Zigbee bluetooth wifi wimax

Wifi, Wimax, IR, NFC, Bluetooth, ZigBee – What they do in IOT?

The Internet Of Things (IOT) is a fantasy world full of jargons and buzz words. But in reality, it is much simple if we understand the basic concepts well. I request you to read through my earlier articles to understand the basics of IOT, building blocks of IOT, IOT architecture and protocols in IOT.

In the previous article, we looked at the different protocols that are used in IOT layer wise.If I may draw your attention to the link layer, you may see some protocols stacked up there. What are they used for? Which one to choose? Let us explore these in detail through this article.

We all know that the amount of information available to use these days is mainly due to the connectivity of devices, including computers, mobile phones, servers etc. The level to which these connections are exposed determine the open availability of data. For example, in a closed network, the data might be available only within that particular network range whereas in the case of internet, it is available everywhere.

You get the point? Let me illustrate you with an analogy. In your home, if you want to connect your laptop with a PC and mobile phone, you will establish your Personal Area Network. If you are in an office or school intranet, you can connect with any of the devices within that network (LAN) to send and receive data. But, somebody outside of this network would be completely isolated, right? Now, assume that you have your office in 10 locations across the world. You might consider changing your LAN to a WAN (Wide Area Network) to provide extended access.

When you build this outward, you venture into a wider network connecting a wider audience ultimately connecting various devices incrementally thereby offering more data. Well, if you have understood so far, let us get into our topic for today.

Wifi, Wimax, IR, NFC, Bluetooth and ZigBee are short range communication wireless protocols that you can use to construct your networks. Though, all of these are used for a similar cause, they differ with their operational nature.

Let’s take the case of Wifi. It is used for connecting our personal devices through a router.This can be used for high amount of data transfer, but it is a bit power consuming and thus works out costlier. There is also a range limit, may be 300 feet depending on the router that you use.

Wimax is very similar to Wifi but it is much faster and thus even costlier. Wimax can have a range of upto 30 miles.

IR and NFC are line of sight protocols as the devices that need to communicate through IR and NFC need to see each other. Your television remote or AC remote need to be held straight in front of the device to make it work. Similarly, if two mobile phones need to communicate through NFC, they need to be brought together. Here, the amount of data transferred is very less.

Bluetooth is better than IR and NFC as it allows a much wider range up to 10m and you don’t need to have the devices face each other. You can mostly transfer files through Bluetooth. The hands free set for your mobile, wireless mouse, keyboard etc can make use of Bluetooth.

Zigbee is not as prominent with the layman as it is with the technicians. Infact, most of the devices that we use today have Zigbee inside them. Zigbee is nothing but a protocol that operates through a modem and a module. There are various types of Zigbee modules for various use cases.

Zigbee is also a short range protocol that works upto 50 meters. It utilizes low power but transfers data slowly (low bandwidth). Why you need to use Zigbee then? Because it brings on lot of savings in the form of battery life and cost. When you want billions of devices to communicate together, cost is a very essential factor.

Practically, there are many vendors who manufacture Zigbee compliant modules(Xbee being one of them). These modules can be plugged into a microcontroller board like Arduino that has a USB port to connect with your computer. It also has a driver program for installation. Once installed, you can do various programming through specific languages.

To give you an idea of how they look like, I request you to take a look at the below images

Arduino board with Xbee module plugged in.

That’s it for today. Hope you understood the use of various protocols in the link layer and specifically Zigbee. It is very important to understand these as IOT will make heavy use of these technologies. Thanks for reading and hope to meet you with the next article.

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Беспроводные сети передачи данных

Bluetooth
До 1 мбит/с – базовый стандарт 1.0
2-3 мбит/с – Bluetooth 2.0 + EDR
Zigbee
20 кбит/с – для диапазона 868-868,6 (BPSK)
40 кбит/с – для диапазона 902-928 (BPSK)
250 кбит/с – для 2400-2483,5 (QPSK)

13. Пропускная способность канала

WiFi
Стандарт
Пропускная способность
IEEE 802.11
1 и 2 Мбит/с
IEEE 802.11b
11 и 5,5 Мбит/с
IEEE 802.11a
6,9…54 Мбит/с
IEEE 802.11g
До 54 Мбит/с
IEEE 802.11n
До 600 Мбит/с (с исп. MIMO)
IEEE 802.11ac
Свыше 6 Гбит/с (с исп. MU-MIMO)
WiMax
До 75 Мбит/с – Mobile Wimax
120+Мбит/с – Fixed WiMax

14. Методы доступа к среде передачи данных

Bluetooth
CDMA , TDMA (внутри одной пикосети)
FDMA (между разными пикосетями)
ZigBee
CSMA/CA
WiFi
CSMA/CA
WiMax
OFDMA

15. Технология расширенного спектра

Используется для увеличения
помехоустойчивости и зашиты данных
Типы расширения:
1) Расширение спектра скачкообразной
перестройкой частоты (FHSS) – Bluetooth, WiFi
2) Прямое последовательное расширение спектра
(DSSS) – Zigbee, WiFi

16. Метод расширения спектра

17. Метод расширения спектра

18. Кодирование и защита от ошибок

Коды обнаружения ошибок
Коды с коррекцией ошибок (FEC)
Протоколы с автоматическим
запросом повторной передачи (ARQ)

19. Архитектура Bluetooth

20. Архитектура Zigbee

21. Архитектура WiFi

22. Архитектура WiMax

23. Стек протоколов Bluetooth

24. Стек протоколов ZigBee

25. Режимы AdHoc, Mesh

26. Инфраструктурный режим

27. Режим клиента

28. Режим базовой станции

29. Организация и планирование сети WiFi

30. Организация и планирование сети WiMax

31. Угрозы и риски безопасности беспроводной сети

32. Механизмы обеспечения безопасности в сети

33. Вопросы

1) Какие технологии расширения
спектра существуют?
2) Какие существуют угрозы и риски
безопасности беспроводных сетей?
3)Основные элементы сети ZiBee и их
функции?

34. Список источников

Широкополосные беспроводные сети передачи
информации, В.М.Вишневский
Энциклопедия WiMax путь 4G, В.М.Вишневский
Современные технологии беспроводной связи,
И.Шахнович
rtls.net
lastmile.su

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Zigbee bluetooth wifi wimax

Various types of wireless technology and networks allow devices to speak (send data) to each other and to the web (TCP/IP Networks) without cables. There are a number of different wireless technologies out there that can be implemented in hardware products for the Internet of Things (IoT) and Machine to Machine (M2M) communication. The Institute of Electrical and Electronics Engineers (IEEE) has seven task groups in place for 802.15 technologies. Those groups set the standards for common types of wireless technologies used for personal area networks. Those 802.15 task groups include: WPAN/Bluetooth, Coexistence, High Rate WPAN, Low Rate WPAN, mesh Networking, Body Area Networks, and Visible Light Communication. Each IEEE protocol has its own distinct advantages and limitations. Promising developments expand their potential applications and uses.

IEEE 802.15.4: What is ZigBee?

A wireless technology currently gaining traction is the LPWAN group, ZigBee, an open global standard and is designed specifically to be used in M2M networks. The technology is inexpensive to run and doesn’t require a lot of power, making it an ideal solution for many industrial applications. The technology has a low latency, and a low duty cycle, allowing products to maximize battery life. The ZigBee protocol offers 128-bit AES encryption. The technology is also used in Mesh networks, which allow nodes to be connected together through multiple pathways. The wireless technology is hoped to ultimately be implemented in things like smart home devices. The technology’s ability to connect multiple devices together simultaneously makes it ideal for a connected home environment where users may want things like smart locks, lights, robots, and thermostats to talk to one another. The ZigBee Alliance recently standardized the technology, hoping to make that connectivity possible. Currently all ZigBee devices aren’t capable of talking to all other ZigBee devices. The hope is that standardization will correct that issue and that the devices will offer a uniform experience for the end user. At Link Labs, many of our customers are former ZigBee users, but we found that range and performance limited their applications.

IEEE 802.11: WiFi

WiFi uses radio waves (RF) to allow two devices to communicate with one another. The technology is most commonly used to connect Internet routers to devices like computers, tablets and phones; however, it can be used to connect together any two hardware components. WiFi is a local wireless network that runs of the 802.11 standards set forth by the Institute of Electrical and Electronics Engineers (IEEE). WiFi can utilize both the global 2.4GHz UHF and 5GHz SHF ISM radio bands. The WiFi Alliance certifies some products, allowing them to be labeled as “Wi-Fi Certified.” In order to receive that designation, and product must go through the Alliance’s interoperability certification testing. 802.11b, 802.11g, and 802.11n run on the 2.4GHz ISM band. The band is susceptible to interference from some Bluetooth devices as well as some microwave ovens and cordless phones. Devices that run on either band can be operated in the United States without a license from the FCC, but still require FCC part 15 certification. The first six channels of frequencies from each are considered part of the amateur radio band. For further reading, here are 8 things you didn’t know about WiFI and and examination of the future of WiFi.

IEEE 802.15.1: Bluetooth and BLE

Bluetooth and Bluetooth Low Energy (BLE) (what’s the difference?) are wireless technologies used to transfer data over short distances. The technology is frequently used in small consider devices that connect to users phones and tablets. For instance, the technology is used in many speaker systems. Bluetooth Low Energy uses less power than standard Bluetooth and is used in hardware such as fitness trackers, smart watches, and other connected devices in order to wirelessly transmit data without heavily compromising the battery power in a user’s phone. BLE has only recently started to pick up steam. The technology was initially introduced by smartphone maker Nokia in 2006, but didn’t become part of Bluetooth standard until 2010. Today, BLE, which is also referred to as Bluetooth Smart, is supported by the majority of smartphone and computer makers as well as most major operating systems including Windows 8, OS X, Linux, Windows Phone, Android and iOS. Bluetooth uses UHF radio waves for data transfer. The technology was originally standardized as IEEE 802.15.1, but the IEEE no longer maintains that specific standard. Companies that work with Bluetooth are often affiliated with the Bluetooth Special Interest group (SIG). The group currently has over 20,000 members, and must certify a product before it can be marketed as a Bluetooth device to the consumer or business market. That certification helps ensure that all Bluetooth devices work in a standardized way and provide a similar experience for consumers. For further reading, here’s 6 things you didn’t know about Bluetooth.

IEEE 802.16: WiMax

WiMax stands for Worldwide Interoperability for Microwave Access. This wireless technology allows data to be transferred at a rate of 30–40 megabits per second. The term refers specifically to interoperable implementations of the IEEE 802.16 wireless family. The technology was once used by several mobile carriers, notably Sprint, to deliver wireless data to its customers. Sprint, along with many of the other carriers who used the technology, have since switched over to using faster LTE 4G networks for data. The WiMax Forum certifies devices before they can be sold to consumer or businesses. The technology can be used both indoors and outdoors, however, WiMax devices typically produce a better signal when used outside or by a window.

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