There are large companies that still have crappy NAT IPv4 only, but my son's car now has static IPv4 and IPv6, with Ethernet in the centre console and WiFi which even handles AirPlay from the iPhone to his sound system...

Yes, I said he was a tad special at times, and I recall when I was young installing a CB radio on my bicycle handlebars and a 12V battery on the rack. I did not have a BMW :-)

So, how is it done..

1. He has an inverter in the boot - sadly some of the kit works off mains. That does not mean we will not eventually make some DC to DC modules and do it all low voltage but for now an inverter is the simplest way. He has run a control switch to the centre console...

2. He is using an apple airport express as the wifi. Yes, he could use a MiFi for all this but that does not provide either Ethernet or AirPlay. The airport is a good wifi (802.11n) and has a 3.5mm jack to connect to the sound system (which is another story involving amps, subs, jigsaws and MDF). It means he can simply select his car on his iPhone or iPad to play music with no wires involved. Steve Jobs would have been proud.

3. He is using a FireBrick FB2700 and a dongle from t-mobile. Yes, not one of our SIMs as he plans to totally abuse their "unlimited data" and knows I would charge him if he used our SIMs. As expected, the dongle "just works" even with factory default config. That gives him an external (dynamic) IPv4 address - which looks un-NATted even, which is nice, but still only one IP and still only IPv4. He has Ethernet from the FireBrick to allow for someone with an in-car laptop, etc.

4. He is then using a VPN tunnel from the FireBrick to the big FireBrick FB6402 in our office. This allows me to route a /28 IPv4 (not greedy) and a /64 IPv6 (which, of course, includes 1337 as part of the address). No NAT proper Internet connection...

The brick does DHCP on the IPv4 space and Router Announcements on the IPv6.

We have, of course, set reverse DNS on both, and whois data for "James's BMW". I have not gone as far as polling google latitude and setting DNS LOC records, but one day maybe...

He has chosen to leave the WiFi open, but we can lock things down if ever needed on the FireBrick (it is a firewall, after all). Basically, if the dongle he has is unlimited, why not have an open wifi on your car!

So, in short, if you are ever on the motorway (perhaps near Addlestone?) near a black BMW and see wifi KE55ARD BMW (not not actually his number plate, though he would like that) then feel free to use the free in-car IPv6 wifi.


  1. Apologies for deleting and reposting - yes, I mis-spelled BMW the first time - classic dyslexia not being able to see it either until several people pointed it out. And my son did not notice either :-)

  2. I did I just didn't tell you cos I was too busy posting it everywhere so I can go get my new iPhone n Friday :)...


    Amongst other pages....

  3. I have changed the word "rape" to abuse after some comments. I am still not clear of the issue as "rape" is an old word meaning abuse, seize, take, and so on, and "abuse" is often used in a modern context for some very negative sexual contexts, but apparently the word "rape" is a problem in spite of its general meaning and, I feel, completely appropriate usage in this context.

  4. ooo, I have a airport express, wonder how practical doing this would be in a mx5! (the boot is tiny as is, it'll be useless with a inverter etc in it)

    RevK - can you take some pics of the install? it'd be nice to see how tidy/untidy it all is...

  5. James agreed to some pics when he has it a tad tidier :-)

  6. With this new found connectivity does it mean that one of the age old BMW problems can be worked around remotely - i.e. are you able to control those mysterious orange flashy lights on the corners from the office, given that the internal control is a rarely purchased option

  7. GazzaK, the whole setup is entirely hidden away either in the sides or underneath the boot floor at the moment, but I'm moving everything to be in the side of the boot between now and the weekend so I'll get a photo then, should fit quite easily into an MX-5 with no trouble. Only slightly more difficult difference being that the battery is in the boot in a 3 Series so you'd need to run power cable to the front in yours...

  8. Of course, this bypasses any of the new fangled government / nanny state porn filtering they are planning and will no doubt be on mobile dongles. :-)

  9. Err, the battery is in the boot in the MX5 too, unless something radically changed in later models?


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