Quoting from the Egenra official announcement:
Egenera Inc., a global leader in datacenter virtualization architecture, today announced that the U.S. Patent and Trademark Office has issued U.S. Patent No. 7,174,390 entitled, “Address resolution protocol system and method in a virtual network.”
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Address Resolution Protocol (ARP) within conventional Ethernet networks associates server and application IP addresses with their Ethernet addresses. In systems such as the Egenera BladeFrame system that emulate Ethernet semantics on a high-bandwidth, low-latency, point-to-point fabric, virtual circuits in the fabric direct traffic flow. Typically, it is necessary to further convert Ethernet addresses into virtual circuit numbers whenever traffic is sent—adding an extra table look-up for each transmission. Egenera’s invention obviates the extra step by combining the virtual circuit table with the ARP table, lowering latency and processing overhead…