Each pod has it's own IP address that is routeable anywhere in the cluster. This makes life much easier because you don't have to do port-forwarding onto the host node.

In all current k8s set-ups, each Minion/Worker node has a subnet that it allocates these Pod IP addresses out of. This isn't a hard requirement necessarily, but it tends to be much easier to make this work, since you only have O(Workers) routes to configure instead of O(Pods), but long term, I think we would rather do away with subnets per node, and simply allocate IP addresses for each Pod individually.