You can set additional parameters for each machine to define:
Ways it can receive files from your machine
Directories for which it has read and write permission
Commands it can use for remote execution
A typical Permissions entry is:
MACHINE=datsun LOGNAME=Udatsun VALIDATE=datsun COMMANDS=rmail REQUEST=yes SENDFILES=yes
This entry allows files to be sent and received (to and from the "normal" UUCP directories, not from anywhere in the system) and causes the UUCP user name to be validated at login time.