SLIP is the “mostly obsolete” wikipedia:Serial Line Internet Protocol. “On personal computers, SLIP has been largely replaced by the Point-to-Point Protocol (PPP), which is better engineered, has more features and does not require its IP address configuration to be set before it is established. On microcontrollers, however, SLIP is still the preferred way of encapsulating IP packets due to its very small overhead.”

Contiki uses SLIP to bridge the wireless IPv6 network onto a PC via a USB connection. So with your Zigduino plugged into your PC, and the right software running on each, traffic from the wireless IP network can reach your site-wide Ethernet network and potentially beyond.

On Zigduino, there is only one UART exposed. This means we have to choose between reading debug messages and connecting to our PC via SLIP. This change is exposed by adding “WITH_SLIP=1” to the makefile or command line for any particular project. Projects made “WITH_SLIP” will expect to talk to a slip tunnel on the PC side.

Speaking of the PC side… In order for SLIP to work, something on the host PC has to be listening. Using Instant Contiki, the 'tunslip6' will do this. Running it in Linux creates a 'tun0' interface which gives the connected Zigduino an address of aaaa::1 on your local network.

First, built the tunslip6 tool. This works without modification on Instant Contiki.

 
$ cd tools 
$ make tunslip6 

Now make and upload the border router itself. Be sure to include “WITH_SLIP=1” to turn on slip for this node, and “WITH_WEBSERVER=0” to exclude a web server from this node.

 
$ cd examples/ipv6/rpl-border-router 
$ make TARGET=avr-zigduino savetarget 
$ make WITH_SLIP=1 WITH_WEBSERVER=0 -j10 
$ make upload AVRDUDE_PORT=/dev/ttyUSB0