Ideas for Hacks
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Sputnik as a meshed network
It might be an interresting idea to use the tags as wireless routers. Since the pic controllers have rather little memory, a full TCP/IP stack is most likely impossible.
However it might be possible to implement a very stripped down version of X.25 with small packets.
What the tag would have to do would be about the following:
- Send some unacknownledged hello packets in more or less defined intervalls.
- Have some commands like "list last recieved hello packets".
- The possibility to connect streams to the device and have a very simple command line interpreter which can understand commands like "connect me to this other node". The commands could be single character, just like with old monitor programms. The interpreter would have to work with only a few bytes of RAM per connection.
So essentially you would connect from node to node. Definitely not a very luxurious system like OLSR, but it might do the job. As the origin of the stream would be hidden at the first hop, it's also moderately anonymous.
There is also a cultural aspect to this. It's using technology designed for surveillance do provide anonymous communication. :)
Ram usage
An X.25 connection needs about 2 bytes for the counters as well as some space to store the addresses of both endpoints. Seven Bit per address should be good enough as they don't have to be network unique, but only locally unique. Perhaps we could use 3 bits for the computer and 4 for the connection ID. This would only require another 1 Byte per connection. So we'd have about 3 Bytes overhead, perhaps another byte for the command interpreter, so we have 4 Bytes plus the packet buffer. So 8 Bytes per connection might be feasible with good programming.
Nike+iPod sniffing
Nike and Apple desiged a shoe<->iPod communication system, using a HW very similar to the Sputnik. The system is described here and disassembled here.
Applications to think about
- Exchange of vCards
- Broadcast-Messages
- Adressed Messages
- Synchronisation of time
