Comparing REST, SOAP, Socket and gRPC in computation offloading of mobile applications: An energy cost analysis

There has been a high concern regarding the energy saving on mobile devices recently, for mobile devices have been performing increasingly complex tasks over time. The computation offloading is one of the most popular techniques used by developers as an effective way of saving energy on mobile devices, which consists on executing complex tasks in external servers with different purposes including save energy. Deciding towards offloading certain tasks requires to understand the influence of the amount of data, amount of computation, and the network profile. Several studies have investigated the influence of different wireless flavours, such as 3G, 4G and wifi, but no study has investigated the influence of the communication choices on the energy cost. Therefore, in this paper, we present an experiment we conducted to evaluate the energy consumption of different communication protocols and architectural styles, namely REST, SOAP, Socket and gRPC, when executing algorithms of different complexities and different input sizes and types. Results show that local execution is more economic with less complex algorithms and small input data. When it comes to remote execution, REST is the most economic choice followed by Socket. Moreover, our data show that computation offloading can save up to 10 time as much energy when compared to local execution for some executions configurations.