Central Backup Server

I see in the howto it mentions a central backup server having the 
backups done on each host and pushed up to the server.    I would like 
to set up my system to have a central backup server on my most trusted 
network and have it pull backups from the other servers on the same and 
less trusted networks.    Since the ssh connections can only be 
initialized from the trusted network to the less trusted network and not 
the other way round, the backups must be pulled by the central server 
rather than pushed from the clients.   I would also like the central 
server to have the ssh key/keys to the clients rather than each client 
having a key to the server.   Is this configuration possible?

Thanks
Rich
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Richard Hall
Systems Administrator
Information Security Group
Royal Holloway, University of London
Tel: +44 (0)1784 44 3111
Fax: +44 (0)1784 430766
gpg Key fingerprint:
D3AC 1999 9ECC F458 DFCC  FF00 1ACA 8812 F055 BF2F
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