Understanding IPv6's Potential for IoT: The IoT6 Research Project

 

The conclusions presented in our previous article (The Case for IPv6 as an Enabler of the Internet of Things) were the result of a three-year project dubbed IoT6, supported by the European Commission. Though the main outcomes of the project are the recommendations on exploiting IPv6's features presented in our first article, we thought it useful and informative to provide context for how we arrived at those recommendations, discuss related findings and mention representative use cases.

The IoT6 project really focused on exploiting the potential of IPv6 (Internet Protocol version 6) and related standards such as 6LoWPAN (IPv6 over Low power Wireless Personal Area Networks), CoRE (Constrained RESTful Environments), COAP (Constrained Application Protocol), etc., to overcome current shortcomings and fragmentation in the development of the Internet of Things (IoT).

The project's main objectives were to research, design and develop a highly scalable, IPv6-based, service-oriented architecture to achieve interoperability, mobility, cloud computing integration and intelligence distribution among heterogeneous smart things, components, applications and services.

This subject's potential has been researched by exploring innovative forms of interactions such as:

• Information and intelligence distribution;
• Multi-protocol interoperability with and among heterogeneous devices;
• Use of identifiers in conjunction with IoT devices and IPv6;
• Device mobility and mobile phone networks integration, to provide ubiquitous access and seamless communication;
• Cloud computing integration with Software as a Service (SaaS);
• IPv6 – Smart Things Information Services (STIS) innovative interactions.

Designing an IPv6-based architecture

The IoT6 project designed and tested a Service-Oriented Architecture (SOA) based on IPv6 to integrate heterogeneous IoT components.

The project also developed a software and communication stack based on IPv6/6LoWPAN at the network layer, combined with CoAP/HTTP (Hypertext Transfer Protocol), JSON (JavaScript Object Notation) and oBIX (Open Building Information Xchange), which has been deployed in four environments: Contiki-motes, OSGi-Gateway, Digcovery-server and Mobile-phone.

These implementations provide the functionalities of IPv6 connectivity and open service layer. Both implementations support IoT6 interoperability in heterogeneous networks such as wireless sensor devices or legacy technologies, including BACnet and KNX. (BACnet is a data communication protocol for Building Automation and Control Networks. KNX is a standardized, OSI-based network communications protocol for "smart" buildings.)

The IoT6 open service layer is based on a scalable architecture that supports discovering, registering and looking-up services and resources of heterogeneous and ubiquitous IoT devices. For the architecture, we developed four main elements: global Digcovery, local Digrectory, smart object and mobile Digcovery. Global Digcovery is a centralized platform that enables any IoT client to look up IoT resources and services through standard interfaces such as HTTP and CoAP.

In a local domain, each Digrectory registers fine-grained descriptions of the IoT resources and services following the scalable DNS (Domain Name System) infrastructure to support distributed local queries. The smart object implementation enables the autonomous registration and M2M (machine-to-machine) access of resources and services available from IoT devices using mDNS and CoAP protocols, respectively. (mDNS stands for the multicast Domain Name System, which resolves host names to IP addresses within small networks that don’t include a local name server.)

The IoT6 project also implemented and provided other transversal functionalities such as semantic description, context-aware search and communication interfaces to achieve a unifying architecture. First, we provided a homogeneous semantic description based on CoAP links, oBIX data format and JSON message structure to support interoperability in heterogeneous IoT domains. Second, we integrated the MongoDB (an open-source document database) search engine in the proposed architecture to support a scalable context-aware look-up based on geo-location, domain and type of resources. Third, we provided the communication interfaces to enable interoperability between the proposed elements with heterogeneous IoT things and clients.

The proposed architecture is compatible with existing protocols based on standardized technologies such as IPv6 and DNS. Moreover, the architecture supports the integration of heterogeneous IoT devices including 802.15.4 sensors, RFID tags, building actuators and mobile phones. The architecture also provides an open service layer to interact with end-user applications through standardized interfaces such as web services (HTTP), and constrained applications (CoAP).

Legacy protocol integration

The IoT6 project researched the potential of IPv6 addresses as identifiers for heterogeneous IoT devices. It demonstrated that part of the address space associated with each routable IPv6 address could be used to address non-IP end devices from legacy deployments, such as KNX and BACnet. This mechanism was pioneered by UDG, and further specified and fine-tuned by IoT6. UDG is an IPv6-based multi-protocol control and monitoring system using IPv6 as a common identifier for devices using legacy protocols.

The project also developed a lightweight module named IoTSys to ease the integration of legacy protocol-driven devices into IPv6 for capillary integration.

UDG has been used by the IoT6 project to integrate heterogeneous IoT devices into the IoT6 architecture, enabling efficient and large scale integration of heterogeneous pilot deployments, including several smart buildings and the smart city of Santander. The benefit of an all-IPv6 integration simplified the deployment and management of these distributed networks of heterogeneous IoT.

Identifier integration

The project participants realized that the identification mechanism could be extended in a very powerful way by treating each end device as a digital object, with its own (one or more) Identifiers. Each Identifier can be associated with its own attributes and there may be several different attributes for the same device used by different application providers.

Access to both the identifiers and to their attributes can require authorization via strong authentication. In our IoT6 project we showed how IPv6 could be combined with identification solutions such as Handle Digital Object Identification – DOI (http://handle.net/). It could be used to assist security, by storing security and authentication tokens in the attribute store of the information system. The potentially complex project of restricting access to end-devices to authorized processes can then be resolved in a proxy manner, removing the need to put too much complexity in the end-devices. The handle records could be used to provide role-based descriptions of a device, since the end-devices (smart objects) could be provided with several application-specific identities (including IPv6 address). Because processes and devices have similar identifier characteristics, the attributes can include the identifier prescribing the access process for a device. Some of these advantages were demonstrated in the implementation by using the Handle existing Identifier-resolution system.

Use cases

IoT6 has been tested in different use-cases such as building automation and smart office. Its versatility has allowed integrating heterogeneous technologies for automation in building and homes such as BACnet, Z-Wave, ZigBee, Bluetooth, X10, Konnex, at the same time that has integrated other technologies such as Kinnect, Google Glass, and personal devices. Finally, a vertical integration with backend systems for business process development and events analysis has been also demonstrated. Therefore, the use-cases have demonstrated the versatility in terms of physical and cybernetic platforms that can be integrated with the developed SOA in IoT6.

Lessons learned

After three years of intensive research on IPv6 and IoT, our IoT6 project reached several conclusions.

• IPv6 is a strategic enabler for IoT scalability, manageability and interoperability. We draw this conclusion from the fact that IPv6 is a well-tested technology, developed from the lessons learned from 30 years' experience with a continuously growing internet that has been based on IPv4.
• IPv6 is a convenient multi-systems and cross-domain integrator. This conclusion is based on the fact that IPv6 abstracts from the physical and medium layer into a common, homogenous networking layer. This makes IPv6 cross-domain and global, a quality that is not undermined by the multiple technologies being used at the medium level.
• IPv6 – IoT integration is logical and increasing. The foregoing points, in conjunction with the IPv6 adoption curve presented in our previous article, provide a logical basis for the use of IPv6 for IoT. No alternative currently provides the scalability, manageability and interoperability that IPv6 does for IoT.
• IPv6 adoption is accelerating, particularly in several Asian, European and South American countries, thus its momentum and unique qualities make it suitable as a global solution.
• For large deployments with multiple applications providers, there is currently no viable alternative to IPv6. Moreover, identifier-based systems will greatly ease operational security. This point is underscored by the emergence of Future Internet architecture, where identification and location spaces are split; IPv6 continues to be considered as the reference technology for location. To be fair, other technologies are emerging as reference technologies for identification, in order to bring additional benefits to multi-homing, mobility and security. The actual adoption of those alternative, reference technologies, however, remains limited.
• A need for global IoT standards enabling cross-domain interoperability is growing. Based on the emergence of 6LoWPAN, GLowBAL IP, Bluetooth Smart 4.2 with Internet Protocol support, ZigBee IP, etc., global IoT standards are likely to be IPv6-based. Also, the World Wide Web is based on an IP protocol, which suggests the solution for IoT will also be IP-based. IPv6 is the logical extension of the IP protocols that enable the current WWW.

Conclusion

IPv6 meets several fundamental criteria for driving IoT development. It has an open and scalable architecture. It exists today and is being adopted for mobile networks and applications at an accelerating rate. It provides the means to deploy both centralized networks (intranets) and distributed networks (internet). It can handle all types of traffic. It interoperates with most if not all available industry standard network links. Open standardization processes exist at established standards bodies.

IPv6 still needs research and development efforts on security and privacy. Work is needed for IPv6 to overcome address translation limitations. A transition model for moving from IPv4 to IPv6 remains to be worked out. Once these hurdles are addressed, IPv6 will need to be adopted by governments to provide leadership and economies of scale to spur greater adoption. IPv6 is not the perfect solution, but it represents the "art of the possible" for IoT.

 

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Sébastien Ziegler is the founder and Director of Mandat International, a foundation based in Geneva with special consultative status to the UN and a member of the International Telecommunication Union. He graduated in international relations at the Graduate Institute of International Studies in Geneva, followed by a Master in Environment, an MBA in international administration (HEC Geneva), and complementary executive courses at Harvard Business School, Stanford University, UC Berkeley and EPFL. Sébastien founded two foundations, as well as two ICT-related SMEs and several organizations, including ICT-related alliances. He is Vice President of the IoT Forum and Vice Chair of the IEEE ComSoc Subcommittee on the IoT. He initiated several national and international research projects in the area of ICT, with a focus on Internet of Things, IPv6, multiprotocol interoperability and crowdsourcing. He initiated and coordinates several European research projects on IoT, including IoT6 (www.iot6.eu), IoT Lab (www.iotlab.eu) on IoT and crowdsourcing, and Privacy Flag on privacy and personal data protection.

 

Peter Kirstein is Professor of Computer Communications Systems at University College London. He is a fellow of many professional bodies including the Royal Academy of Engineering, American Academy of Arts and Science, US National Academy of Engineering. He has received many awards including the Commander of the British Empire, SIGCOMM, Postel, Lifetime achievement of Royal Academy of Engineering and Marconi.
Peter has led many projects in computer networks, communications and applications – both National and EC – included IPv6 activities in public safety, videoconferencing, security and sensor networking. He led the Networking Work-packages in both U2010 and IoT6.

 

Latif Ladid holds the following positions: Founder & President, IPv6 FORUM; Founder & Chair, 5G World Alliance; Chair, ETSI IP6 ISG; Chair, IEEE ComSoc 5G MWI & IoT subTC; Emeritus Trustee, Internet Society; Board Member IPv6 Ready & Enabled Logos Program. He is a Research Fellow at the University of Luxembourg on multiple European Commission Next Generation Technologies IST Projects. He is also Board Member of 3GPP PCG (www.3gpp.org), member of UN Strategy Council, and member of the Future Internet Forum EU Member States (representing Luxembourg).

 

Antonio F. Skarmeta received the M.S. degree in Computer Science from the University of Granada and B.S. (Hons.) and Ph.D. degrees in Computer Science from the University of Murcia, Spain. Since 2009 he is a Full Professor at the Computer Science department of the University of Murcia. Antonio Skarmeta has worked on different research projects in the national and international area in the networking, security and IoT areas, such as Seinit, Deserec, Enable, Daidalos, SWIFT, IoT6, SMARTIE and SocIOtal. He has published over 90 international papers and is a member of several program committees. He has also participated in several standardization activities being co-author of some drafts at the IETF.

 

Antonio Jara has received two Master Sciences (Hons. – valedictorian) degrees: a Master in Business Administration – MBA (Hons), and PhD (Cum Laude). He is especially focused on the design and development of new protocols for security and mobility for the Internet of things, the topic of his Ph.D. He is currently working on IPv6 technologies for the Internet of Things in projects such as IoT6, and also Big Data and Knowledge Engineering for Smart Cities in collaboration with projects such as SmartSantander.
Antonio has published over 80 international papers about the Internet of Things and holds one patent in the Internet of Things area. His specialties are: Internet of Things, IPv6, Future Internet, e-health, AAL, healthcare, 6LoWPAN, RFID, Bluetooth Low Energy, IoT6, and security. Antonio is interested in developing new proposals for H2020 in the areas of IoT, Big Data, mHealth, IPv6, SDN and User Experiences.