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DRO significantly reduces the effects of packet loss by reordering the packets, so it only has to retransmit the lost packets and nothing else. DRO data throughput is often an order of magnitude greater than native throughput. Sometimes it's actually greater than the rated bandwidth (depending on the amount of bandwidth). These quantifiable throughput improvements can be traced directly to the cumulative effects of deduplication, compression, optimal window sizing, stacking, TCP termination and packet-loss mitigation.
Sometimes DRO throughput can be too efficient. It can completely seize the entire fat pipe, making it available only for those applications running through the DRO, which can block other apps from accessing the WAN. One way around this is to ensure the DRO product has rate-limiting capabilities or assigning only a fraction of the WAN bandwidth to the DRO (see "Data Replication Optimization [DRO] product comparison").
DRO is an excellent choice when bandwidth is high, packet loss exceeds .1%, distances are greater than 300 kilometers and when data migration applications have to move massive amounts of data across the WAN. DRO isn't normally a good choice when the bandwidth to ROBOs is relatively "skinny" (typically 1.5 Mb/sec or less), there's no quantifiable packet loss and the distances are very short. DRO also isn't a good choice if the amount of data moved over the WAN is light or insignificant, such as Web
This was first published in January 2007