Provided is an end-to-end flow control management for a system on chip interface. As tokens are injected into agents arranged in a computer network, the input point for the token is dynamically changed such that tokens are not always injected into the same agent. Additionally or alternatively, as tokens are injected into a token ring, the tokens are initially not activated until a predetermined event occurs (e.g., after a specific number of hops). Additionally or alternatively, also provided is a free pool manager that can keep at least some high priority slots available by consuming lower priority slots first.