Tcpd

tcpd is a computer program based on Unix operating systems that encapsulates the requests of the TCP-based services that the inetd service manages.

Verify that the source where the connection request occurs is reliable and logs that request into the syslog daemon. The files in charge of managing access control are /etc/host.allow and /etc/host.deny. Once tcpd has checked that everything is fine, it starts the corresponding server and finishes its own execution.

Here is an example of the contents of the /etc/inetd.conf file: ftp stream tcp nowait root /usr/sbin/tcpd in.ftpd telnet stream tcp nowait root /usr/sbin/tcpd in.telnetd

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