Network transfer costs are a reality of life in many cloud environments. For AWS at least, this has fallen in the range of $0.09 / GB for egress traffic and $0.02 / GB for traffic that crosses zone boundaries (although it can be a lot more complex).
As workloads have migrated to microservices, the impact and importance of network transfer costs have changed substantially. Platforms like Kubernetes, ECS or Nomad make it incredibly easy to spin up new services, and clusters are frequently spread across availability zone boundaries. This has made network transfer costs:
Substantially larger in magnitude and subject to large swings due to increased service to service communication and
Increasingly opaque since it’s hard to map network consumption to a distributed service that may run across tens or hundreds of instances.
Flowmill provides a dashboard explicitly designed for network costs. This interface shows you the services that generate the most cross zone and egress traffic in your environment and lets you to drilldown to see the destination services with which they communicate. Services here will include both internal services you run and operate as well as managed services run by a cloud provider or 3rd party platform.