Monday 12 August 2013

Find me in Paradise

After a bit of a hiatus I’m back – the break was enforced by an increased workload due to both the demands of getting the new service centre open, and of getting married. Of the two the wedding was probably the least stressful as I’m now getting pretty used to planning complex operations and then having to trouble shoot on my feet.

Flying out to my honeymoon on a new Emirates Airbus A380-800 was a delight – the economy cabin is more comfortable than some business classes, but the in-flight entertainment system blew me away.  The sheer range of entertainment options meant that I had trouble sleeping despite the great seats, and the console included power outlets for laptops as well as allowing me to plug my iPhone into a USB socket (with a little bit of trepidation, as I really didn’t want to have to take over flying the plane) for a quick charge. It’s refreshing that the decrepit entertainment systems that most planes still carry are being replaced at last – the last generation are getting on for ten years old, so it’s a bit like moving from a very sluggish installation of Windows XP straight to the slick interface of Windows 8. You may laugh, but I’ve always wanted to see my house from the plane, but as I live directly under the flight path the only way to do this would be from the cockpit; on my return flight I got to use the downwards facing camera, one of three external cameras, to zero in on my very own roof as we passed overhead.

Before setting off I did a little research and downloaded a few apps to help us explore Dubai (18 hour stopover) as well as a few offline maps of the Seychelles using the excellent MapsWithMe App. This free App is simply brilliant as you can select countries and download detailed maps before you leave, and then use it without relying on a data connection. This is something you can also do with Google Maps, but in practice it’s means zooming in to the required levels of detail and then copying dozens of map tiles to cover an area, and to describe it as clunky would be to flatter it greatly.

MapsWithMe worked superbly once we arrived in the Seychelles on our island hopping holiday, but I did discover something about my Wi-Fi-only iPad which surprised me. While it worked well while I was connected to Wi-Fi, as soon as I left my hotel it would be unable to locate me on the map. While connected I did some research and found out that the iPad’s GPS module is part of the 3G board, so the Wi-Fi only iPads use Wi-Fi to locate themselves. In a city where there are plenty of Wi-Fi signals to browse this means that the device can easily position itself accurately, but out in the islands signals are few and far between, and it gets lost pretty easily.

By chance during my stay at this particular hotel the wireless router failed, and I lent a hand in diagnosing the problem. When the hotel replaced the router for a new one I was surprised that despite it using the out-of-the-box identifier of ‘Linksys’ my iPad still knew exactly where it was. This got me thinking. A router, like all network devices, has something called a MAC address which is in theory unique. So how did my iPad know that the new MAC address was located exactly at our hotel in Praslin Island? Router’s don’t have GPS receivers, and the ISP couldn't as far as I could see work out exactly where the router was either even if it were using postcode look-ups. It seemed to me that the only way it could know my position so accurately is if another device connected to the same router was telling it. This seemed a little unlikely, but it also seemed to be the only logical answer to this mystery, so now I’m back I decided to see if I was right, and after a little digging it turns out that I had hit the nail on the head. 

Simply put, as soon as an apple device with GPS identifies a wireless signal it transmits its position and the unique MAC address back to Apple who store this information in a database. So even if I want to keep my router’s location a secret and turn off Apple’s location services on my own devices, Apple can still locate the router as soon as the first iPhone without location services disabled sees my wireless signal, and to clarify, it doesn't need to connect to my router, it only needs to be able to see the station identifier.

In itself this still isn't really that sinister as lots of people know where my router is; my ISP, my neighbours, Apple… but now imagine a government wants to combine this location database with something really useful, such as a router firmware enhancement which logs and transmits all MAC codes that connect to a router to, say, the NSA, and you start asking yourself if something that useful to the NSA won’t already be out there. And if Prism has taught us anything, the answer is probably yes.