RHT uses the Arduino platform for its solar thermal system sensors. Given that many sensor networks will be built using IPv6 in the future, RHT has developed an IPv6 Ethernet library.  This work is offered to the arduino community for its collective benefit.

The official Arduino Ethernet Shield is based on the WizNet 5100 chip, which implements the IPv4 protocol stack in silicon.  As a consequence, the Arduino Ethernet Shield cannot be used to implement an IPv6 stack.  

To implement an IPv6 stack, it is necessary to use a shield based on hardware that permits the management of IP and Ethernet layer functions.   Shields based on the MicroChip ENC28J60 chip (such as those sold by Ekitszone and Nuelectronics) are suitable for the implementation of an IPv6 or dual IPv4/IPv6 stack.  This approach requires the TCP state machine to be implemented in software and results in more complex arduino code.

The RHT IPv6 libraries are based on the EtherShield library developed by Pascal Stang, Xing Yu, and Guido Socher.  The earlier ipv6etherhield developed by Guenther Hoelzl was tested but found to be unstable and would not compile on the most recent versions of the Arduino Integrated Development Environment (IDE). Thank you to all of those whose work was used as the basis of this effort.

The RHT IPv6 libraries are availbale for both the Arduino Mega and Arduino UNO platforms.  RHT recommends that the Ekitszone Ethernet Shield for Arduino Mega be used with the Arduino Mega, and that the Ekitszone Ethernet Shield for Arduino UNO be used with the Arduino UNO.  

The Ekitszone Ethernet Shield for Arduino UNO can be used with the Arduino Mega if the connection of the ENC28J60-based shield to the Arduino Mega is modified. Pins 10, 11, 12 and 13 of the ENC28J60-based shield must be bent out (or cut), and these pins of the shield must be then connected (by adding wires) to the Arduino Mega pins 53, 51, 50 and 52 respectively.

The RHT IPv6 library supports IPv4 and IPv6 Unicast addresses (manually configured by user by editing the sketch)

• Address Resolution Protocol (ARP) for IPv4.
• ICMPv6 Neighbor Advertisement messages are provided in response to ICMPv6 Neighbor Solicitation messages.
• ICMPv4 Echo Reply messages are provided in response to ICMPv4 Echo Request (ping) messages.
  
• ICMPv6 Echo Reply messages are provided in response to ICMPv6 Echo Request (ping) messages.
• An HTTP page is provided in a single packet, in response to an HTTP Request.
• IPv4 and IPv6 stacks can be individually enabled.

• ICMPv6 Neighbor Advertisement messages are provided in response to ICMPv6 Neighbor Solicitation messages.
• ICMPv6 Echo Reply messages are provided in response to ICMPv6 Echo Request (ping) messages.
• An HTTP page is provided in a single packet, in response to an HTTP Request.

Potential Applications:

• A simple web server to confirm ipv6 connectivity when testing IPv6 network configurations.
• An HTTP sensor that can be polled using HTTP Requests.
• An HTTP controller that can receive HTTP messages to turn devices on or off.

To use the RHT IPv6 libraries:

• Download the RHT Dual Stack IPv4/IPv6 Library for the Arduino Mega or the RHT IPv6 Library for the Arduino UNO and copy the library files into the Arduino IDE libraries directory,
• Open the Arduino IDE (Arduino IDE version 0022 is recommended, we have had problems uploading to the Arduino Mega platform with the Arduino IDE version 1.0.1), and load the example located in the example sub-directory under the RHT IPv6 library sub-directory.
• Edit the IPv6 addresses, and the http data to be returned, at the top of the Arduino .pde file as appropriate to your environment.
• If you plan to run more than one Ethernet-connected Arduino on the same link, be sure to configure distinct Ethernet MAC addresses, IPv6 unicast addresses, and IPv4 addresses for each Arduino.
• Compile, Upload and Run your Arduino sketch.
• Note that some virus scanner programs will block IPv6 packets by default - you may have to enable IPv6 on the virus scanner, or turn off the virus scanner for your initial tests to work.
  
• Use a browser to access your IPv6 Arduino with a URL such as http://[2001:0470:9bca:0815::1234]/.

Questions and comments on the RHT IPv6 library should be addressed to ipv6@reflectiveheat.com.  

We offer expertise with solutions including;

• XBEE wireless radios, 
• DS18B20 temperature sensors, 
• LCD displays, 
• serial interfaces,
• ethernet interfaces (IPv4 and IPv6),
• PHP server data management solutions.