There is nothing linear about the process. There are three distinct platforms in this development that are constantly interacting. They ultimately determine whether an individual meets those standards. Acting individually, each vendor constructs a set of examinations that signals a comprehensive competence. A certificate is to be awarded to individuals who pass the required examinations.
Some certificates require performance assessments and industry experience in addition to the tests.
The certificate is given a discrete vendor-based name, e.g. Microsoft Certified Systems Engineer. Within fields covered by a certificate, vendors establish sub-specialty certificates, and some create hierarchies of certifications analogous to hierarchies of academic degrees. Vendors recognize that their product-systems share a great deal, and, in practical circumstances, interact. Networks are a good example of a territory in which this commonality and interaction can be observed. Some standards for performance, then, become generic.