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WIRELESS NETWORK TECHNOLOGIES

WIRELESS NETWORK TECHNOLOGIES. Group B Maj Marek Sipko Capt Billy Hortman Capt Michael McFerron LT Mark Bjerke LTjg David Jackson. Topics. History Standards Security Bluetooth Future. History of Wireless Technology. The beginning….

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WIRELESS NETWORK TECHNOLOGIES

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  1. WIRELESS NETWORK TECHNOLOGIES Group B Maj Marek Sipko Capt Billy Hortman Capt Michael McFerron LT Mark Bjerke LTjg David Jackson

  2. Topics • History • Standards • Security • Bluetooth • Future

  3. History of Wireless Technology

  4. The beginning… • Most credit Guglielmo Marconi, “the father of radio”, with the initiation of wireless technology • 1894 Marconi experimented with Hertzian Waves (radio waves) to produce and detect waves over long distances • 1896 Marconi established the Wireless Telegraph & Signal Company, the first radio factory • 1901 St John’s, New Foundland, Marconi received the first trans-Atlantic wireless signal from Poldhu, England • 1905 the first distress signal sent using Morse Code • 1919 Radio Corporation of America (RCA) was incorporated, and consumer radio broadcasts for news and entertainment soon became popular

  5. US Military jumps into Wireless • During World War II the US Military used wireless signals with encryption to send battle plans and instructions • US Military started the shift to radio data transmission technology

  6. Wireless Networking: Birth of the Wireless Network • 1971 network technologies met radio technologies when the first wireless Local Area Network (LAN) was established at the University of Hawaii during the experiment, ‘ALOHANET’ • ALOHANET used a bidirectional star topology consisting of (7) computers over (4) islands

  7. Wireless Networking: Cellular • 1973 Dr Martin Cooper, Motorola Labs, invented the first personal mobile cellular telephone (weighed 2.5 lbs, 30 individual circuit boards, no display screen, 9”x5”x1.75”, 10 hours to charge for 35 minutes of use) • 1983 marked American entry into the commercial cellular service market • 1987 FCC allows and encourages cellular service providers to use alternate technologies in the 800Mhz radio spectrum to prompt use of digital transmission

  8. Wireless Networking: IEEE • 1990 IEEE 802 Executive Committee established the 802.11 Working Group to create a wireless LAN standard. • 1997 working group approved IEEE 802.11 as the world’s first wireless LAN standard • New standards are continuously being developed by the Institute of Electrical and Electronical Engineers

  9. History: Timeline 1905 – first distress signal successful using Morse Code 1987 – FCC encourages use of 800Mhz spectrum 1896 – Wireless Telegraph & Signal Company established 1939-1945 – WWII US Military initiates radio data transmission technology 1997 – 802.11 established as wireless LAN standard 1973 – Motorola creates first mobile cellular telephone 1894 – experiments began with Hertzian Waves 1919 – RCA incorporated 1971 – ALOHANET experiment, first wireless LAN 1990 – IEEE creates work group to establish wireless LAN standards 1901 – first trans-Atlantic signal received 1983 – America enters cellular telephone market

  10. Wireless Standards IEEE 802.11n

  11. Current IEEE1 Standards • 802.11b- Actually the first of the 802.11 standards. • Max Speed 11MB/sec. 128 bit encryption. 2.4 Ghz operating frequency. • 802.11a- Best suited for large businesses concerned with security • 54 MB/sec max speed. 5 Ghz operating frequency. 152 or 256 bit level of encryption. • 802.11g- Best of both worlds for the average user. • 2.4 Ghz, 54 MB/sec, 128 bit encryption.

  12. IEEE 802.11x

  13. Standards currently being utilized

  14. Crafting Changes • IEEE Fall of ’03 • Launched a working group to develop new standard (802.11n). • Major goal: • Increase WLAN throughput to at least 100MB/sec. • Throughput- Defined as data rate minus IP overhead.

  15. Overhead • Typically “overhead” can eat up half of the data rate. • 802.11 b, a, and g- • b- 11 MB/sec yields <6MB/sec throughput • a and g yield 18-22 MB/sec.

  16. 802.11n • Benefits- • To make WLANS “feel like” 100MB/sec. • Promotes the idea that wireless networks may someday entirely replace wired ones. • Saves money in the long run by eliminating cabling costs.

  17. 802.11n • Challenges- • Delivering higher performance while simultaneously reducing cost. • Throughput still can be reduced- • Wood, metal etc. inside buildings still a factor. • Skeptics- • Unless one sitting underneath the access point, still won’t get the max throughput. • Access points will still need to be hard wired to wiring closets.

  18. 802.11n • Bottom Line- • Speed is going to happen, just a matter of time. • Expect to see 802.11n within 18 months. • Expect your connection at home to “feel” 5 to 10 times faster than it does right now.

  19. Security of Wireless Networks Two basic steps: • A host system needs to authenticate the user or device that it's communicating with. • The data must be protected as it travels from the user device to the destination host, whether to preserve confidentiality or to ensure that the message isn't changed or destroyed en route.

  20. Antenna Effects An intruder must be within range of the signal to cause problems. Proper positioning of an antenna within a building can minimize the possibility of reception by an outside source.

  21. Security Risks • Insertion Attacks - placing unauthorized devices on the wireless network without going through a security process • Interception and Monitoring wireless traffic - these vary between sniffer, hijacking a session, broadcast monitoring, and base station cloning • Misconfiguration - administrators can leave factory settings in tact which are the least secure • Jamming - illegitimate traffic overwhelms frequencies, and legitimate traffic can not get through • Client to Client Attacks - two wireless clients can talk directly to each other by-passing the base station

  22. Solutions to Minimizing Risk • Don't use TCP/IP for File and Printer sharing! • Follow secure file-sharing practices • Enable WEP Encryption • Use WEP for data and Authentication • Use non-obvious WEP keys and periodically change them • Secure your wireless router / Access Point (AP) • Disallow router/ AP administration via wireless • Use MAC address based Access and Association control • Don't send the ESSID • Don't accept "ANY" ESSID • Use VPN http://www.practicallynetworked.com/support/wireless_secure.htm

  23. New Security Research companies continue to look for new ways to keep wireless networks secure. An example is Wireless Security Auditor (WSA) developed by IBM and described at http://www.research.ibm.com/gsal/wsa/ Others are being tested every day

  24. Bluetooth A specification adopted by the world's most powerful and influential communications and computer manufacturers. It will enable devices from mobile phones and PCs to camcorders and cookers to talk to one another.

  25. A little bit of history: • In early 1994, a team of researchers led by Sven Mattisson and Jaap Haartsen in a vibrant college town called Lund, Sweden, were investigating the possibility of developing a wireless connection between an ear-piece and phone. As development proceeded, with it came the realization that the potential of such a technology far exceeded that of a mere cordless headset. Ericsson decided to further research the technology and thus, almost by accident the Bluetooth concept was born.

  26. The Bluetooth SIG set the following goals: • Global usage • Voice and data handling • The ability to establish ad-hoc connections • The ability to withstand interference from other sources in the open band • Very small size, in order to accommodate integration into a variety of devices • Negligible power consumption in comparison to other devices for similar use • An open interface standard • Competitively low cost of all units, as compared to their non-Bluetooth contemporaries.

  27. So how does Bluetooth work? • Basically, Bluetooth works by finding out what other Bluetooth devices are nearby and then talking to them as necessary. It does this by establishing a piconet, where one device controls communications with up to seven others. Many piconets can be linked to form a scatternet .

  28. Some ideas on how Bluetooth will ingratiate itself into our lives: Data synchronization need never again be a problem as your Bluetooth enabled PDA, PC or laptop all talk to each other and update their respective files to the most recent ones. Traveling in a plane, a person may write but not send e-mail. When the plane touches down the Bluetooth enabled laptop will communicate with the user's phone and will automatically send them. Mice and keyboards will identify themselves to the computer without intervention, or could also be used to command TVs, videos or hi-fis at the touch. Use e-mail while your laptop is still in the briefcase! When your laptop receives e-mail, you'll get an alert on your mobile phone. You can also browse all incoming e-mails and read those you select in the mobile phone's display. A traveling businessperson could ask his laptop computer to locate a suitable printer as soon as he enters a hotel lobby, and send a printout to that printer when it has been found.

  29. The Reality Check • In truth, Bluetooth is merely complementary to the other technologies that permeate our lives. A universal communicator, in itself it is of little benefit, but combined with our mobile phones, PDAs and other devices, it becomes a potent technology.

  30. The Killer App for Bluetooth The eradication of wire clutter

  31. SECURITY ISSUES • Bluetooth’s abilities, for the moment at least, will be limited to domestic use. As unresolved security issues continue to loom, it is only a brave or stupid end-user that would adopt Bluetooth on anything but a trivial scale.

  32. Domestic arena offers Bluetooth a bright future People have a natural and healthy dislike for cables littering their floors, and a technology that eliminates such an eyesore and tedium for not only computers but other electronic equipment like stereo’s, TV sets, home kitchen and others.

  33. Data Synchronization The bane of those who work on the same projects and files on different devices should be made almost ridiculously easy by Bluetooth. Merely having the different devices - PC, laptop, PDA, whatever - within about 10 meters of each other should suffice as they all automatically update their copy to the most recent one.

  34. The Radiation Issues • It is a matter of concern to some that the carrier waves used by Bluetooth inhabit the same band as that of microwave ovens. • Fortunately, the transmitting power is far too weak to result in perceptible effects in humans. Moreover, the radiation is not concentrated in a single beam; rather, it is randomly dispersed in all directions.

  35. Security Issues and Bluetooth • The three principal security features employed by Bluetooth are: • Frequency hopping, thus making eavesdropping almost impossible. • Authentication, allowing a user to control connectivity to specified devices only. • Encryption, utilizing a 0-bit, 40-bit or 64-bit key. • Despite considerable investment in this area, significant security holes still exist in the 1.1 implementation of Bluetooth.

  36. The Real Security Threat • A more real concern lies in the method needed to establish piconets. The necessity of PIN code entry in the initialization process of two Bluetooth devices is sloppy at best. The problem is augmented if each device in a scatternet or larger-sized piconet has to be independently initialized. It also poses significant problems for a network administrator - it is unlikely that a unique PIN would be assigned to each device, but not doing so would seriously compromise network integrity. It is worth noting that the SIG maintain that hackers would have to take "extreme measures" to perform this kind of hacking.

  37. Security Bottom Line • Bluetooth in its current form is unsuitable for the transfer of sensitive data. The Bluetooth SIG is actively seeking to implement more sophisticated security protocols.

  38. Tech Specs • Frequency Range • Physical Layer • Noise Immunity • Error Control • Data Transmission • Power

  39. Frequency Range • Bluetooth devices utilize the 2.4Ghz Industrial, Scientific, and Medical (ISM) frequency range. Throughout most of the world this band is free and unregulated. • Encouraged by the Bluetooth SIG, governments world-wide are now beginning to regulate the 2.4Ghz band, thus ensuring that it will remain available for unhindered use by Bluetooth appliances.

  40. Physical Layer • The Bluetooth hardware is comprised of a single 9*9mm chip. Inserted into any device it can communicate with any other Bluetooth device within a 10m radius, or up to 100m if an amplifier is used. The maximum data rate achievable by 1st generation technology is 1Mbps. Bluetooth appliances use Gaussian Frequency Shift Keying (GSSK) for radio frequency modulation. Judicious use of these modulation techniques should allow future generations to achieve a transfer rate of between 2 and 12Mbps.

  41. Noise Immunity • Frequency Hop (FH) spread spectrum is a method which effectively divides the frequency band into a number of hop channels. A technology that quickly hops channels minimizes potential interference. Bluetooth takes advantage of this technique by incorporating a fast frequency hopping technology with a nominal hopping rate of 1600 hops/second among 79 channels. After transmitting a packet each device hops to another frequency as determined by the master. The hopping sequence is unique to each piconet and determined by the Bluetooth Device Address (BDA) of the piconet master.

  42. Frequency Hop (FH) Spread Spectrum

  43. Error Control • Another method by which Bluetooth increases its noise immunity is that of Forward Error Correction (FEC). FEC is a method that enables a receiver to not only detect but also correct errors in a transmission. This technique is especially valuable in limiting the impact of noise on long distance links. Three error correction techniques have been so far defined in the Bluetooth specification: • 1/3 Rate FEC • 2/3 Rate FEC • Automatic Repeat Request (ARQ)

  44. Data Transmission • Bluetooth allows for data to be transmitted either synchronously or asynchronously. The Synchronous Connection Oriented (SCO) method is used primarily for voice while the Asynchronous Connectionless (ACL) method is used for data. Since SCO packets need smooth transmission, they are transmitted via reserved intervals, i.e. packets sent in groups with no interrupts.

  45. Power • Bluetooth is truly admirable for its sparing use of power. The technology limits the transmitter's power output to exactly that needed - the signal strength is dynamically modified to suit the required range. Power saving modes examined in the Bluetooth protocol provide further benefits.

  46. Bluetooth Connection Protocol • The Bluetooth connection protocol describes the set of rules by which all Bluetooth devices must abide in order to establish a link a communicate with one another. • The essence of Bluetooth is based upon dynamically configured units. Hopping very quickly between frequencies, the protocol specifically caters for many different modes to allow for minimal power consumption.

  47. Standby • Devices not connected in a piconet are in standby mode. In this mode, they listen for messages every 1.28 seconds - over 32 hop frequencies (fewer in Japan, Spain, and France due to local bandwidth regulation).

  48. Page/Inquiry • If a device wishes to make a connection with another device, it sends out a page message if the address is known, or an inquiry followed by a page message if it is unknown. The master unit sends out 16 identical page messages on 16 hop frequencies to the slave unit. If there is no response, the master retransmits on the other 16 hop frequencies. The inquiry method requires an extra response from the slave unit, since the MAC address is unknown to the master unit.

  49. Active • Simply, data transmission occurs.

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