[isf-wifidog] ip allocation fantasies

[Saul Albert]

Hi wifidog,

I'm saul - I work with jo on wireless london. very very impressed at what
you people are doing, and ever so glad to find out you exist! we get 10
wrts delivered tomorrow and will begin experimenting with wifidog,
freifunk firmware and other bits that I have reports from jo about.

In kind-of-response to jo's 'who'se thinking about ip allocation' thing,
I realised I had - in my usual half-baked kind of way, and thought this
would be a good place to start a thread on it.

I hope I understand the problem:

- how can you have a coherant, routable network with sensibly allotted
  addresses without centralised administration or strict controls?

I don't have an answer, but I have a few ideas I've been thinking about -
that we could try given the freedom of starting from scratch :)

Technical centralisation isn't really possible - but if someone is
joining a network - presumably they want to join that network - and
technically interconnect, so some co-operation, even use of a web service
to guide IP allocation can be expected.

There doesn't seem to be a purely technical answer unless there's an
assumption that everything with an ip address would be running
zeroconf-flavoured software, and on a largeish scale, that approach might
not work anyway.  Berlin's mesh is nice in that it allows each olsr node
to allocate ip addresses and route for non-olsr clients, which means that
everyone with a lease can be on the network, without having to do mesh
routing..

So effectively, each freifunk node has a range allotted to it, which it
allocates by DHCP - although it could be done statically... This is quite
a nice approach - as each WRT router has a physical limit - how many
clients it can route for (about 20-30 concurrent users, realistically?)
so there can be some kind of standard IPs per router calculation.. with
optional variance.

Berlin's olsr mesh uses zip-codes as a basis - they get conflicts quite
often as they nothing more than a wiki-page with address layouts

Perhaps the process of ip-allocation can be semi-automated, slow, and
fun. 

What about if when you go to register your new node, you get:

- a map of the city, divided into IP ranges by administrative boundary,
  or some other kind of calculation that everyone would recognise
- the opportunity to enter a zip code and get a relevant range of
  unallocated IPs to use, or if no geocoding info is available, the
  opportunity to enter a lat/long

alternatively...

- a phone number you can call, with a service that reads you out a range
  to use when setting up your node without internet connectivity. (quite
  silly, I know, but we want more uses for our http://uphone.org

The berlinners already have a map of this kind at olsrexperiment.de - but
no nodedb service to semi-automate the ip allocation process.

The problem of routing to the outside world or between free networks can
be solved by tunnelling to some extent - and I suppose that conflicts
will have to be solved as and when networks want to interconnect on an
ad-hoc basis. This seems like a PITA, but then communicating with one's
neighbuors ought to be the point of free networks, surely ;)


Anyone got any suggestions?

Cheers,

Saul.