The present disclosure is directed to Quality of Service (QoS) and handshake protocols to facilitate endpoint bandwidth allocation among one or more agents in a Network on Chip (NoC) for an endpoint agent. The QoS policy and handshake protocols may involve the use of credits for buffer allocation which are sent to agents in the NoC to compel the acceptance of data and the allocation of an appropriate buffer. Messages sent to the agent may also have a priority associated with the message, wherein higher priority messages have automatic bandwidth allocation and lower priority messages are processed using a handshake protocol.