changed to move portions of its code into the pseudo tty driver (ptydd) in the kernel. This change eliminated context switches needed to transfer a single character from an application to a terminal. This feature is enabled by default and cannot be configured.
In AIX 4.3, this change was extended to the telnetd daemon. Data coming in goes directly from the socket layer to the pty device driver's slave side. This change eliminated the need for a context switch of the telnetd daemon to write incoming data to the PTS (pseudo-terminal slave).
This option is turned on by default in AIX 4.3.2 and later releases. Before AIX 4.3.2, you must add a -a flag to the telnetd daemon in /etc/inetd.conf and refresh the inetd daemon.
Expected performance improvements for the rlogind and telnetd daemons with this feature is about 50 percent.