US Patent 7500031 Ring-based cache coherent bus

Managing data traffic among three or more bus agents configured in a topological ring includes numbering each bus agent sequentially and injecting messages that include a binary polarity value from the bus agents into the ring in a sequential order according to the numbering of the bus agents during cycles of bus agent activity. Messages from the ring are received into two or more receive buffers of a receiving bus agent, and the value of the binary polarity value is alternated after succeeding cycles of bus ring activity. The received messages are ordered for processing by the receiving bus agent based on the polarity value of the messages and a time at which each message was received.