<<My company uses FB 1.56 (mostly embedded) and am needing a solution
for synchronizing DBs. I'm a little confused as I hear that
replication is one way and synchronization is two way, yet IBReplicator
(by IBPhoenix) does synchronization (but its name would
suggest otherwise).>>

IBReplicator supports uni and bi-directional replication, as well as
synchronisation.
Typically synchronisation is used to bring two disparate databases of
the same structure
up to date (containing the same data) before initiating replication.

Paul