Wireless Networking: Definition, Modes and Standards

Summary

This resource provides information on wireless networking, covering definitions, modes of operation such as Ad-hoc and Infrastructure, and various wireless standards including different generations of mobile technology. The history and evolution of Wi-Fi and mobile network standards are explained, along with their applications.

Full Transcript

Wireless Networking Definition The term wireless networking refers to technology that enables two or more computers to communicate using standard network protocols, but without network cabling. A wireless network is very similar to the wired network in that all the same pieces are still required, ...

Wireless Networking Definition The term wireless networking refers to technology that enables two or more computers to communicate using standard network protocols, but without network cabling. A wireless network is very similar to the wired network in that all the same pieces are still required,  A wireless NIC,  Access Point (similar to a wired network Ethernet Switch)  A wireless router. The only thing that's missing is the cables. There are two mode of wireless network  Ad-Hoc or Peer-to-Peer Wireless Network  Infrastructure Wireless Network Modes of Wireless Network Ad-hoc or Peer-to-Peer It consists of a number of computers each equipped with a wireless networking interface card. Each computer can communicate directly with all of the other wireless enabled computers. They can share files and printers this way, but may not be able to access wired LAN resources, unless one of the computers acts as a bridge to the wired LAN using special software. Modes of Wireless Network Ad-hoc or Peer-to-Peer cont.. It must be noted however that multiple Ad Hoc devices sharing the same SSID (“Service Set Identifier”) can be on the same Ad Hoc network, thereby extending the concept from a one-to-one network to a multi-node system of connections. Ad-Hoc Wireless Network Infrastructure Wireless Network Infrastructure networks are collections of wireless devices attached to an intermediate piece of network infrastructure, typically an access point, router, or PC running access point software. In this type of network the access point acts like a hub/switch, providing connectivity for the wireless computers. It can connect (or "bridge") the wireless LAN to a wired LAN, allowing wireless computer access to LAN resources, such as file servers or existing Internet Connectivity. Wireless LAN Types of Access Points Dedicated Hardware Access Point E.g. Lucent's WaveLAN, Apple's Airport Base Station or WebGear's AviatorPRO. Hardware access points offer comprehensive support of most wireless features Software Access Points Software which run on a computer equipped with a wireless network interface card as used in an ad-hoc or peer-to-peer wireless network Wireless Standards Wireless standards are the rules that govern the setup and operations of wireless networks. Many products conform to the following standards.  802.11a,  802.11b/g/n, and/or  802.11ac Collectively they are known known as Wi-Fi technologies. Bluetooth and various other wireless (but not Wi-Fi) technologies also exist, each designed for specific networking applications. 802.11be (Wi-Fi 7) Released in January 2024, 802.11be (aka Wi-Fi 7) is the latest standard. It's much faster than Wi-Fi 6, reaching speeds up to 46 Gbps. Wi-Fi 7 is designed to use power efficiently and handle crowded Wi-Fi areas better. While final ratification of this standard isn't expected until the end of 2024, Wi-Fi 7 devices are already available. 802.11ax (Wi-Fi 6) Branded as Wi-Fi 6, the 802.11ax standard went live in 2019 to replace 802.11ac. Wi-Fi 6 maxes out at about 10 Gbps, uses less power, is more reliable in congested environments, and supports better security. Wi-Fi 6E is an extension of this standard that adds the 6 GHz band. 802.11aj Known as the China Millimeter Wave, this standard applies in China and is a rebranding of 802.11ad for use in certain areas of the world. The goal is to maintain backward compatibility with 802.11ad. 802.11ah Approved in May 2017, this standard targets lower energy consumption and creates extended-range Wi-Fi networks that can go beyond the reach of a typical 2.4 GHz or 5 GHz network. It competes with Bluetooth, given its lower power needs. 802.11ad This standard was approved in December 2012 and is freakishly fast (several Gbits/second). However, the client device must be within 30 feet of the access point. 802.11ac (Wi-Fi 5) The generation of Wi-Fi that first signaled popular use, 802.11ac, uses dual-band wireless technology, supporting simultaneous connections on both 2.4 GHz and 5 GHz Wi-Fi devices. 802.11ac offers backward compatibility to 802.11a/b/g/n and bandwidth rated up to 1300 Mbps on the 5 GHz band plus up to 450 Mbps on 2.4 GHz. Most home wireless routers are compliant with this standard. 802.11ac is the most expensive to implement; performance improvements only noticeable in high- bandwidth applications 802.11n (Wi-Fi 4) 802.11n (also sometimes known as Wireless N) was designed to improve on 802.11g in the bandwidth it supports by using several wireless signals and antennas (called MIMO technology) instead of one. Industry standards groups ratified 802.11n in 2009 with specifications providing up to 600 Mbps of network bandwidth. 802.11n also offers a somewhat better range over earlier Wi-Fi standards due to its increased signal intensity, and it is backward-compatible with 802.11a/b/g gear. While 802.11n offers significant bandwidth improvement from previous standards and is widely supported, the use of multiple signals may interfere with nearby 802.11b/g- 802.11n Sometimes known as "Wireless N” was designed to improve on g in the amount of bandwidth supported by utilizing multiple wireless signals and antennas (called Multiple Input Multiple Output or MIMO technology) instead of one. Industry standards groups ratified n in 2009 with specifications providing for up to 300 Mbps of network bandwidth. 802.11n also offers somewhat better range over earlier Wi-Fi standards due to its increased signal intensity, and it is backward-compatible with b/g gear. Multiple Input Multiple Output (MIMO) 802.11g (Wi-Fi 3) In 2002 and 2003, WLAN products supporting a newer standard called 802.11g emerged. 802.11g attempts to combine the best of both 802.11a and 802.11b. 802.11g supports bandwidth up to 54 Mbps and uses the 2.4 GHz frequency for greater range. 802.11g is backward compatible with 802.11b, meaning that 802.11g access points will work with 802.11b wireless network adapters and vice versa. This standard is supported by essentially all wireless devices and network equipment in use today, and it's an expensive option. However, the entire network slows to match any 802.11b devices on the network. 802.11a (Wi-Fi 2) While 802.11b was in development, IEEE created a second extension to the original 802.11 standard called 802.11a. Because 802.11b gained popularity much faster than 802.11a, some folks believe that 802.11a was created after 802.11b. In fact, 802.11a was created at the same time. Due to its higher cost, 802.11a is usually found on business networks, whereas 802.11b better serves the home market. 802.11a supports bandwidth up to 54 Mbps and signals in a regulated frequency spectrum around 5 GHz. This higher frequency, compared to 802.11b, shortens the range of 802.11a networks. The higher frequency also means 802.11a signals have more difficulty penetrating walls and other obstructions. 802.11a (Wi-Fi 2) cont.. Because 802.11a and 802.11b use different frequencies, the two technologies are incompatible. Some vendors offer hybrid 802.11a/b network gear, but these products merely implement the two standards side by side (each connected device must use one or the other). 802.11a is also unofficially referred to as Wi-Fi 2. 802.11b and 802.11a IEEE expanded on the original standard in July 1999, creating the 802.11b specification which supports bandwidth up to 11 Mbps, comparable to traditional Ethernet. While b was in development, IEEE created a second extension to the original standard called 802.11a which supports bandwidth up to 54Mbps Because a and b utilize different frequencies, the two technologies are incompatible with each other. Some vendors offer hybrid802.11a/b network gear, but these products merely implement the two standards side by side (each connected devices must use one or the other). 802.11b (Wi-Fi 1) IEEE expanded on the original 802.11 standard in July 1999, creating the 802.11b specification. 802.11b supports a theoretical speed of up to 11 Mbps. A more realistic bandwidth of 2 Mbps (TCP) and 3 Mbps (UDP) should be expected. 802.11b uses the same unregulated radio signaling frequency (2.4 GHz) as the original 802.11 standard. Vendors often prefer using these frequencies to lower their production costs. Being unregulated, 802.11b gear can incur interference from microwave ovens, cordless phones, and other appliances using the same 2.4 GHz range. However, by installing 802.11b gear at a reasonable distance from other appliances, interference can easily be avoided. WiFi Hot Spots A hotspot is any location where Wi-Fi network access (usually Internet access) is made publicly available. You can often find hotspots in airports, hotels, coffee shops, and other places where business people tend to congregate. Hotspots are considered a valuable productivity tool for business travelers and other frequent users of network services. Technically speaking, hotspots consist of one or several wireless Access Points installed inside buildings and/or adjoining outdoor Wireless Network Security  Wi‑Fi Protected Access (WPA and WPA2) It encrypts information and makes sure that the network security key is not modified. It also authenticates users on a the network.  Equivalent Privacy (WEP) WEP is an older network security method that's still available to support older devices, but it's no longer recommended because its easy to crack.  802.1X authentication It uses an authentication server to validate users and provide network access. It can also work with WPA, WPA2, or WEP keys. This type of authentication is typically used when connecting to a workplace network. Bluetooth Its an alternative wireless network technology that followed a different development path from the family. Bluetooth supports a very short range (approximately 10 meters) and relatively low bandwidth (1-3 Mbps in practice) designed for low-power network like handheld devices. The low manufacturing cost of Bluetooth hardware also appeals to industry vendors. You can readily find Bluetooth in the networking of PDAs or cell phones with PCs, but it is rarely used for general-purpose WLAN networking due to the range and speed considerations. Worldwide Interoperability for Microwave Access (WIMAX) WiMAX is a technology standard for long-range wireless networking. The name "WiMAX" was created by the WiMAX Forum, which was formed in June 2001 to promote conformity and interoperability of the standard. The forum describes WiMAX as "a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL“. Similarly, Wi-Fi refers to interoperable implementations of the IEEE Wireless LAN standards certified by the Wi-Fi Alliance. WIMAX WiMAX is a wireless communications standard designed to provide 30 to 40 megabit-per-second data rates, with the latest update providing up to 1 Gbit/s for fixed stations. It is a part of a fourth generation, or 4G, of wireless- communication technology. WiMax far surpasses the 30- metre wireless range of a conventional Wi-Fi local area network (LAN), offering a metropolitan area network with a signal radius of about 50 km. WiMax offers data-transfer rates that can be superior to conventional cable-modem and DSL connections, however, the bandwidth must be shared among multiple users and thus yields lower speeds in practice. WIMAX IEEE 802.11 working group standards like 802.11h and 802.11j are extensions or offshoots of Wi-Fi technology that each serve a specific purpose. Bluetooth is an alternative wireless network technology that followed a different development path than the 802.11 family. Bluetooth supports a very short range (commonly 10 meters) and relatively low bandwidth (1- 3 Mbps in practice) designed for low-power network devices like handhelds. The low manufacturing cost of Bluetooth hardware also appeals to industry vendors. WiMax also was developed separately from Wi-Fi. WiMax is designed for long-range networking (spanning miles or kilometers) as opposed to local area wireless networking. The following IEEE 802.11 standards exist or are in development to support the creation of technologies for wireless local area networking: 802.11a: 54 Mbps standard, 5 GHz signaling (ratified 1999) 802.11b: 11 Mbps standard, 2.4 GHz signaling (1999) 802.11c: Operation of bridge connections (moved to 802.1D) 802.11d: Worldwide compliance with regulations for use of wireless signal spectrum (2001) 802.11e: Quality of Service support (2005) to improve the delivery of delay-sensitive applications, such as Voice Wireless LAN and streaming multimedia 802.11F: Inter-Access Point Protocol recommendation for communication between access points to support roaming clients (2003) 802.11g: 54 Mbps standard, 2.4 GHz signaling (2003) 802.11h: Enhanced version of 802.11a to support European regulatory requirements (2003) 802.11i: Security improvements for the 802.11 family (2004) 802.11j: Enhancements to 5 GHz signaling to support Japan regulatory requirements (2004) 802.11k: WLAN system management 802.11m: Maintenance of 802.11 family documentation 802.11n: 100+ Mbps standard improvements over 802.11p: Wireless Access for the Vehicular Environment 802.11r: Fast roaming support using Basic Service Set transitions 802.11s: ESS mesh networking for access points 802.11T: Wireless Performance Prediction — recommendation for testing standards and metrics 802.11u: Internetworking with cellular and other forms of external networks 802.11v: Wireless network management and device configuration 802.11w: Protected Management Frames security enhancement 802.11y: Contention-Based Protocol for interference 802.11ad: 6.7 Gbps standard, 60 GHz signaling (2012) 802.11ah: Creates extended-range Wi-Fi networks that go beyond the reach of a typical 2.4 GHz or 5 GHz networks 802.11aj: Approved in 2017; primarily for use in China 802.11ax: Approval expected 2018 802.11ay: Approval expected 2019 802.11az: Approval expected 2019 Mobile Technology Mobile technology is the technology used for cellular communication. Its a technology that allows transmission of data, voice and video via a computer or any other wireless enabled device without having to be connected to a fixed physical link. The essence of mobile computing is to work from any location. The use of ipads, Tablets, Smartphones, and notes books, have in turn pushed the demand for these devices. Modern day workers have such devices that enable them carry out their work from the confines or comfort of their present location. Mobile Hardware Mobile hardware or devices are configured to operate in full- duplex, whereby they are capable of sending and receiving signals at the same time. They don’t have to wait until one device has finished communicating for the other device to initiate communications. Mobile Software Mobile software is the actual program that run on the mobile hardware. In other terms, it is the operating system of that appliance and its the essential component that makes the mobile device operate. Examples are:  Apples’ ios  Windows Mobile  Nokia Symbian (Sold)  Google’s Android  Black Berry  Samsung Bada  LG WebOS Types of Mobile Technologies In the world of cell phones, 1G signifies first-generation wireless analog technology standards that originated in the 1980s. 1G was replaced by 2G wireless digital standards. 2G 2G signifies second-generation wireless digital technology. 2G introduced 2 basic mobile phone technology i.e. the GSM standard which stands for Global System for Mobile Communications and Code Division Multiple Access (CDMA) standard. Designed for voice only with speed up to 64kbps. It uses General packet radio service (GPRS) as its packet service which made internet browsing possible. 2.5G 2.5G wireless technology is a stepping stone that bridged 2G to 3G wireless technology. 2.5G uses Enhanced Data rate for GSM Evolution (EDGE) as its packet services. While 2G and 3G have been formally defined as wireless standards, 2.5G has not been and was created only for the purposes of marketing. 2.5G saw some of the advances inherent in 3G networks. The evolution from 2G to 3G ushered in faster and higher-capacity data transmission. 3G 3G technologies enabled faster data-transmission speeds, greater network capacity and more advanced network services. It is designed for voice with some consideration for data notably multimedia, text and internet and speeds up to 7.2Mbps. A 3G network provides for download speeds of 14.4 megabits per second and upload speeds of 5.8 megabits per second. Often denoted as 3.5G and 3.75G It’s the first mobile broadband telephony , mobile Internet access, fixed wireless Internet access, video calls and mobile TV technologies. Packet service used in 3G are 3G cont. Packet Service in 3G are Wideband Code Division Multiple Access (WCDMA), and High Speed Downlink Packet Access(HSDPA) HSDPA which is the latest packet service in 3G offers no substantial upgrade to the feature set of WCDMA, but improves the speed of data transmission to enhance those services. HSDPA allows speeds above 384kbps, the most notable of which is 3.6Mbps and 7.2Mbps, which a lot of telecommunications companies often advertise. In truth, HSDPA is capable of reaching much higher speeds depending on the type of modulation that is being used. HSDPA speeds can even reach a theoretical maximum of 84Mbps. 4G In addition to the usual voice and other services of 3G, a 4G provides mobile ultra-broadband Internet access, for example to laptops with USB wireless modems, to smartphones, and to other mobile devices. Conceivable applications include amended mobile web access, IP telephony, gaming services, high-definition mobile TV, video conferencing, 3D television, and cloud computing 4G Two 4G candidate systems are commercially deployed: the Mobile WiMAX standard (first used in South Korea in 2007), and the first-release Long Term Evolution (LTE) standard (in Oslo, Norway and Stockholm, Sweden since 2009). It has however been debated if these first-release versions should be considered to be 4G or not.