The service runs from a public account on uk.ac.nsf.sun (X29 address 000040010180). Make a call to this machine, and login as guestftp, using the password guestftp.
You should then be presented with a screen of operational information, followed by update times of the `help' and `netnews' files. Please check these files if they have changed since the last time you used the service.
The service will then ask you to supply a reference - this will be the name of the temporary directory where your files will be stored. Remember the reference - you will need it when transferring files to your home machine from uk.ac.nsf.sun.