* Mesh: this is the normal case. Nodes route data on behalf of others and the node can be reached via a DAO route.
* Leaf: the node does not route data on behalf of others, but others can route data to the node (it has a RPL DAO route).
* Feather: this is a new type of node. A feather node routes data on behalf of others, but does not install DAO routes in the network. Feather nodes allow having a larger number of nodes than the RPL network can sustain in terms of routing tables.
This commit introduces the RPL node types and the feather mode, but does not add support for the leaf node type.
* Added a DAO lifetime timer that sends out a new DAO after half the lifetime of the DAO. This allows implementing DAO route soft state that avoids routing tables in the network keeping stale routes for ever.
* Added ways to schedule a new DAO transmission as well as cancelling an active DAO transmit timer, which makes it possible to do nodes that don't send DAOs.
- Structural modification of RPL data storage.
- Support multiple gateways (multiple DODAG-ID with a unique InstanceID)
- Use Lollipop counters
- Add leaf-only configuration option for RPL
Bugfix :
- Correctly send "Grounded" flag in DIO
300 bytes, as well as cleaner protocol logic.
* Made parent management uniform.
* Simplified the DIO processing.
* Improved the Objective Function API and its documentation.
* Removed redundant code at various places.
* Improved identifier naming.
* Switched visualization from candidate parents to preferred parents only.
* Made DAO ACK transmissions configurable.
* Improved initial ETX guess by using a cached local confidence value.
* Added a periodical rank recalculation function to reduce
the maximum stack depth.
* Increased the Trickle redundancy constant to ensure faster
topological updates.
Extended the objective function API with a callback function that receives link-layer neighbor information.
Throttled DAO transmissions to one per DEFAULT_DAO_LATENCY period.
Added support for an ETX objective function (hysteresis control still lacking though).
Fixed a leak of routes installed by DAOs.
Control that dst_adv_supported is set before sending DAOs.
Improved debugging output.
