New RF protocol - RFM69 modules and generic gateway

I’m developing my own nodes with RFM69 modules and decided to not use the rfm12 JeeLabs library and use a RFM69 specific one to gain added functionality of the new hardware. This will make new RF nodes incompatible with the older.

So i’m building a generic gateway RF->TCP that can pass pairs of name->value data to the emoncms input API.

Now need to create a message payload format and re-think the concept of node id to support any number of devices.
1 - I’m thinking on using msgpack: http://msgpack.org/.
2 - Use serial number / guid / mac, or just some setup phase pre-roll authentication?
3 - Size limitation, each data package on the air must be < 63bytes.
4 - Large multi-package messages is a desired option.
5 - Support for out-band data like RSSI, battery level, etc
6 - Support bidirectional data for remote config / firmware update?

Any one want to give inputs on this and about other data encoding formats to use that can be implemented on an arduino?

I’m curious if you had considered the LowPowerLab drivers?

I’m not an expert but have been experimenting with them for the past few months.

Yes, I’m using their drivers. They are nice, but still need to dig on multi package support.