Thank you for your reply, Bob. I used the Catalyst technical white paper as a reference to set up this configuration.
http://h20195.www2.hp.com/v2/GetPDF.aspx%2F4AA4-8380ENW.pdf
Page 10 states the following:
"One of the key features HP StoreOnce Catalyst stores provide is allowing HP Data Protector to utilize low bandwidth copy feature to replicate backup data. (...) This is accomplished by using HP Data Protector’s Object Copy feature. Replicating backup data between HP StoreOnce Backup systems is accomplished by properly configuring HP Data Protector Object Copy to replicate the backup data to alternate deduplication devices, one being the original back up data store and the other being the copy data store."
And on page 4:
"HP StoreOnce Backup systems common deduplication engine allows replication to remote sites with limited bandwidth and without having to be rehydrated."
Also found some information in the product webpage:
"HP uses a single federated deduplication engine, from application source to backup servers and target appliances, so you can quickly and efficiently move data from point to point."
Since Catalyst uses a single federated deduplication engine, it implies each catalyst store is aware of other stores when executing a copy job, be it from data protector or any other application that is capable of integrating with the StoreOnce backup system, and so all replication should be automatically federated. One evidence of this is that there is absolutely no "federated replication" option in either the StoreOnce management console or Data Protector. Even though the expression "federated" isn't explicitly used in page 10 of the aforementioned documentation, I believe "low bandwidth copy" is very likely to be the same thing. Other HP documents also refer to federated replication as being "low bandwidth".
Besides, if Object Copy is a restore followed by a backup, how come I don't need to specify a platform to perform a restore in case of integrated backups (databases, VMware, etc)?? Are you sure it works like that internally?