Impact of Service- and Cloud-Based Dynamic Routing Architectures on System Reliability

Various kinds of dynamic routing architectures are used in today’s service- and cloud-based architectures, including sidecar-based routing, routing through a central entity such as an event store, or ar- chitectures with multiple dynamic routers. So far, the impact of these architectures on system reliability has not been studied. We propose an analytical model of request loss during router and service crashes, as well as an empirical validation of that model. The comparison of the empir- ical data to the predicted values by our model shows a low enough and converging error rate for using the model during system architecting. Our model predicts that, having the same crash probability, decentral- ized routing results in losing a higher number of requests in comparison to more centralized approaches. These results provide important new in- sights when making architectural decisions regarding dynamic routing. To the best of our knowledge, our study is the first to empirically study the reliability trade-off in such architectural decisions.