In brief as defined on Wikipedia the definition is “The recovery time objective (RTO) is the duration of time and a service level within which a business process must be restored after a disaster (or disruption) in order to avoid unacceptable consequences associated with a break in business continuity.
It can include the time for trying to fix the problem without a recovery, the recovery itself, testing, and the communication to the users. Decision time for user’s representative is not included.”
Put another way, if your system breaks, how long do you want to be down? How soon do you need your system back up and running? Whether it is a week, a day, an hour or one minute, whatever time you establish, that is your RTO or Recovery Time Objective. Think about what your business needs and talk to other key business unit managers and you can come up with one component of disaster recovery/business continuity planning. Next up, you need to start thinking about your Recovery Point Objective.
Image courtesy of 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.