JeeMesh is a mesh protocol in development at HacDC to extend the
[JeeNode](http://cafe.jeelabs.net/lab/jn5/)
[RF12](http://cafe.jeelabs.net/sw/library_-_rf12/) low power wireless
protocol for mesh routing, packet fragmentation, and (more) reliable
delivery.

RF12 has the following limitations:

- up to 30 nodes (typically 26 nodes and 4 servers/gateways)
- MTU 66 bytes
- range of about 30' to 50' at 915mhz

We intend to extend these limits somewhat:

- MTU 1023 bytes
- range up to 200' by routing through up to four nodes on a mesh

A 16 bit header is added using the first two bytes of the RF12 packet
data as follows:

- 5 bits for original source node
- 5 bits for final destination node
- 2 bits for ttl
- 4 bits for fragment sequence

This allows us to reconstruct 1024 byte JeeMesh packet from 16 64-byte
packet fragments. We further add another 8 bit header to the first
packet fragment, reducing the MTU to 1023 bytes:

- 4 bits number of fragments
- 4 bits packet type

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