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Adding GPS location to IPv6 header
On Mon, Nov 26, 2012 at 5:46 PM, Harald Koch <chk at pobox.com> wrote:
> On 26 November 2012 17:36, William Herrin <bill at herrin.us> wrote:
>> Suppose you have a large single-owner mesh network, such as a folks
>> walking around with cell phones. If you want them to have a stable
>> layer 3 address (and you do) then you're handling what amounts to /128
>> routes for tens of millions of devices. If you can guarantee that any
>> packet *to* that address also contains a rough geographic location
>> then you can discard any routes internally once they're more than a
>> short geographic distance from the origin and route on the geography
>> until you're close enough to find a specific /128 route. Tens of
>> millions of routes is no problem if no single router needs to know
>> more than a few thousand of them.
>> By putting geographic location at layer 3, you're also handling it end
>> to end which means you don't need a stateful border device to track
>> the current location of all of those /128 routes. The device itself
>> doesn't need to add location if it doesn't have the data; it's good
>> enough for the receiving tower to attach a rough location.
> This also naively assumes that wireless network topology correlates with
> geographic location. Any radio engineer (or cell phone user) can explain
> why that doesn't work.
No. It assumes that the /128 route propagates far enough that every
router (read: radio tower) operated by the service provider within the
rough geographic locality has that route so that wherever the packet
lands in the general area, it can make its way to the origin router
currently talking to the device. It makes no assumptions about the
particular path or paths between those two routers which could be
terrestrial radio, satellite, wired or even a VPN across who knows
what Internet path. It does set a requirement on the network
architecture that at least one such path must exist: network
partitions appear deadly to this architecture.
I'm not saying this is a good idea. I'm just saying it's a legitimate
topic for research and investigation which, if it shows any promise,
would support the addition of a geolocation option header to IPv6's
layer 3. By contrast, Ammar's other rationale for why to put it there
(common interest at layer 7) aren't legitimate reasons for adding data
to layer 3.
William D. Herrin ................ herrin at dirtside.com bill at herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
Falls Church, VA 22042-3004