IPv6 over BLE

Overview

In 2015, the IETF released the RFC 7668 that specifies how IPv6 packets can be exchanged using BLE connections (IPv6 over BLE). This Contiki-NG extenstion implements BLEach, a fully open-source IPv6-over-BLE stack for Contiki-NG. Currently, BLEach can be used for IPv6-over-BLE node devices that act as a BLE slave device.

It was developed by

This IPv6-over-BLE stack is presented and evaluated in the paper: BLEach: Exploiting the Full Potential of IPv6 over BLE in Constrained Embedded IoT Devices, ACM SenSys’17.

Features

This implementation includes:

  • IPv6-over-BLE node implementation compliant to RFC 7668

    • connect to a single IPv6-over-BLE border router

    • maximum IPv6 packet length of 1280 bytes

    • BLE L2CAP channels in LE credit-based flow control mode

  • BLE link layer support for version 4.1:

    • BLE advertisement

    • BLE initiating

    • BLE connection slave

    • BLE connection master

It has been tested on the TI CC2650 SensorTag and the TI CC2650 LaunchPad hardware.

Modules

BLEach comes with the following modules:

BLE radio

The implementation of the BLE radio for the TI CC26xx platform is implemented in arch/cpu/cc26xx-cc13xx/rf-core/ble-cc2650.c and arch/cpu/cc26xx-cc13xx/rf-core/ble-hal/*.[ch]. These files contain all the hardware specific code for supporting BLE as a link layer.

BLE L2CAP layer

The L2CAP LE credit-based flow control support is implemented in os/net/mac/ble/ble-l2cap.h and os/net/mac/ble/ble-l2cap.c. Besides implementing rudimentary L2CAP support, this module handles fragmentation of large IPv6 packets.

Using BLEach

A simple IPv6-over-BLE UDP-client is included under examples/ble/ipv6-client.

For IPv6-over-BLE support, IPv6 needs to be enabled and RPL needs to disabled in Contiki-NG:

MAKE_MAC = MAKE_MAC_BLE
MAKE_NET = MAKE_NET_IPV6

Currently, BLEach is only available for the Texas Instruments CC2650 hardware platform.

The following sections describe how to configure BLEach for IPv6-over-BLE nodes.

IPv6-over-BLE node (BLE slave)

To enable IPv6 over BLE, the project configuration needs to contain:

#define PACKETBUF_CONF_SIZE                  	1280
#define QUEUEBUF_CONF_NUM                       1
#define UIP_CONF_BUFFER_SIZE                 	1280

#define NETSTACK_CONF_RADIO             	ble_cc2650_driver

/* 6LoWPAN settings */
#define SICSLOWPAN_CONF_MAC_MAX_PAYLOAD      	1280
#define SICSLOWPAN_CONF_COMPRESSION          	SICSLOWPAN_COMPRESSION_HC06
#define SICSLOWPAN_CONF_COMPRESSION_THRESHOLD   0  /* always use compression */
#define SICSLOWPAN_CONF_FRAG                    0
#define SICSLOWPAN_FRAMER_HDRLEN                0

/* network stack settings */
#define UIP_CONF_ROUTER                         0
#define UIP_CONF_ND6_SEND_NA 			1

The following optional parameter can be used to configure that BLE advertisement behaviour:

#define BLE_CONF_DEVICE_NAME					"TI CC26xx device"
#define BLE_CONF_ADV_INTERVAL					25

BLE_CONF_DEVICE_NAME holds the device name that is used for advertisement, BLE_CONF_ADV_INTERVAL specifies the used advertisement interval in milliseconds.