Fernando Gont wrote:
On 03/28/2013 01:37 PM, Alexandru Petrescu wrote: [....]There are very many hurdles to a simple straightforward IPv6 address planning for vehicles.1 - At most 2^78 vehicles may exist. There may be not enough space in IPv6 addressing architecture space to uniquely distinguish between all past current and future vehicles.[Disclaimer: I'm completely illiterate when it comes to this whole 'VIN' thing]
Sorry, the VIN stands for Vehicle Identification Number; it's simple one unique identifier of a vehicle with a particular semantics. One can see it at the bottom of the windshield, from outside; and on the identity papers of the vehicles.
That said, IPv6 addresses identify network attachment points. If you
need semantics other than that ("e.g., distinguish between past,
current, and future vehicles"). my take is that you're looking at the
wrong place, possibly at the expense of nodes that do the right
thing.
I did't mean to say do distinguish between old and new vehicles by using an IPv6 address. I meant to say that this VIN mapping to an IPv6 address may be useful not only to newly manufactured vehicles, but also to old vehicles. Third-party vehicle equipment manufacturers (not those who manufacture the vehicle itself) may manufacture and sell a Router to be deployed in the vehicle, to connect the vehicle to the Internet. This Router would be put in new vehicles but also in old ones. (just like one may add e.g. rearview camera to a vehicle which didnt have one at manufacture time). This Router sold by the third-party needs to know what IPv6 addresses are or should there be in the vehicle. With IPv4 it was all simple: just use always the same NAT space 192.168.0.0. Example deployments are from a number of vehicles. But with IPv6 one may need to identify: - whether the use of PI space in vehicle does not do too much route 'churning' in the core of Internet, - whether PA space involving triangular through Home Agent routing is acceptable, and usable for direct vehicle-to-vehicle communications. - and whether ULA space may be recommended. _If_ ULA space may be used then one wonders how to generate one ULA prefix for one vehicle. The RFC ULA does suggest an example algorithm, but it says other algorithms may be possible. Also, the example given has some uncertainties (whose interface EUI-64 should be chosen?). This is one reason we came to generating IPv6 prefixes, and Interface IDs, out of VIN. (it's maybe only me who sends too many emails on this topic, but it is not only me and my co-authors of the mentioned drafts, but there are other people at IETF worked on this VIN-IPv6 topic, presented to f2f IETF meetings, and there exist some IPR activity in that space as well). Alex -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
