Disaster recovery using remote location backup Remote Copy Disk Buffered REC over Low bandwidth Networks

To provide remote copying over low-bandwidth networks, a Consistency mode is provided. This uses part of cache memory as a buffer (The REC buffer). Data is then copied to the destination device and compiled on a block basis after accumulating the I/O from multiple REC sessions in the REC buffer for a specific period. Use of this mode provide the control to maintain transmission integrity even when data is transmitted out of order, due to transmission delays, as it travels to the destination device over the WAN.
In addition, if cache memory capacity becomes insufficient, due to instabilities in the link or increased traffic, disk buffered REC can be used. This supports temporary increases in updated data using the larger buffering capacity of hard disks.

Benefits

• Able to configure disaster recovery systems using low cost, low bandwidth networks.
• Large capacity buffer supports temporary increases in data updates.
• Even when data updates exceed the bandwidth, data transmission continuity is
  guaranteed by maintaining update order.