In brief as defined on Wikipedia the definition is “A recovery point objective, or “RPO”, is defined by business continuity planning. It is the maximum tolerable period in which data might be lost from an IT service due to a major incident. The RPO gives systems designers a limit to work to. For instance, if the RPO is set to four hours, then in practice, off-site mirrored backups must be continuously maintained – a daily off-site backup on tape will not suffice.
Put another way, if your system breaks, how much information are you willing to lose when your system is recovered? If you only back up once per day after work concludes at 5 PM, assuming you are working an eight hour day your RPO is essentially eight hours. If at the end of the day you finish work and your system crashes and all data is lost, you have then lost the full eight hours of work. If data is lost half way through the day, your effective Recovery Point at that point is four hours, but don’t confuse that with your objective which is set at eight hours. In this scenario, RPO done properly you should not lose more than eight hours’ worth of work.
RPO can and should be calculated differently for different systems you use. Your Exchange Mail Server and SQL Servers should probably have an RPO of 15 minutes to one hour. DNS servers and a static website can do fine with a 24 hour RPO since they rarely change.
You should also consider what you want for your localized RPO vs. your off-site storage RPO. Locally you might want to have your RPO on critical servers set to one hour, but for bandwidth practicality and cost your off-site RPO may be fine at 24 hours.
If you like this information consider reading my previous blog on RTO – Recovery Time Objective.
Think about what your business needs and talk to other key business unit managers and you can come up with this part of your disaster recovery/business continuity planning.
Image credit Cisco Systems
Alvaka Networks, an Irvine based IT consulting and IT Managed Service company, can help you with you DR and Business continuity planning. We work all over Orange, Los Angeles and Riverside counties. Call (949) 430-7285 or write for a free RTO, RPO Disaster Recovery and Business Continuity consultation. Our DRworx disaster recovery service backs-up your valuable data onsite and in the cloud. It also provides for a fast RTO/RPO through virtualization so if your server fails you can be back up and running fast. Off-site storage in the cloud protects you from localized disaster. Reverse chaining technology assures you that your system will always recover quickly from a failure. We offer many other IT Services and IT Outsourcing options to help you with your computer service needs.
Smoke testing is a term used to describe the testing process for servers after patches are applied. 
Estimating an average time for patching servers and PCs can be a bit tricky. It can vary from one month to the next, depending upon the number and complexity of the patches released by your software vendors. You must consider all versions of operating systems and have a complete inventory of all your application software to do this job correctly. Our experience has shown that manual patching of systems takes on average of about 1.5 hours each.
This is a basic cost calculator for you to compute your typical monthly cost for patching your servers, PCs, laptops, tablets and associated application software. It also forms the basis for you to begin calculating your Return on Investment for software patching, or for comparison with alternatives to the manual process of patching operating systems and application software—such as Patch Management as a Service, also known as Vulnerability Management as a Service.