Wireless Presented by John E. Janes
What is wireless? Anything without wires!!
Common Uses • Cellular phones and pagers -- provide connectivity for portable and mobile applications, both personal and business • Global Positioning System (GPS) -- allows drivers of cars and trucks, captains of boats and ships, and pilots of aircraft to ascertain their location anywhere on earth
Common Uses • Cordless computer peripherals -- the cordless mouse is a common example; keyboards and printers can also be linked to a computer via wireless • Cordless telephone sets -- these are limited-range devices, not to be confused with cell phones
Common Uses • Home-entertainment-system control boxes -- the VCR control and the TV channel control are the most common examples; some hi-fi sound systems and FM broadcast receivers also use this technology • Remote garage-door openers -- one of the oldest wireless devices in common use by consumers; usually operates at radio frequencies
Common Uses • Two-way radios -- this includes Amateur and Citizens Radio Service, as well as business, marine, and military communications • Baby monitors -- these devices are simplified radio transmitter/receiver units with limited range
Common Uses • Satellite television -- allows viewers in almost any location to select from hundreds of channels • Wireless LANs or local area networks -- provide flexibility and reliability for business computer users
Common Uses • Fixed wireless -- the operation of wireless devices or systems in homes and offices, and in particular, equipment connected to the Internet via specialized modems • Mobile wireless -- the use of wireless devices or systems aboard motorized, moving vehicles; examples include the automotive cell phone and PCS (personal communications services)
Common Uses • Portable wireless -- the operation of autonomous, battery-powered wireless devices or systems outside the office, home, or vehicle; examples include handheld cell phones and PCS units • IR wireless -- the use of devices that convey data via IR (infrared) radiation; employed in certain limited-range communications and control systems
Definitions • IEEE – (Institute of Electrical and Electronics Engineers). An organization composed of engineers, scientists and students best known for developing standards for the computer and electronics industry – in particular the IEEE 802 standards for Local Area Networks. • PDA – Personal Digital Assistants. Communications devices that often incorporate a multitude of services & functions such as contacts, email, calendaring, paging, phone services, web browsing, multi-media services and access to enterprise applications.
Definitions • SSH – Secure Shell. A program designed to allow users to log into another computer over a network to execute commands on that computer and to move files to and from that computer. SSH encrypts everything it sends across the network. • SSID – Service Set Identifier. A unique identifier attached to the header of packets sent over a wireless LAN that acts as a password when a mobile device tries to connect to a wireless receiver. Sometimes referred to as the Network Name.
Definitions • SSL – Secure Socket Layer. An information technology for securely transmitting information over the internet or intranet. SSL encrypts communications between a user’s browser and a web server. • VLAN – Virtual Local Area Network. A collection of nodes that are grouped together in a single broadcast domain that is based on something other than physical location. A logical grouping of stations and/or switch ports, allowing communcations as if all stations/ports are on the same physical LAN segment. VLANs reduce broadcast traffic and allow more control in implementing security policies.
Definitions • VPN – Virtual Private Network. A group of two or more computer systems connected to a private network with limited public network access that communicates securely over a public network, such as the internet. VPNs include encryption, authentication of remote users/hosts and mechanisms for hiding or masking information about private network topology from potential attackers on the public network. • WEP – Wired Equivalency Privacy. A security protocol for wireless local area networks defined in the 802.11b standard.
Definitions • WI-FI Alliance – A non-profit international association formed in 1999 to certify interoperability of wireless LAN products based on the IEEE 802.11 specification. • Access Point or AP – a device that provides radio signal connectivity for wireless LAN clients and a wired network connection, bridging the wireless and wire-line networks.
Definitions • Wireless Client – a network node using wireless radio signaling to reach a network through an association with a wireless AP. • Wireless Network – one in which a mobile user can connect to a local area network through a wireless (radio) connection.
Definitions • Global System for Mobile Communication (GSM) -- a digital mobile telephone system used in Europe and other parts of the world; the de facto wireless telephone standard in Europe • General Packet Radio Service (GPRS) -- a packet-based wireless communication service that provides continuous connection to the Internet for mobile phone and computer users
Definitions • Enhanced Data GSM Environment (EDGE) -- a faster version of the Global System for Mobile (GSM) wireless service • Universal Mobile Telecommunications System (UMTS) -- a broadband, packet-based system offering a consistent set of services to mobile computer and phone users no matter where they are located in the world
Definitions • Wireless Application Protocol (WAP) -- a set of communication protocols to standardize the way that wireless devices, such as cellular telephones and radio transceivers, can be used for Internet access • i-Mode (NTT DoCoMo’s “language”) -- the world's first "smart phone" for Web browsing, first introduced in Japan; provides color and video over telephone sets
Definitions • BlueTooth (open standard for short-distance transmission of digital voice & data) • CDMA (Code Division Multiple Access)
Definitions • 1G (first Generation) wireless: analog cell phones - AMPS, TACS and NMT • Advanced Mobile Phone Service • Total Access Communication System • Nordic Mobile Telephone • 2G (second Generation) wireless: digital cellphones - GSM, TDMA and CDMA • Global System for Mobile communications • Time Division Multiple Access • Code Division Multiple Access
Definitions • CDPD (Cellular Digital Packet Data) an overlay of the TDMA networks – enables TCP/IP; sometimes called wireless IP • 2.5G, 2G+Interim stage between 2G and 3G, providing faster data services – GPRS, EDGE • General Packet Radio Service • Enhanced Data rates for Global Evolution • 3G includes UMTS, cdma2000and NTT DoCoMo • Universal Mobile Telecommunications System
Definitions • PAN (Personal Area Network) – small networks • m-commerce – mobile commerce (buzzword) • BREW (Binary Runtime Environment for Wireless) new language from Qualcomm, similar to WAP • XML (eXtensible Markup Language) – similar to HTML, but it separates content between data (a name, a price, a date) and format (bold, italics, header, body of document)
Definitions • IR (Infra Red) – used by PDA’s and GameBoys • Digital – information turned into binary form (0’s and 1’s) can be electronically manipulated, preserved and regenerated perfectly at high speed • Analog – A representation of an object that resembles the original, with each copy, deterioration occurs
The ABGs of Wireless • As you shop for wireless equipment, you'll be faced with a choice of equipment compatible with the slew of wireless network standards--namely 802.11a, 802.11b, and 802.11g. Here's the skinny: • 802.11 is a family of specifications for wireless networks developed by the IEEE. There are currently four specifications in the family: 802.11, 802.11a, 802.11b and 802.11g. 802.11a, 802.11b, and 802.11g represent three popular wireless communication standards. Wireless networks can be built using any of the three, but 802.11a is less compatible with the others and tends to be a more expensive option implemented only by larger businesses.
The ABGs of Wireless • The 802.11a standard offers data speeds up to 54 mbps, but it isn't compatible with 802.11b or 802.11g devices. It uses the FCC unlicensed 5GHz National Information Infrastructure (U-NII) band.
The ABGs of Wireless • The 802.11b standard has been around since 1998 and is by far the most widely used wireless network standard today. As a result, equipment based on 802.11b is generally less expensive than 802.11a and the newer 802.11g devices. And you're less likely to experience compatibility issues with 802.11b-based wireless equipment. It uses the FCC unlicensed 2.4GHz Industrial, Scientific, Medical (ISM) band.
The ABGs of Wireless • The newer 802.11g standards offer faster data transfer speeds than 802.11b. It uses the FCC unlicensed 2.4GHz Industrial, Scientific, Medical (ISM) band.
The ABGs of Wireless • Consider this: A wireless network using 802.11b equipment is supposed to deliver data transfer rates up to 11 megabits per second. But a recent ComScore Networks study found that the average data transfer speed of a cable modem is 708 kilobits per second and the average DSL speed is only 467 kbps. Without delving for too much precision, that means 802.11b is more than 15 times faster than cable and 23 times faster than DSL.
The ABGs of Wireless • Offering data transfer rates up to 54 mbps, 802.11g is essentially a faster version of 802.11b. Devices based on the new 802.11g standard are compatible with 802.11b equipment. If you buy an 802.11g network adapter card for your laptop, for instance, it will work with 802.11g devices as well as 802.11b-based wireless networks, such as those served up at Starbucks, though at the slower speed, of course.
The ABGs of Wireless • Both 802.11g and 802.11b devices share the same radio spectrum as 2.4-GHz portable phones and microwave ovens, which may cause some slight network interference. For instance, if you're wirelessly transmitting multimedia files, such as MP3s, from your computer to your stereo set, you may notice some dropped notes on occasion. Otherwise, though, you probably won't experience any truly noticeable interference.
The ABGs of Wireless • Also worth noting: 802.11a typically offers a range of only 200 feet, compared with the 300-foot range of 802.11b and 802.11g devices. (As with any Wi-Fi network equipment, the farther you roam from a wireless access point, the weaker the signal and the slower your connection speed.)
The ABGs of Wireless • Does anyone really need the faster speeds that 802.11a and 802.11g offer? If you're interested in installing a wireless home media network to send streaming video and audio from one device to another, the answer is yes. Large media files need all the bandwidth they can get.
The ABGs of Wireless • If you want to hedge your bets, consider buying dual-band wireless networking equipment. These devices support both the 802.11a and 802.11g (and thus, 802.11b) standards but are generally more expensive.
The ABGs of Wireless • And now 802.11n • not official yet but 802.11n is likely to be the designation of a high-throughput variant of the 802.11 standard. the primary concern here being real world performance vs theoretical throughput. • ie: 802.11b is 11M/bits/s, but due to overhead the actual, real world performance is only ~5.5Mbits/s. now 5.5 is plenty fast (around 3.5 T1's), but in a world of Voice over IP (VoIP) that is only ~90 calls at a time... so in larger implementations where you have high client density 802.11a,g,n would prove critical in supporting heavy usage by hundreds of clients... this would be important for say an ISP setup. • so 802.11n is proposed to run with a real world performance of at least 108Mbits/s... now that is what i call industrial strength...
Wireless Terms & Jargon • What is a WLAN? • a "typical" wireless home network. That's because a WLAN is a wireless LAN, and a LAN is a related group of networked computers situated in close physical proximity to each other. LANs can be found in many homes, schools, and businesses. Though it's technically possible to have more than one LAN in your home, few do this in practice.
Wireless Terms & Jargon • What is Wi-Fi? • Wi-Fi is an industry name used to market wireless networking products. You'll find a black-and-white Wi-Fi logo or certification emblem on virtually any new wireless equipment you buy. Technically speaking, Wi-Fi signifies conformance to the 802.11 family of wireless communication standards. But because all mainstream wireless home network gear uses the 802.11 standards today, basically the term "Wi-Fi" merely distinguishes wireless equipment from other network gear.
Wireless Terms & Jargon • What are WEP? • WEP is an important feature of wireless networks designed to improve security. WEP scrambles (technically speaking, encrypts) network traffic mathematically so that other computers can understand it, but humans cannot read it. WEP helps protect your WLAN from wardrivers and nosy neighbors, and today, all popular wireless equipment supports it. Because WEP is a feature that can be turned "on" or "off," you'll simply need to ensure it is configured properly when setting up your network.
Wireless Terms & Jargon • What is WPA? • Short for Wi-Fi Protected Access, a Wi-Fi standard that was designed to improve upon the security features of WEP. The technology is designed to work with existing Wi-Fi products that have been enabled with WEP (i.e., as a software upgrade to existing hardware), but the technology includes two improvements over WEP: • Improved data encryption through the temporal key integrity protocol (TKIP). TKIP scrambles the keys using a hashing algorithm and, by adding an integrity-checking feature, ensures that the keys haven’t been tampered with.
Wireless Terms & Jargon • What is WPA? • User authentication, which is generally missing in WEP, through the extensible authentication protocol (EAP). WEP regulates access to a wireless network based on a computer’s hardware-specific MAC address, which is relatively simple to be sniffed out and stolen. EAP is built on a more secure public-key encryption system to ensure that only authorized network users can access the network. • It should be noted that WPA is an interim standard that will be replaced with the IEEE’s 802.11i standard upon its completion.
Wireless Terms & Jargon • What are Wardriving? • A few years ago, some techies popularized the practice of wardriving to raise awareness of this vulnerability in WLANs. With the help of cheap, home-made equipment, "wardrivers" walked or motored through neighborhoods snooping the wireless network traffic emanating from nearby homes. Some wardrivers even logged their computers onto unsuspecting people's home WLANs, essentially stealing free computer resources and Internet access.
Wireless Terms & Jargon • Wireless Network Adapters • Each computer you wish to connect to a WLAN must possess a wireless network adapter. Wireless adapters are sometimes also called NICs, short for Network Interface Cards. Wireless adapters for desktop computers are often small PCI cards or sometimes card-like USB adapters. Wireless adapters for notebook computers resemble a thick credit card. Nowadays, though, an increasing number of wireless adapters are not cards but rather small chips embedded inside notebook or handheld computers.
Wireless Terms & Jargon • Wireless Network Adapters • Wireless network adapters contain a radio transmitter and receiver (transceiver). Wireless transceivers send and receive messages, translating, formatting, and generally organizing the flow of information between the computer and the network. Determining how many wireless network adapters you need to buy is the first critical step in building your home network. Check the technical specifications of your computers if you're unsure whether they contain built-in wireless adapter chips.
Wireless Terms & Jargon • Wireless Access Points • A wireless access point serves as the central WLAN communication station. In fact, they are sometimes called "base stations." Access points are thin, lightweight boxes with a series of LED lights on the face. • Access points join a wireless LAN to a pre-existing wired Ethernet network. Home networkers typically install an access point when they already own a broadband router and want to add wireless computers to their current setup. You must use either an access point or a wireless router to implement "hybrid" wired/wireless home networking. Otherwise, you probably don't need an access point.
Wireless Terms & Jargon • Wireless Routers • A wireless router is a wireless access point with several other useful functions added. Like wired broadband routers, wireless routers also support Internet connection sharing and include firewall technology for improved network security. Wireless routers closely resemble access points.
Wireless Terms & Jargon • Wireless Routers • A key benefit of both wireless routers and access points is scalability. Their strong built-in transceivers are designed to spread a wireless signal throughout the home. A home WLAN with a router or access point can better reach corner rooms and backyards, for example, than one without. Likewise, home wireless networks with a router or access point support many more computers than those without one.
Wireless Terms & Jargon • Wireless Antennas • Wireless network adapters, access points, and routers all utilize an antenna to assist in receiving signals on the WLAN. Some wireless antennas, like those on adapters, are internal to the unit. Other antennas, like those on many access points, are externally visible. The normal antennas shipped with wireless products provide sufficient reception in most cases, but you can also usually install an optional, add-on antenna to improve reception. You generally won't know whether you'll need this piece of equipment until after you finish your basic network setup.
Wireless Terms & Jargon • Wireless Signal Boosters • Some manufacturers of wireless access points and routers also sell a small piece of equipment called a signal booster. Installed together with a wireless access point or router, a signal booster serves to increase the strength of the base station transmitter. It's possible to use signal boosters and add-on antennas together, to improve both wireless network transmission and reception simultaneously.
Wireless Terms & Jargon • A New Wireless Revolution: Enter The WiMAX Zone • A new revolution is coming down the pike: WiMAX. Why would you want WiMAX? Well, they chose the name correctly, as it's Wi-Fi "to the max". This new standard makes Wi-Fi look puny: 25x broadband speed (75Mbps), and a maximum range of a whopping 30 miles. (Your mileage may vary) It goes through walls, trees, clouds and does not need line of sight. But it isn't long distance Wi-Fi. The two standards are not compatible, so that means completely new hardware. If you want to use both you'd need a WAP that supports both. The official name of this one is 802.16 and it operates below 11GHz. You can pretty much expect a second WiMax wave starting in 2006, leading to a Billion dollar market in 2008.
Wireless Terms & Jargon • A New Wireless Revolution: Enter The WiMAX Zone • Is this tested technology? Yes, some of the big phone companies in Europe are testing this and some wireless service providers have WiMax networks up in New Your City and Montana. But it's "fixed" to start with, mobile will come a lot later. Expect this to compete with current Wi-Fi hotspots, but now you'll see a whole city being covered with just a few of these access points, think 2007. Don't think it's the only new standard though. There are other people out there pushing other stuff. But WiMAX is backed by Intel.
Wireless Terms & Jargon • BlueTooth - What it is? • Whereas wi-fi is a LAN (local area networking) technology, BlueTooth is known as PAN (personal area networking) technology. The distance range is much less, about 33 feet. BlueTooth is generally used to connect devices that are within the same room or close by. For example, you can use it to connect your PDA to a BlueTooth enabled phone or you can print to BlueTooth enabled printers (without wires). Like 802.11b, BlueTooth is an RF (Radio Frequency) wireless technology that operates on the 2.4GHz band. However, BlueTooth and wi-fi devices can usually operate in the same vicinity without interference, and do not communicate with each other.