Figure 8. Ajax XML
Roy Fielding proposed a set of principles that constitute a set of standard transmission architectures for the internet in his 2000 dissertation. Fielding (2000) named this architecture Representational State Transfer (REST). REST principles are designed to make communication over the internet efficient and scalable across multiple servers (Vinoski, 2007).
REST enforces standardization of communication. This allows web services written in one language to easily communicate with webservers written in other languages (Vinoski, 2007). REST is also stateless. Servers do not keep information about the clients that are calling them. Being stateless allows clients to transfer between servers seamlessly and allows easy scalability (Fielding, 2000; Vinoski, 2007).
Open data (OData) is a set of web services that allow clients to make queries against databases with a web browser (Krishnaswamy, 2010). This allows companies to make flexible web services that allow clients control how the data will be presented back to them (Krishnaswamy, 2010). Rather than having a set of static web services OData allows clients of the web services to construct their own data interfaces.