With the changing scope of applications of internet shifting towards making physical world smarter there is no doubt that people will witness a shift in the number of connected devices soon. Within 5 years it is estimated that 50 billion devices will be online. What’s more interesting is of these devices the mostly will be conventional physical objects. PCs, laptops and smart devices which dominate the internet at present will be dwarfed by these physical objects. The prerequisites of Internet of Things are many. Still the main components can be categorized into three categories i.e. intelligence, sensing and communication.
Internet of Things is going to sustain a $14 trillion market which means scope of this tech is no very large. After understanding internet of things definition you should know about the fundamentals of IoT architecture which is important to start building applications and devices.
There is no limit to applications provided prerequisites of Internet of Things are met. Healthcare, personal security, home automation, industrial automation, traffic control and environment monitoring all can be done more efficiently using this IoT tech.
Intelligence and Sensing
Wireless networks are utmost important for the success of the IoT infrastructure. Sensors should be able to communicate without constraints of physical wiring. It makes them more independent as well as increases their domain use. Sensing of capabilities of the IoT nodes should not only be efficient but also exhibit power use efficiency. The smart connected devices will be lying down dormant for most of the period. They will activate only when there is need to read or send data or to make a decision. In simple words 90% of their time sensors will not need power for relaying data or carry out any high power-consuming function. This requires the intelligent hardware to have ultra-low energy consuming sleep mode capability. Many companies are already producing microcontrollers sporting this requirement.
Wireless connectivity with low power consumption is vital for the success of IoT.
One important factor affecting the power efficiency of IoT devices is the architecture. While 32bit cores low cost microcontrollers have the advantage of being more compatible to large number of open-source software still they have high power consumption. Atmel, Texas Instruments, Freescale, and STMicroelectronics are offering such microcontrollers that make application building very fast. However the 8-bit AVR platform from Atmel still makes it obvious that there is scope of improvement in existing architectures.
To lower the power consumption by an IoT node only hardware changes is not the way. Smart communication protocols like ZigBee help in making exchange of data between devices less power consuming.
A low power consuming IEEE 802.15.4(2003) standard based specification, ZigBee is a brain child of 16 automation companies. What makes it novel is the use of mesh networking which makes utilization of communication resources much more efficient. ZigBee based IoT nodes can connect to central controller making use of in-between nodes for propagating the data. It makes transmission and handling of data robust.
Bluetooth Low Energy (BLE)
Nokia originally introduced this protocol as Wibree in 2006. Also known as Bluetooth Smart this protocol provides the same range coverage with much reduced power consumption as the original Bluetooth. It has similar bandwidth with narrow spacing as used by ZigBee. Low power latency and lower complexity makes BLE more suitable to incorporate into low cost microcontrollers.
Low power latency and lower complexity makes BLE more suitable to incorporate into low cost microcontrollers.
As far as application is concerned BLE is in healthcare sector. As wearable health monitors are becoming prevalent the sensors of these devices can easily communicate with a smart phone or any medical instrument regularly using BLE protocol.
Counted as the most mature wireless radio technology, Wi-Fi is predominant communication technology chosen for IoT applications. Already existing protocols like WPS make the integration of internet of things devices easier with the existing network. If we talk about transmission then Wi-Fi offers the best power-per-bit efficiency. However power consumption when devices are dormant is much higher with conventional Wi-Fi designs. The solution is provided by protocols like BLE and ZigBee that reduce power consumption by sensors when devices are dormant.
The ideal solution is to mix the two technologies for optimum power utilization. GainSpan’s GS2000 is one such tech which used both ZigBee and Wi-Fi. It makes optimum use of power by putting the device into energy-saving standby mode when no data transmission is taking place. Only when device is awaked or checked for connection failure the high power consumption connection of Wi-Fi is used. BLE and Wi-Fi together can be used without interference as they are compliable to coexistence protocols. The Bluegiga APx4 is one such solution which supports both BLE and Wi-Fi and is based on 450MHz ARM9 processor.
Most important use of Wi-Fi is in the applications where IP stack compliance is needed and there is high data transmission. For instance in applications sharing audio, video or remote device controlling.
As the prerequisites of internet of things are scaling up, companies are working on more integrated solutions. But even at present there are many solutions available for anyone who is trying to build up internet of things applications around the major three IoT components. Vendors like Atmel, STMicroelectronics, Texas Instruments, CSR and Freescale are offering many integrated microcontrollers and support chipsets making application building a lot easier based on protocols like ZigBee, BLE and Wi-Fi.