Howto synchronize 2 Online servers

Hello there, I'm looking for the best solution to synchronize 2 database servers: Machine A is on the intranet and people are feeding it data. Machine B is on the internet and people are looking at the data. For security reasons I would like to put machine B in a sort of read only mode. Also because of the fact that machine B is behind the firewall I only want as few holes as possible. I mean that an nfs mounting of a drive and doing an import and export is not a good solution . I was hoping to use some kind of replication mechanism using only the onlinetcp port. I've found something in the manual but the synchronisation is instantly. What i want is let's say at 14.00 a synchronisation takes places because then all the data entered at the intranet machine is verified. The servers are running Solaris 2.5.1 and Informix Online 7.21. The firewall is SUN Firewall One 3.0c Please reply also by mail because I'm reading a lot of newsgroups. Patrick Debois.