Why are Patch Management and Change Management Important?
Alvaka Networks has arguably the best and most sophisticated patch management process in the Orange County, Los Angeles County and possibly the US. Not many firms can deploy vast quantities of patches to valuable high availability servers and PCs with smoke testing qualify control while following the sun globally during selected narrow service windows.
Change Management
Change management is vital to every stage of the patch management process. As with all system modifications, patches and updates must be performed and tracked through the change management system. It is highly unlikely that an enterprise-scale patch management program can be successful without proper integration with the change management system and organization.
Like any environmental changes, patch application plans submitted through change management must have associated contingency and backout plans. What are the recovery plans if something goes wrong during or as a result of the application of a patch or update? Also, information on risk mitigation should be included in the change management solution. For example, how are desktop patches going to be phased and scheduled to prevent mass outages and support desk overload? Monitoring and acceptance plans should also be included in the change management process. How will updates be certified as successful? There should be specific milestones and acceptance criteria to guide the verification of the patches' success and to allow for the closure of the update in the change management system....
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.