Hi Greg, On Sun, 06 Nov 2005 20:10:05 -0800 Greg Daley <[EMAIL PROTECTED]> wrote:
> Hi James, > > I understand the point you're making, and you're > correct, that situations like these often don't get > completely cleared up unless one of the parties > charges to court. > > What we have here, though, is a patent to claim IPR, > not necessarily an actual IPR. While there may not > be anything stopping a patent holder from claiming > the IPR and associated royalties, it's in almost > everyone's best interest to make it widely known that > there is an example of prior art which is well > described and well known to the community (the more > complete a description, the better). > It seems that the Appletalk Address Resolution Protocol method of selecting a node address is very similar, and could possibly serve as prior art for this patent. Christian stated that this patent applies to picking addresses within a narrow number space. The Appletalk number space is only 16 bits for the network address and 8 bits for the node address, which I'd think is smaller than zeroconf address space (169.254/16) I'm guessing this patent suggests a solution for. >From "Inside Appletalk", Copyright 1990, Page 2-8 (page 83 of the PDF if you have it, it used to be available at http://developer.apple.com/macos/opentransport/docs/dev/Inside_AppleTalk.pdf), "Dynamic protocol address assignment" . . . When a protocol stack asks AARP to pick a unique protocol address, AARP first chooses a tentative protocol address for the node. It starts either by choosing an address value from some nonvolatile memory or by generating a random number. If a mapping for that address value already exists in the corresponding AMT, then AARP knows that another node on the network is using this protocol address. It then picks a new random value for the protocol address until it identifies an address that is not in that AMT. Having picked a suitable tentative protocol address, AARP must then make sure that this address is not being used by any other node on the data link. It does so by using the data link to broadcast a number of AARP Probe packets, which contain the tentative protocol address. When a node' AARP receives a Probe packet corresponding to one of its protocol stacks, it examines the protocol address of that stack. If the Probe's tentative protocol address matches the receiving node's protocol address, AARP sends back an AARP Response packet to the probing node. If the probing node receives an AARP Response packet, then the tentative protocol address is already in use and the node must pick a new tentative address and repeat the probing process. If the probing node does not receive a Response packet after a specified amount of time, then it retransmits the probe. If after a specified maximum number of retries the node has still not received a response, then the node___s AARP accepts the tentative address as the node' protocol address. AARP returns this value to its client." (I normally wouldn't cut-and-paste this much text, but you wanted it widely known ... :-) ) Regards, Mark. -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
