There are two broad operating models prevailing for crowdsourced testing include:
Testing as a service: Here, the QA vendor identifies internal employees as a private crowd along with a crowdtesting platform and testing tools to enable the client to manage end-to-end testing using their own crowdtesting champions. This is the most common format of managed crowdtesting services, and the client pays only for the outcome of the testing, for example, the number of critical bugs identified in a given time frame and the severity of the bugs.
On-demand tester staffing: This is applicable when the scope of testing includes both a private and public crowd and where the client is looking to hire testers on weekly or monthly basis as retainers, instead of using an output-based model.