Task 5: Using network devices

RIOT's Networking architecture

Network devices are accessed through netdev driver API

It has capabilities for receiving and sending data and for getting and setting options or states.

Note inclusion of netdev modules in the Makefile

USEMODULE += gnrc_netdev_default
USEMODULE += auto_init_gnrc_netif

Virtual network interface on `native`

Use tapsetup script in RIOT repository:

sudo ./../RIOT/dist/tools/tapsetup/tapsetup -c 2

Creates
- Two TAP interfaces tap0 and tap1 and
- A bridge between them (tapbr0 on Linux, bridge0 on OSX)
Check with ifconfig or ip link!

Task 5.1 -- Your first networking application

Run the application on native: make all term PORT=tap0
Type help
Run a second instance with make all term PORT=tap1
Type ifconfig on both to get hardware address and interface number
Use txtsnd command to exchange messages between the two instances

Task 5.2 -- Use your application on real hardware

Compile, flash, and run on the board BOARD=samr21-xpro make all flash term
Type ifconfig to get your hardware addresses
Use txtsnd to send one of your neighbors a friendly message