Design Patterns for RESTful Communication Web Services

In recent years, REST (Representational State Transfer) has received much attention for designing scalable web services in various domains. There is an increasing interest on its application to real-time communication web services. Based on a case study of CSTA services, we found that communication services exhibit a combination of complex message exchange and stateful behavior patterns, including multi-states, two-way interaction, event-driven, multi-resources, multi-responses and session management, that need to be modeled properly within the framework of REST. To address these challenges, we propose three REST design patterns: session, event subscription and relationship using REST composition. This approach leads to a systematic one-to-one transformation from CSTA to REST. We hope such a study on a concrete use case can contribute to a better understanding of REST and lead to a seamless convergence of communication services with the infrastructure of the Web.