A growing range of commercial management tools provide the ability to control VM sprawl across disparate hypervisors. In addition, the hypervisor platform vendors -- such as , and Microsoft, and public cloud services providers have made this the principal feature of their various management tools. Sometimes referred to as "instance management," it's a feature that is lacking from traditional SOA governance tools.

The mash-up quagmire

Traditional SOA-style development is top-down. It requires considerable upfront architectural design, factoring functional primitives into platform-independent, loosely coupled service contracts that are exposed to developers through open Web services standards. It often also includes a core service catalog, such as Universal Description Discovery and Integration (UDDI) to broker abstract service contracts, as well as tools and platforms that support key interface standards such as Web Service Definition Language (WSDL) and Simple Object Access Protocol (SOAP).

By contrast, cloud services encourage a grassroots style -- often known as Web 2.0, Web Oriented Architecture or Representational State Transfer (REST) -- of service provisioning, development and management. Anyone with a credit card can sign up for and start accessing cloud services, which may be totally redundant with applications that their companies have deployed internally.

By the same token, anyone with a browser can mash up available cloud service components into applications that may deviate significantly from corporate-standard design patterns -- and probably lack the stringent security expected from enterprise-grade services. In the REST paradigm, UDDI, WSDL, SOAP and other WS-* standards are conspicuous in their absence. So it's no surprise that the phrase "mashup governance" gives some SOA professionals anxiety fits and causes others to double over with laughter.