Hands-On Microservices with Kubernetes

Dividing and conquering your network

In addition to authentication as part of defense in depth, you can ensure that services talk to each other only if they're supposed to by utilizing namespaces and network policies. Namespaces are a very intuitive yet powerful concept. However, on their own, they don't prevent pods in the same cluster from communicating with each other. In Kubernetes, all the pods in a cluster share the same flat networking address space. This is one of the great simplifications of the Kubernetes networking module. Your pods can be on the same nodes or a different node – it doesn't matter.

Each pod will have its own IP address (even if multiple pods run on the same physical node or VM with a single IP address). This is ...