What assumptions are made for off-site DR configurations?
For this model, the assumption is made that all data backed up at primary data center location needs to be duplicated to the DR site. Essentially a local copy is kept at the primary data center and a duplicate copy is made for the DR site. While this is a slight over simplification of the actual solution, it does provide a realistic comparison of the various alternatives. Adjustments for tape rotation/reuse, multiple copy needs or retention period management are not included in this model.
