ble-ipv6

BLEach: a fully open-source IPv6-over-BLE stack for Constrained Embedded IoT Devices

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 extenstion implements BLEach, a fully open-source IPv6-over-BLE stack for Contiki. BLEach in Contiki-NG can be used for node (BLE slave) devices.

It was developed by

Michael Spoerk, Graz University of Technology, michael.spoerk@tugraz.at, github user: spoerk

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 connection slave

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

Modules

The IPv6-over-BLE stack comes with the following modules:

BLE radio

The implementation of the BLE radio for the TI CC26xx platform is implemented in arch/cpu/cc26x0-cc13x0/rf-core/ble-cc2650.c and arch/cpu/cc26x0-cc13x0/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 arch/cpu/cc26x0-cc13x0/rf-core/ble-l2cap.c. Besides implementing rudimentary L2CAP support, this module handles fragmentation of large IPv6 packets.

Using BLEach

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 and border routers.

IPv6-over-BLE node (BLE slave)

To enable IPv6 over BLE, the project conf 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
#define NETSTACK_CONF_MAC                   ble_l2cap_driver

#define RTIMER_CONF_MULTIPLE_ACCESS       1

/* 6LoWPAN settings */
#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.