Pushing files onto ftp-master

[Stephen Montgomery-Smith]

I am the person in charge of maintaining CTM (CVSUP via email). 
Currently I create the CTM files on my home machine.  A few times a day, 
ftp-master uses rsync to extract the CTM files from my machine, and from 
there it goes out to the internet.

I am now being told that I may need to get behind a firewall in the next 
few months.

Is there a mechanism where I could rsync, as the client, onto 
ftp-master?  That is, instead of ftp-master initiating the rsync 
connection, that I initiate the rsync connection?

Thanks, Stephen