Ribbon
Ribbon is an inter process communication library
...Ribbon comprises of multiple components some of which are used in production internally and some of which were replaced by non-OSS solutions over time. This is because Netflix started moving into a more componentized architecture for RPC with a focus on single-responsibility modules. So each Ribbon component gets a different level of attention at this moment. APIs that integrate load balancing, fault tolerance, caching/batching on top of other ribbon modules and Hystrix. Load balancer APIs that can be used independently or with other modules. APIs using Eureka client to provide dynamic server list for cloud.