I’ve started reading John Day’s Patterns in Network Architecture and during the first pages it makes strong references to Saltzer’s 1982 paper. Why would I bring this up? Well, I just heard Surprisingly Awesome‘s episode on Postal codes where they deal with two countries (Lebanon and Mongolia) with almost non-existent addressing plans. Here is what an addressing plan should give you:
- a name identifies what you want,
- an address identifies where it is, and
- a route identifies a way to get there
Day makes the case that we usually use that address of a network element in the same way that we use its name also which is an error, since by moving an element elsewhere in the network, we need to change its name also. You on the other hand do not change your name when you change your home address. You used to change your phone number, but even that has become equally portable.
In places where no stable addressing system exists the courier is required to build a mental representation of the routes in their area of delivery, based on landmarks, trees, neon signs, whatever can help to make the delivery. In Mongolia this is solved differently: When something arrives at the post office, they call you back and you go and pick it up.
Enter the NAC. What is it exactly? It is an effort to map longitude and latitude to a more memorable representation using the base 30 number system using digits and capital letters. Borrowing from Wikipedia, the NAC for the centre of the city of Brussels is HBV6R RG77T. Compact, accurate, but not quite memorable.
what3words seems to be a service set to solve this since with their solution a unique combination of just 3 words identifies a 3m x 3m square anywhere on the planet. For example, roughly the same place as above is described as october.donor.outlined. I admit, this is much easier to type in a GPS (or tell Siri).
However, I am still surprised that nobody ever thought of using IPv6 for this (maybe somebody has? Please tell me). Given the abundance that the 128bits give us, we could have indexed every square meter on the surface of the planet and make it addressable. Oh, the directories we could have built on top of that. But I have no fear. It is quite probable that much of the inhabited First World’s surface will be pingable in the foreseeable future. The IoT will make sure of that.