Hello, Dear diary, on Mon, Nov 04, 2002 at 10:43:32PM CET, I got a letter, where Bob Hinden <[EMAIL PROTECTED]> told me, that... > Even though there is no consensus on how site-local addresses should be > used, I think there is enough people who want to use site-local that it is > reasonable that the w.g. should continue trying to flesh out site-local > usage as well as pitfalls of usage. ..snip.. > I believe this approach should help provide the larger community (e.g., > vendors, ISP's, enterprise operators, etc.) the information they need to > make an informed decision on the usage of site-locals.
I would like to present here one possible scenario of site-local usage, which I believe wasn't mentioned here yet. It's not a real-world usage example yet, but it may not be so far from that point. First, let me introduce you to the environment briefly. We're trying to design a possible IPv6 network addressing architecture for a non-commercial metropolitan (Prague, CZ) network based on wireless connections between nodes. One of the driving ideas was to provide a connection to that network for anyone without any charge, only for the price of the equipment (given that you'll be able to come along with the admin of the node you want to connect to). Also, connectivity to the internet should be provided by the network in some way - but the basic principle here is to give anyone a free choice, which provider he will use. Thus, various members of the network could be connected to the internet by various providers (over the network itself, as the providers are represented by own nodes in the network). Also, the network's internal topology is totally independent on points' choice of provider. Note that this is a running setup already - it's around 37 to 48 working nodes now (the current status is at http://czfree.net/monitor/), and one to three internet providers having own nodes in the network. It's running on IPv4 now, though. Now, the internal addressing is done just by giving out addresses from the 10.0.0.0/8 range, and NATing it on the provider nodes. For IPv6, you could: * Request own IPv6 space from a LIR - but that won't work out. The addresses which matter to the global internet are those which are being used by the providers. And none of the providers is going to advertise the whole network, since it would donate bandwidth even to people who aren't its clients. * Just use directly the addresses your provider will give you - but that won't work out as well. It would cause total mess in the topology, since the nodes inside of the network wouldn't be numbered consistently. Also, a lot of the nodes are probably not going to have any internet connectivity at all, thus they would have no address. * Use some global private address block; then assign the internet connected nodes also provider addresses (and let the underlying routing protocol handle the routes propagation etc). However, we are not aware of any such a prefix being available these days. * Use site-local addressing; then assign the internet connected nodes also provider addresses (and let the underlying routing protocol handle the routes propagation etc). This comes out as a natural choice, as it probably fully fulfills our requirements and it is relatively elegant solution. We think that this use of site-local addressing is fully legitimate here. What do you think? Or what alternative solutions would you suggest to this problem? Kind regards, -- Petr "Pasky" Baudis . weapon, n.: An index of the lack of development of a culture. . Public PGP key && geekcode && homepage: http://pasky.ji.cz/~pasky/ -------------------------------------------------------------------- IETF IPng Working Group Mailing List IPng Home Page: http://playground.sun.com/ipng FTP archive: ftp://playground.sun.com/pub/ipng Direct all administrative requests to [EMAIL PROTECTED] --------------------------------------------------------------------
