A deep dive into Internet of Things Standards
Internet of Things (IOT) is an ambitious paradigm which would revolutionize how we look at device connectivity and interoperability , as well as exponentially increase the scale of connected devices .In order to manage complexity of such a scale , we require internetworking solutions , which can use and re-use the pre-existing technologies seamlessly with newer and more efficient technologies .
Why Standardization?
Standards implies Internetworking of equipments from multiple vendors and interoperability of myriad of solutions which ride of the top the vendor specific equipments. The potential benefits could include
- Reduction in Development Cost
- Reduction in Deployment Cost
- Market Expansion and Faster Go To Market.
Standardization is a key enabler to remove the technical barriers and ensure interoperable M2M services and networks
Two of the predominant challenges that IOT Implementation would face includes:-
- Presence of Low Powered devices
- Continuous and frequent data exchanges over a Lousy network
These unique challenges, marks a question mark on the use of the existing internet protocols. As we progressed from the HTTP, TCP , IP Stack to the IOT specific protocol stack , we encountered or are confronted with a myriad of wireless protocols like Zigbee , RFID , Bluetooth to next generation protocol standards such as 6LoWPAN , CoAP , 802.15.4e etc. which works towards a common goal of unifying all the wireless sensor networks and marriage it with the established internet .
IOT Protocol Stack
The internet Protocol is the way forward for even the smallest of devices. IPv6 have succeeded IPv4 , allowing for approximately 3.4 x 1038 unique addresses. A new protocol 6LoWPAN was defined to enable IPv6 packets to be carried on top of low-powered and lousy personal area networks (LLNs).
The underlying physical and MAC layer for the 6LoWPAN protocol is the IEEE 802.15.4 standard
The application layer protocol for introducing the Web-services paradigm in the “Internet of Things” incorporates a REST based web transfer protocol called Constrained Application Protocol (CoAP). This protocol includes several HTTP functionalities but has been re-designed to take into account the low processing power and energy consumption constraints of IOT devices
Other IOT Alliances and Protocols
There are various Alliances and discussions on the development and implementations of protocols to realize the goal of Interoperability. Some of the protocols which are relevant from an IOT solution perspective are
- Message Queue Telemetry Transport (MQTT) – Developed by IBM , is a lightweight publish/subscribe messaging transport connectivity protocol
- ZigBee Alliance – ZigBee (XBee) is a set of application profiles for creating low-rate wireless mesh networks which has been built upon the 802.15.4-2003 standard.
- DASH 7 Alliance – Dash7 works at the 433 MHz frequency and typically has a range up to 1 KM
- BACnet – This is a communications protocol for Building, Automation and Control networks. It is essentially used in HVAC systems
MQTT vs CoAP – Application Layer Interoperability
MQTT protocol is ideally suited for resource constrained environments, with attributes like
- Expensive network with low bandwidth and unreliable
- Runs on embedded devices with limited processor or memory resources.
MQTT is an open publish/subscribe protocol designed for asynchronous transfer of telemetry messages
CoAP is being standardized for Low-powered and Lousy networks. Unlike MQTT, it is conceptually separated into two sub layers viz., messaging layer and a request-response sub layer responsible for handling the messaging services and requests response respectively.
On the outset, resonating from the limitless possibilities and complexities of IOT, there might be a situation, where an application running on a low powered device uses the MQTT Protocol and may need to communicate with a remote device which understands CoAP based messages.
A probable solution in the IOT world would be to simple enable the client and server to handle both the MQTT and CoAP protocols, depending on the capabilities of remote device. But , in an ecosystem where the processing and memory availability is highly constrained , implementing multiple protocols on these low powered devices won’t be a feasible solution , which calls for the need of IOT Gateways or middlewares which can provide protocol level interoperability, by translating the data, context or the meaning of the message from one protocol to another protocol.
IOT Standardization Timeline
