HTTP for Globally Distributed Applications

For any distributed application, the network plays a significant role for performance. In the web, the central protocol is HTTP (Hypertext Transfer Protocol) that determines how browsers communicate with web servers and that is used as the basis for REST APIs (Representational State Transfer). For cloud services across different deployment and service models, REST APIs are the default interface for providing access to storage and compute resources, as well as high-level services. Most DBaaS, BaaS, and NoSQL systems provide native REST APIs to achieve a high degree of interoperability and to allow access from heterogeneous environments. This chapter reviews relevant foundations of HTTP and networking with respect to performance and latency, as well as their role in cloud data management. In particular, we will highlight which challenges the standardized behavior of the web caching infrastructure imposes for data-centric services.