managing user accounts without NIS

[Borries Demeler]

> In a nutshell:
> 
>   ssh adds .17 seconds compared to (roughly .1 second baseline) rsh per
> call
>   scp adds the same .17 seconds per call PLUS roughly .36 seconds per
> megabyte, using default idea encryption.

Just wondering:

Normally, I would expect that most beowulfs are configured to be behind a
tightly closed firewall with the exception of ssh access. Having secured
the beowulf in such a way, and assuming I have physical security (i.e.,
inaccessible consoles), can an argument be made that one shouldn't use
rsh? Even if the system is only used by one user?
If so, I would be interested in the arguments against using rsh. 

Thanks, -Borries