UNIT 4
Wireless Technologies for IoT: Layer ½ Connectivity
Machine-to-machine (M2M)
Machine-to-machine, or M2M, is a broad label that can be used to describe any technology that enables networked devices to exchange information and perform actions without the manual assistance of humans. Artificial intelligence (AI) and machine learning (ML) facilitate the communication between systems, allowing them to make their own autonomous choices.
M2M technology was first adopted in manufacturing and industrial settings, where other technologies, such as SCADA and remote monitoring, helped remotely manage and control data from equipment. M2M has since found applications in other sectors, such as healthcare, business and insurance. M2M is also the foundation for the internet of things (IoT).
M2M applications and examples:
Machine-to-machine communication is often used for remote monitoring. In product restocking, for example, a vending machine can message the distributor's network, or machine, when a particular item is running low to send a refill. An enabler of asset tracking and monitoring, M2M is vital in warehouse management systems (WMS) and supply chain management (SCM).
Utilities companies often rely on M2M devices and applications to not only harvest energy, such as oil and gas, but also to bill customers -- through the use of smart meters -- and to detect worksite factors, such as pressure, temperature and equipment status.
M2M apps
In telemedicine, M2M devices can enable the real time monitoring of patients' vital statistics, dispensing medicine when required or tracking healthcare assets.
IoT and M2M:
The combination of the IoT, AI and ML is transforming and improving mobile payment processes and creating new opportunities for different purchasing behaviours. Digital wallets, such as Google Wallet and Apple Pay, will most likely contribute to the widespread adoption of M2M financial activities.
Smart home systems have also incorporated M2M technology. The use of M2M in this embedded system enables home appliances and other technologies to have real time control of operations as well as the ability to remotely communicate.
M2M is also an important aspect of remote-control software, robotics, traffic control, security, logistics and fleet management and automotive.
Key features of M2M technology include:
- Low power consumption, in an effort to improve the system's ability to effectively service M2M applications.
- A Network operator that provides packet-switched service
- Monitoring abilities that provide functionality to detect events.
- Time tolerance, meaning data transfers can be delayed.
- Time control, meaning data can only be sent or received at specific predetermined periods.
- Location specific triggers that alert or wake up devices when they enter particular areas.
- The ability to continually send and receive small amounts of data.
Zigbee /IEEE 802.15.4
ZigBee is similar to Bluetooth and is majorly used in industrial settings. It has some significant advantages in complex systems offering low-power operation, high security, robustness and high and is well positioned to take advantage of wireless control and sensor networks in IoT applications. The latest version of ZigBee is the recently launched 3.0, which is essentially the unification of the various ZigBee wireless standards into a single standard.
Z-Wave
Z-Wave is a low-power RF communications IoT technology that primarily design for home automation for products such as lamp controllers and sensors among many other devices. A Z-Wave uses a simpler protocol than some others, which can enable faster and simpler development, but the only maker of chips is Sigma Designs compared to multiple sources for other wireless technologies such as ZigBee and others.
ZigBee and 802.15.4
ZigBee targets radio frequency applications that require a low data rate, long battery life, proximity and secure networking. One advantage of the ZigBee protocol is the ability to minimize the time the radio is on and to reduce power consumption. Commercial Zigbee devices operate in the industrial, scientific and medical (ISM) radio bands at 2.4 GHz. A significant disadvantage for ZigBee in WBAN applications is due to the interference with WLAN transmission that uses the same frequency bands.
Radio Frequency for consumer
A radio wave is an electromagnetic frequency used for long distance communication. IoT solutions rely on IoT wireless technology, leveraging radio waves that follow a specific protocol based on the design intent of the IoT system. Radio protocols are used by IoT devices to transport data to cloud platforms where a physical or wired connection does not exist. There are many different protocols to choose with characteristics varying in areas of power consumption, physical size, travel distance, data size, and transport technology availability.
Radio frequency bands are, quite simply, any of the electromagnetic wave frequencies that are used in radio communication. They range from 3khz to 300Ghz and encompass everything from amateur radio bands to mobile phones and beyond. There are multiple types of bands as well:
- Unlicensed Bands have become popular for many commercial solutions (Bluetooth, WiFi, etc)
- Licensed bands require a license from a local regulatory authority, and are used primarily by TV and cellular networks
- Forbidden Bands are used by government agencies and public service organizations
Radio frequencies are versatile, but like any job, it’s up to you to choose the right tool that suits your IoT wireless technology needs. Does your device frequently transfer massive amounts of data? You’ll want a high-bandwidth solution. Does your device need to transmit data over a long distance? A lower frequency will do the job. There are many factors to consider when choosing a radio solution, but there are also many choices available for whatever your needs may be.
Long-Range (LoRa)
LoRa (short for Long Range) continues to gain attention in the marketplace. It offers a compelling mix of long range, low power consumption, deep indoor coverage, and secure data transmission. LoRa operates in the unlicensed <1GHz frequency range. It uses spread spectrum technology so that adjacent transmitters are less likely to interfere with each other. This increases the capacity of each gateway. Spread spectrum communications also provide a “coding gain” over narrow band communications. This results in a stronger communications link, which can support longer range communications. LoRa data rates range from 0.3 kbps to 50 kbps and can support a range of up to 15km.
Sigfox
Sigfox uses low data rate transmission and sophisticated signal processing to effectively avoid network interference, and ensures the integrity of the transmitted data. This IoT wireless technology solution allows bidirectional communication, but always initiated by the device. As such, Sigfox is effective for communications from endpoints to base stations (uploads). However, it is not effective for communications from base stations to endpoints (downloads). Sigfox consumes a fraction (1%) of the power used through cellular communication. This network solution would be ideal for one-way systems including basic alarm systems, simple metering, and agricultural and environmental sensors.
4.1.1 Electronics ( RF4CE), Bluetooth and its low-energy profile , IEEE 802.15.6 WBANS, IEEE
Electronics (RF4CE)
The RF4CE remote control isn’t the typical infrared device found in the home. Instead, it’s an RF-based product designed to conform to ZigBee specifications as part of a wireless network. The ZigBee wireless network managing the RF4CE device is designated to be active on three ZigBee predefined channels—15, 20, and 25—from the ZigBee extending from channel 11 to channel 26.
Most people have used some form of Wi-Fi, often in their home networks. Those familiar with Wi-Fi operation shouldn’t be confused between the channels designated to Wi-Fi and those designated to ZigBee in the 2.4-GHz band.
ZigBee devices that operate with RF4CE remote controls include TV sets, DVD players, and set-top boxes, plus others that may be added in the near future. In the RF4CE world, the remote control is the focal device. Others, such as the DVD player, are “targets.”
IEEE 802.15.6 WBANS
Wireless Body Area Networks (WBANs) is new in the medical field, and it has the potential to grow into something very beneficial—ubiquitous healthcare monitoring. Typical examples include the early detection, prevention, monitoring of diseases, elderly assistance at home, and rehabilitation after surgery. Similarly, biofeedback applications which control emotional states and assisted living applications which improve the quality of life for people with disabilities, are getting increasing demands.
WBAN involves sensors that gather and supply physiological data to provide real-time feedback through secure data transmission with very low power consumption. This article discusses several wireless technologies and protocols used for WBAN and the potential challenges to implementation in the medical space.
WBANs use the follow different short-range radio technologies.
IEEE 802.15.6
The IEEE 802.15.6 standard is the latest international standard for WBAN. It uses different frequency bands for data transmission, including the narrowband (NB), the ultra-wideband (UWB), and the human body communication (HBC). The IEEE 802.15.6 is specifically designed to support a wide range of data rates, to consume less energy, and is exceptionally reliable within the surrounding area of the human body.
IEEE 802.11
The oldest wireless technology used in medical applications is the IEEE 802.11, which is a set of standards for a wireless local area network (WLAN). With high-speed wireless connectivity, it allows large data transfers for video calls and video streaming. The advantage of WLAN is all smartphones, tablets and laptops have Wi-Fi integration. However, the high consumption of energy is a drawback.
Bluetooth and Bluetooth Low Energy (BLE)
Bluetooth and Bluetooth Low Energy (BLE) is a short-range communication protocol. BLE is a derived option of Bluetooth that is more suitable for WBAN applications because of its extremely low power idle mode, uncomplicated device discovery and reliable data transfer. BLE uses few channels for pairing devices which makes it ideal for latency-critical applications; one example is an emergency alarm generation in healthcare facilities. However, just like ZigBee, Bluetooth and BLE operate in the 2.4 GHz ISM band, making it susceptible to interference with other devices that use the same frequency bands.
The ability to track physiological signals of patients in a real-time manner enables doctors to monitor patients’ health and to take timely actions. Examples are an electrocardiogram (ECG), heart rate, blood pressure, oxygen saturation, body temperature, and body weight. However, they are not without challenges.
4.1.2 802.15WPAN TG4j, MBANS, NFC, dedicated short range communication (DSRC) & related
The purpose of TG4j is to create an amendment to 802.15.4 which defines a physical layer for IEEE 802.15.4 in the 2360 to 2400 MHz band and complies with Federal Communications Commission (FCC) MBAN rules. This amendment may also define modifications to the MAC needed to support this new physical layer.
The FCC has issued a Notice of Proposed Rule Making (NPRM) (FCC NPRM 09-57) to allocate the band 2360 to 2400 MHz for MBANSs using body sensor devices. – Service and technical rules allow such devices to operate in this band either on a licensed-by-rule basis under the Medical Device Radiocommunication Service (MedRadio Service) or on a licensed and nonexclusive along with a frequency coordination model to minimize interference to incumbent users in the band. • This project defines an alternate PHY and the necessary modifications to the MAC that are needed to support the PHY operation according to the FCC rules in the MBAN band.
IEEE 802.15.6 is addressing communication in the vicinity of, or inside, a human body.
• The proposed amendment to IEEE 802.15.4 will address low data rate applications.
• IEEE P802.15.6 is targeting significant high data rates and lower power consumption applications
NFC
Contactless communication allows a user to wave the smartphone over an NFC-compatible device to send information without needing to touch the devices together or go through multiple steps setting up a connection.
• NFC is an offshoot of radio frequency identification (RFID), with the exception that NFC is designed for use by devices within close proximity to each other.
• NFC utilizes electromagnetic radio fields while technologies such as Bluetooth and Wi-Fi rely on radio transmissions.
• The technology behind NFC allows a device, known as a reader, interrogator, or active device, to create an electromagnetic field that interacts with another NFC compatible device or a small NFC tag holding the information the reader requires.
• Passive devices, such as the NFC tag in smart posters, store information, and communicate with the reader, but these devices do not actively read other devices.
• Three forms of NFC technology exist— Type A, Type B, and FeliCa; all three types are similar, but communicate in slightly different ways.
• NFC maintains interoperability between different wireless communication methods such as Bluetooth and other NFC standards
WPAN Technologies for IoT/M2M NFC
Standards exist to ensure all forms of NFC technology can interact with other NFC-compatible devices and will work with newer devices in the future.
Two major specifications exist for NFC technology:
- ISO/IEC 14443 and ISO/IEC 18000-3. – The ISO/IEC 14443 defines the ID cards used to store information, such as that found in NFC tags. The latter specifies the RFID communication used by NFC devices. – ISO/IEC 18000-3 is an international standard for all devices communicating wirelessly at the 13.56 MHz frequency using Type A or Type B cards, as is the case for NFC.
- The devices must be within 4 cm of each other before they can transfer information.
- NFC tag is simply referred to as the tag.
Dedicated short range communication (DSRC) & related
Dedicated short-range communication (DSRC) is a wireless communication technology designed to allow automobiles in the intelligent transportation system (ITS) to communicate with other automobiles or infrastructure technology. DSRC technology operates on the 5.9 GHz band of the radio frequency spectrum and is effective over short to medium distances.
DSRC has low latency and high reliability, is secure, and supports interoperability. It receives very little interference, even in extreme weather conditions, because of the short range that it spans. This makes it ideal for communication to and from fast-moving vehicles. DSRC technology can be used in either a vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) format, and communicates using transponders known as on-board units (OBUs) or roadside units (RSUs). In V2V, DSRC is used to allow vehicles to communicate with each other through OBUs. This communication is usually for safety reasons, such as to alert the driver of one car that the car in front of it is about to slow down. In V2I, an OBU in or on the vehicle communicates with surrounding infrastructure equipped with an RSU. This can also alert the driver to safety risks, such as that they are approaching a curve too quickly, or can be used to collect tolls and parking payments. In 1999, the United States Federal Communications Commission (FCC) allocated the 5,725 MHz to 5,875 MHz band of radio frequency for DSRC communication. The ITS Joint Program Office of the US Department of Transportation conducts research on DSRC and other wireless communication technologies and their uses in vehicle safety.
4.1.3 Comparison of WPAN technologies cellular & mobile network technologies for Protocols.
Wireless IoT Network Protocols
Below, we’ve compiled an extensive—but not exhaustive—list of Internet of Things (IoT) protocols, in no particular order. If you’re looking for an IoT network protocols comparison, this is great place to start.
But first, a word of caution: Don’t worry so much about the protocol until you know precisely what your application needs. Deciding you need interoperability or a protocol led by a big-name industry player before understanding what kind of technology is right for your application simply won’t do. Our advice? Get to know these IoT network protocols, but don’t get your mind set on any of them until you know what you need to accomplish.
Bluetooth
Bluetooth is a global 2.4 GHz personal area network for short-range wireless communication. Device-to-device file transfers, wireless speakers, and wireless headsets are often enabled with Bluetooth.
BLE
BLE is a version of Bluetooth designed for lower-powered devices that use less data. To conserve power, BLE remains in sleep mode except when a connection is initiated. This makes it ideal for wearable fitness trackers and health monitors.
ZigBee
ZigBee is a 2.4 GHz mesh local area network (LAN) protocol. It was originally designed for building automation and control—so things like wireless thermostats and lighting systems often use ZigBee.
Z-Wave
Z-Wave is a sub-GHz mesh network protocol, and is a proprietary stack. It’s often used for security systems, home automation, and lighting controls.
6LoWPAN
6LoWPAN uses a lightweight IP-based communication to travel over lower data rate networks. It is an open IoT network protocol like ZigBee, and it is primarily used for home and building automation.
Thread
Thread is an open standard, built on IPv6 and 6LoWPAN protocols. You could think of it as Google’s version of ZigBee. You can actually use some of the same chips for Thread and ZigBee, because they’re both based on 802.15.4.
WiFi-ah (HaLow)
Designed specifically for low data rate, long-range sensors and controllers, 802.11ah is far more IoT-centric than many other WiFi counterparts.
IETF Mobile IP Protocol
When away from home, mobile host has a care-of-address – care-of-address = address of foreign agent within the foreign subnet - the foreign agent delivers forwarded packets to mobile host – care-of-address may also be a temporary IP address on the foreign network
When moving, the host registers with home agent - home agent always knows the host’s current care-of-address.
• Correspondent host = Host that wants to send packets to the mobile host
• Correspondent host sends packets to the host’s Mobile IP address, which are routed to the host’s home network
Correspondent host need not know that the destination is mobile. Home agent encapsulates and tunnels packets to the mobile host’s care-of-address.
The distinction between Machine to Machine (M2M) and the Internet of Things (IoT) can be baffling. In fact, the misconception that M2M and IoT is the same has been a continuing subject of discourse in the tech-sphere. But now, more than ever, as both technologies continue to evolve at break-neck speed. Both M2M and IoT boast of remote device access. Thus, the two terms have been interchanged mistakably often. While both are connectivity solutions for enterprise, they are each two different schools of solution. M2M and IoT connect different things but achieve connectivity differently. Before delving deeper into the discussion of differences, here is a quick run through on where both technologies overlap
IoT/M2M systems layers:
Layer 1: M2M Application Domain
• Integration, Collaboration and M2M Application Services
• Application (Reporting, Analysis, control)
Layer 2: Network Domain
• M2M server, device identity, device and device-network management, Data Analysis, Abstraction, Accumulation, and Management
• uni-cast and multicast message delivery
• Core functionalities for monitoring Connectivity (Communication and Processing Units)
Layer 3: M2M device communication domain
• M2M Devices Domain Communication
• Gateway
• Physical devices and Controllers (the things in IoT) [Sensors, machines, devices, Intelligent Edge nodes of Different Types
Key Takeaways
- Two major specifications exist for NFC technology:
- ISO/IEC 14443 and ISO/IEC 18000-3. – The ISO/IEC 14443 defines the ID cards used to store information, such as that found in NFC tags. The latter specifies the RFID communication used by NFC devices. – ISO/IEC 18000-3 is an international standard for all devices communicating wirelessly at the 13.56 MHz frequency using Type A or Type B cards, as is the case for NFC.
- The devices must be within 4 cm of each other before they can transfer information.
2. NFC tag is simply referred to as the tag.
3. NFC is an offshoot of radio frequency identification (RFID), with the exception that NFC is designed for use by devices within close proximity to each other.
4. The RF4CE remote control isn’t the typical infrared device found in the home. Instead, it’s an RF-based product designed to conform to ZigBee specifications as part of a wireless network. The ZigBee wireless network managing the RF4CE device is designated to be active on three ZigBee predefined channels—15, 20, and 25—from the ZigBee extending from channel 11 to channel 26.
References
- Bernd Scholz-Reiter, Florian Michahelles, “Architecting the Internet of Things”, ISBN 978- 3842-19156-5, Springer.
- Olivier Hersent, David Boswarthick, Omar Elloumi, “The Internet of Things” Key Applications and Protocols, ISBN 978-1-119-99435-0, Wiley Publications.
