server secret

Hi all.

I'm a little confused about something.

In the default current.conf file that came with the RPM distribution of
1.4.0, there is a lot of documentation up in the top of the file, most
of which is absolutely perfect, except for this one thing that now has
me baffled:

~~~~~~~~ SNIP ~~~~~~~~~~~~~
# server_secret = text to get sha1'd for systemid tokens.
#                 Must be kept secret, and site specific.
~~~~~~~~~~ SNIP ~~~~~~~~~~~~~

What?  What does "sha1'd" mean?  Why do I need to 'get' this, and the
systemid tokens (client or server?)?  What's at risk by not keeping this
a secret?  When will I or any of my clients ever need or see this secret
again?  What's going on? 

In all of my client testing thus far, I've never used the system secret
for anything but to put it in the current.conf file.  

Thanks for any input here.
brian.
-- 

Brian K. Jones
System Administrator
Dept. of Computer Science, Princeton University
http://www.linuxlaboratory.org
[email protected]
Voice: (609) 258-6080