7.  Lessons

      The following is a summary of the lessons we learned in building these programs.

1.

By starting your network in a way that requires no hardware or major operating system changes, you can get going quickly.

2.

Support will follow use. Since the network existed and was being used, system maintainers were easily persuaded to help keep it operating, including purchasing additional hardware to speed traffic.

3.

Make the network commands look like local commands. Our users have a resistance to learning anything new: all the inter-system commands look very similar to standard UNIXsystem commands so that little training cost is involved.

4.

An initial error was not coordinating enough with existing communications projects: thus, the first version of this network was restricted to dial-up, since it did not support the various hardware links between systems. This has been fixed in the current system.

Acknowledgements

      We thank G. L. Chesson for his design and implementation of the packet driver and protocol, and A. S. Cohen, J. Lions, and P. F. Long for their suggestions and assistance. $LIST$