TCP/IP help?

[e@Flavors.COM (Doug Currie, Flavors Technology, Inc.)]

A customer has insisted that we use TCP/IP for communication between Macs
running MCL. Heretofore we have been using Appletalk and PPC. I have two
questions, one MCL related, one TCP/IP specific:

1) Besides the ccl:library;MacTCP.Lisp and ccl:examples;webster.lisp and
the files on the CD-ROM in TCP Examples... does anyone know of any publicly
available MCL TCP/IP source code for (generic) Program to Program
Communication?

2) How does one go about choosing a "TCP port number" -- it appears that
several numbers have been established as standard, e.g., ("finger" . 79),
but how do I choose numbers to be used in a semi-public network that will
not conflict with other users' choices? [Please reply directly to me on
this question since it is probably not of interest to the info-mcl list.]

Thanks,
e