Memory arbitration system and method having an arbitration packet protocol

A method of responding to a read request in a system memory having a responding hub and at least one interposing hub through which a read response is transmitted on a data path of the interposing hub, the method comprising:

• retrieving read data from a memory device coupled to the responding hub and preparing a read response including the read data;
• generating an arbitration packet including data indicative of a data path configuration for the read response, the arbitration packet having a plurality of 8-bit bytes including at least one byte including data used by the interposing hub to distinguish the arbitration packet from a read response;
• providing the arbitration packet and the read response to the interposing hub, the arbitration packet provided prior to the read response;
• and
• enabling a data path for the read response in the interposing hub in accordance with the data of the arbitration packet.