Chapter 3 Implementing Wireless Network PDF
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This document provides a comprehensive introduction to wireless communications, covering its history, evolution, and different technologies. It explains fundamental concepts and technical details about the various types of wireless technologies.
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CHAPTER 3 IMPLEMENTING WIRELESS NETWORK Introduction of Wireless Communications Wireless communications have completely revolutionized the way we LIVE this world today. Almost everything we do, from using our ever- present smartphones to make voice calls, access information, keep up with...
CHAPTER 3 IMPLEMENTING WIRELESS NETWORK Introduction of Wireless Communications Wireless communications have completely revolutionized the way we LIVE this world today. Almost everything we do, from using our ever- present smartphones to make voice calls, access information, keep up with friends and family, watch videos and play games, listen to music, buy movie and event tickets, and thousands of other applications. Wireless is the medium of connectivity. Introduction of Wireless Communications What is wireless communication? It is the process of transmission of data from the sender to the receiver without the need for any sort of physical medium or connections, such as wires and cables, for propagation. Transmitting voice and data using electromagnetic waves in open space. Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. Introduction of Wireless Communications Why wireless communication? Reasons why we implement wireless communications. Flexibility and Modularity Cost-effectiveness Convenience Speed Constant Accessibility Introduction of Wireless Communications The history of Wireless Communications started with the understanding or magnetic and electric properties observed during the early days by the Chinese, Greek and Roman cultures and experiments carried out in the 17th and 18th centuries. Introduction of Wireless Communications Introduction of Wireless Communications Introduction of Wireless Communications In 1873, Maxwell proposed the idea of using electromagnetic waves to propagate the transmission of message signals, which is the underlying concept behind wireless communication. Guglielmo Marconi invented the first wireless device, the wireless Telegraph, in 1896 and was awarded the patent for his radio the same year. The very next year, the first wireless message was sent, which read “Are you ready?”, across a distance of 6km. James Clerk Maxwell Guglielmo Marconi Introduction of Wireless Communications Soon, advancements in radio broadcasting took place and in 1933, the first FM radio station was built in the United States. In 1946, the first commercial telephone service was set up by AT&T and Southern Bell in Saint Louis, Missouri, USA, and the service was made available to private customers as well. Introduction of Wireless Communications In 1947, a tiny device that revolutionized the computing industry was invented. The transistor, which replaced the much bigger vacuum tubes, made possible the marriage of computers and communications and also brought compactness into the picture. In 1954, the first among a line of transistor radios were built, which could fit in one’s pocket comfortably. Introduction of Wireless Communications During the 1970s and 1980s, various companies such as Bell industries and Motorola came up with their idea of a commercial cellular phone for the masses, available for the public, which also initiated the first generation(1G) of mobile telephony. In the 1990s, GSM came into the picture, connecting many more people, and brought about the second generation of mobile telephony(2G). Introduction of Wireless Communications Wireless Fidelity(WiFi) came into existence in the late 1990s. Soon after, in the year 2000, Bluetooth was invented along with the release of the third-generation (3G) of mobile telephony. These two technologies revolutionized the way people shared messages, bringing more into the wireless world. Introduction of Wireless Communications In 2007, Apple released its first iPhone (the first “actual smartphone”), which lead to an exponential increase in the number of smartphones in the market. In 2010, the fourth generation(4G) of mobile telephony rolled out, which provide facilities such as Voice over LTE. Frequencies for Radio Communication Frequencies for Radio Communication Frequencies for Radio Communication Different Wireless Technology and Usage Wireless Access Points Wi-Fi (Wireless LAN) Wi-Fi is a wireless networking technology that allows devices such as computers (laptops and desktops), mobile devices (smart phones and wearables), and other equipment (printers and video cameras) to interface with the Internet. It allows these devices--and many more--to exchange information with one another, creating a network. WiFi frequency bands are frequency ranges within the wireless spectrum that are designated to carry Wireless Routers WiFi: 2.4 GHz and 5 GHz. Mobile Hotspot Different Wireless Technology and Usage WIFI Standard Types Speed and Capability The first standard, providing a data rate up to 2 Mbps in the 2.4GHz frequency. It provided a range of a whopping 66 feet of indoors (330 802.11-1997 feet outdoors), so if you owned one of these routers, you probably only used it in a single room. The first “letter” following the June 1997 approval of the 802.11 WIFI standard, this one provided for operation in the 5GHz frequency, with data rates up to 54Mbps. Counterintuitively, 802.11a came out later than 802.11b, causing some confusion in the marketplace because 802.11a eople expected that the standard with the "b" at the end would be Standards backward compatible with the one with the "a" at the end. Released in September 1999, it’s most likely that your first home router was 802.11b, which operates in the 2.4GHz frequency and provides a data rate up to 11 Mbps. Interestingly, 802.11a products hit 802.11b the market before 802.11a, which was approved at the same time but didn’t hit the market until later. Approved in June 2003, 802.11g was the successor to 802.11b, able to 802.11g achieve up to 54Mbps rates in the 2.4GHz band, matching 802.11a speed but within the lower frequency range. Different Wireless Technology and Usage WIFI Standard Types Speed and Capability The first standard to specify MIMO, 802.11n was approved in October 2009 and allows for usage in two frequencies - 2.4GHz 802.11n (Wi-Fi 4) and 5GHz, with speeds up to 600Mbps. When you hear wireless LAN vendors use the term “dual-band”, it refers to being able to WIFI deliver data across these two frequencies. Current home wireless routers are likely 802.1ac-compliant, and operate in the 5 GHz frequency space. With Multiple Input, Multiple Output (MIMO) – multiple antennas on sending and Standards receiving devices to reduce error and boost speed – this 802.11ac (Wi-Fi 5) standard supports data rates up to 3.46Gbps. Some router vendors include technologies that support the 2.4GHz frequency via 802.11n, providing support for older client devices that may have 802.11b/g/n radios, but also providing additional bandwidth for improved data rates. Approved in December 2012, 802.11ad is very fast - it can provide up to 6.7Gbps of data rate across the 60 GHz frequency, but that comes at a cost of distance – you achieve this only if 802.11ad your client device is situated within 3.3 meters (only 11 feet) of the access point. Different Wireless Technology and Usage WIFI Standard Types Speed and Capability Also known as Wi-Fi HaLow, 802.11ah defines operation of license-exempt networks in frequency bands below 1GHz (typically the 900 MHz band), excluding the TV White Space bands. In the U.S., this includes 908-928MHz, with varying WIFI frequencies in other countries. The purpose of 802.11ah is to 802.11ah create extended-range Wi-Fi networks that go beyond typical networks in the 2.4GHz and 5GHz space (remember, lower frequency means longer range), with data speeds up to Standards 347Mbps. In addition, the standard aims to have lower energy consumption, useful for Internet of Things devices to communicate across long ranges without using a lot of energy. Also known as China Millimeter Wave, this defines modifications to the 802.11ad physical layer and MAC layer to enable operation in the China 59-64GHz frequency band. The goal is to maintain backward compatibility with 802.11ad (60GHz) when it 802.11aj operates in that 59-64GHz range and to operate in the China 45GHz band, while maintaining the 802.11 user experience. Final approval was expected in November 2017. Different Wireless Technology and Usage WIFI Standard Types Speed and Capability There are some products in the home-entertainment and industrial-control spaces that have 802.11 wireless capability and 802.3 Ethernet function. The goal of this standard is to help 802.11ak 802.11 media provide internal connections as transit links within 802.1q bridged networks, especially in the areas of data rates, WIFI standardized security and quality-of-service improvements. It reached draft status in November 2017. Known as High Efficiency WLAN, 802.11ax aims to improve the performance in WLAN deployments in dense scenarios, such as Standards sports stadiums and airports, while still operating in the 2.4GHz and 5GHz spectrum. The group is targeting at least a 4X 802.11ax (Wi-Fi 6) improvement in throughput compared to 802.11n and 802.11ac., through moreefficient spectrum utilization. Approval is estimated to be in July 2019. Also known as Next Generation 60GHz, the goal of this standard is to support a maximum throughput of at least 20Gbps within the 60GHz frequency (802.11ad currently achieves up to 802.11ay 7Gbps), as well as increase the range and reliability. The standard is expected to be approved between September and November 2019. Different Wireless Technology and Usage WIFI Standard Types Speed and Capability Called Next Generation Positioning (NGP), a study group was formed in January 2015 to address the needs of a “Station to identify its absolute and relative position to another station or stations it’s either associated or unassociated with.” The goals of the group would be to define modifications to the MAC and PHY WIFI 802.11az layers that enable “determination of absolute and relative position with better accuracy with respect to the Fine Timing Measurement (MTM) protocol executing on the same PHY-type, Standards while reducing existing wireless medium use and power consumption, and is scalable to dense deployments.” The current estimate on approval of this standard is March 2021. Otherwise known as “Wake-Up Radio” (WUR), this isn’t a crazy morning zoo-crew thing, but rather a new technology aimed at extending the battery life of devices and sensors within an Internet of Things network. The goal of the WUR is to “greatly 802.11ba reduce the need for frequent recharging and replacement of batteries while still maintaining optimum device performance.” This is currently expected to be approved in July 2020. Different Wireless Technology and Usage Bluetooth ( IEEE 802.15.1) Bluetooth is a wireless technology that is part of standards designed to transmit data at typically very short ranges, from a few inches to 33 feet (10 meters). The main purpose of technologies, such as Bluetooth, is to eliminate the cables between devices such as smart- phones and computers, which allows data to be transmitted wirelessly between, say, a computer and a printer, as well as to synchronize your smartphone and computer. Different Wireless Technology and Usage ZigBee (IEEE 802.15.4) ZigBee is a wireless communication intended for short-range transmissions based on IEEE standard 802.15.4. The ZigBee specification is designed for applications that require devices with long battery life and can transmit data at distances of between 33 and 50 feet (10 to 15 meters). ZigBee is used for automating entire commercial buildings, dramatically reducing the need for control wires from every office to a central control room on the ground level or basement. Also, environmental sensors, medical data collection devices, smoke detectors, and security systems as well as controlling industrial equipment. Different Wireless Technology and Usage RFID Radio frequency identification (RFID) is another short-distance wireless technology, developed primarily to replace the barcodes you see on nearly every product sold today. Barcodes can only store a limited amount of information, the long numbers, and sometimes letters, that are usually printed below the black and white vertical bars of the code. A key advantage of RFID over barcodes is that the information can be read from the tag regardless of whether it is visible, unlike barcodes, which require the vertical bars to be exposed to a laser beam to be read. RFID tags are small chips containing a CPU, memory, and other electronic circuitry plus an antenna. Different Wireless Technology and Usage NFC Near field communication (NFC) is very similar to RFID and, in fact, some RFID equipment is also able to read NFC tags. NFC is intended to work at an average distance of about 2 to 4 inches (about 5 to 10 centimeters) between a single tag and a device or between two capa- ble devices. The transmission speed is approximately 250 Kbps, so it is suitable for reading items like credit or debit cards and for some types of wireless communications between two NFC-enabled devices. The NFC communication protocols allow battery- powered devices to exchange information and, if authorized, both read and write data to each other using secure, encrypted communications. Designing Wireless Network 1. Conduct a site survey 2. Include capacity or total number of devices and application performance 3. Use dual radio access points 4. Load balance wireless users 5. Include network access control as part of the total system 6. Keep your firmware or network adapter driver for your wireless network devices updated 7. Consider a hi-gain antenna 8. Design to the lowest common denominator on your network Designing Wireless Network 1. Conduct a site survey 2. Include capacity or total number of devices and application performance 3. Use dual radio access points 4. Load balance wireless users 5. Include network access control as part of the total system 6. Keep your firmware or network adapter driver for your wireless network devices updated 7. Consider a hi-gain antenna 8. Design to the lowest common denominator on your network