A technique to name data is disclosed to allow preservation of storage efficiency over a link between a source and a destination in a replication relationship as well as in storage at the destination. The technique allows the source to send named data to the destination once and refer to it by name multiple times in the future, without having to resend the data. The technique also allows the transmission of data extents to be decoupled from the logical containers that refer to the data extents. Additionally, the technique allows a replication system to accommodate different extent sizes between replication source and destination while preserving storage efficiency.