
The tsunami that affected Japan in 2011, a type of natural disaster (Wikipedia)
Both terms often get mixed up with each other in the world of data backup. But in fact, Business continuity planning is seen as the broader concept and consequently includes Disaster Recovery planning.
Eventually, both two terms bear the same message: Always be alert and prepared for the sudden event of a system malfunction or something bigger.
IT disasters can range from minor to major: From the loss of just some data to the loss of an entire dataset or an overall system failure. All can be caused by a severe software problem, a technical malfunction or by external events. Examples for external events are the devastating flood caused by Hurricane Katrina in the U.S. in 2005 or the 9/11attack in New York, which changed the way people look at data centers today, or the tsunami in Japan in 2013.
But more often the causes are internal (e.g. human errors!) and do not necessarily have an impact on the whole system. Still, they can lead to smaller hick-ups or longer outages, both unpleasant for businesses depending on constant availability.
Disaster recovery now primarily aims at saving the data and recovering it in the event of a disaster. Originally data was kept in a secondary site, with plans set up on how to keep this data up-to-date and how to make it available in the case of a disaster.
Business Continuity (BC) on the other side is not data centric. It aims at keeping up the whole business chain. Ideally, Business Continuity ensures that IT continues to function in spite of a disaster – without any downtime or data loss! This can be done by keeping the data at several different places at the same time connected with short switch-over times. So, if one system fails, the other one can take over seamlessly.
So, Business Continuity is the broader term and with a proper BC plan in place, end-users might not even recognize the outage of one system.
Credits / Sources:
Wikipedia: Business Continuity Planning
Wikipedia: Disaster Recovery
Cio: Difference between DR and BC
9/11: Are Lessons Learned Still Being Applied?
Image Wikipedia: http://en.wikipedia.org/wiki/Disaster_recovery_plan


