The default ports used by Kerberos are port 88 for the
port 749 for the admin server. You can, however,
choose to run on other ports, as long as they are specified in each
krb5.conf files, and the
kdc.conf file on each KDC. For a more thorough treatment of
port numbers used by the Kerberos V5 programs, refer to the
“Configuring Your Firewall to Work With Kerberos V5” section of
the Kerberos V5 System Administrator's Guide.
 Kerberos V4 used port 750. If necessary, you can run on both ports for backward compatibility.