1 / 69

Wireless LAN & Internet

July 14,2004. Wireless LAN & Internet. Anan Phonphoem, Ph.D. Assistant Professor Intelligent Wireless Network Group (IWING) http://iwing.cpe.ku.ac.th/ Computer Engineering Dept., Faculty of Engineering, Kasetsart University. Agenda . WLAN and Internet Wireless classification

Gabriel
Télécharger la présentation

Wireless LAN & Internet

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. July 14,2004 Wireless LAN & Internet Anan Phonphoem, Ph.D. Assistant Professor Intelligent Wireless Network Group (IWING)http://iwing.cpe.ku.ac.th/ Computer Engineering Dept., Faculty of Engineering, Kasetsart University

  2. Agenda • WLAN and Internet • Wireless classification • History and present of IEEE 802.11 • WLAN Security • WLAN Tendency • Case study: KUWIN

  3. WLAN and Internet

  4. Internet • Internet definition: • Network of network of network…. • Information, Communications, Business, and much more • How to access the Internet ? • Just a PC (device) and connection • Where can I connect? • Office, Home, or everywhere

  5. Internet Connection • Normally implies “Cable Connection” • Last “string” to PC • UTP cable from Ethernet card to a switch • Phone line from modem to the outlet • Or any broadband access…. • Local Area Network • WLAN is “Unwired LAN” or “No string LAN”

  6. WLAN Classification

  7. Wireless Classification WWAN GSM/ GPRS / CDMA WMAN IEEE802.16 WLAN IEEE802.11 HyperLan WPAN Bluetooth WAN WAN-MAN PAN MAN MAN-LAN LAN-PAN Pico-Cell Personal Operating Space ~50km ~2km 0km ~10m Courtesy of IEEE 802.15, Jan. 2001

  8. History and present of IEEE 802.11

  9. IEEE 802.11 Family

  10. IEEE 802.11 Family

  11. History: 802.11 Legacy • 1997: First standard • Standard name: IEEE 802.11-1997 • Updated: IEEE 802.11-1999 • Starting Point for “Standard-based WLAN” • For 2 Mbps: (fallback to 1 Mbps – Noisy): Direct sequence Spread Spectrum (DSSS) modulation • For 1-2 Mbps Frequency Hopping Spread Spectrum (FHSS) • Both operate in ISM band 2.4 GHz • FHSS, DSSS, and infrared medium

  12. 802.11b • 802.11b-1999 • Range 50 – 100 m. (depends on obstacles) • Omnidirectial antenna • Indoor / Outdoor / Point-to-point (high-gain external antennas) • Max throughput of 11 Mbit/s (5.5, 2, 1 Mbps) • Attenuation: Metal, Thick walls, Water, etc. • ISM Band 2.4 GHz; DSSS; CSMA/CA • 14 overlapping ch. (Different ch.for different countries) • 3 simultaneously ch. (such as 1, 6, and 11) • Proprietary speed extension "802.11b+" (22, 33 and 44 Mbit/s)

  13. 802.11a • 2001 (802.11a-1999) • Max throughput of 54 Mbps (Normally around 20 Mbps) • ISM Band 5 GHz (FCC may open more spectrum) • 12 nonoverlapping channels, • 8 dedicated to indoor • 4 to point to point • Not widely deployed (US. / Japan) • 802.11b popularity • Less range / More attenuation • Lack of roll back compatibility (now support a,b,and g) • In Europe considering HiperLan2

  14. 802.11g • 3rd quarter 2003 • ISM Band 2.4 GHz • Max throughput of 54 Mbps (Net 24.7 Mbps) • Fully backwards compatible with 802.11b • Dual-band / Tri-mode • supporting a, b, and g • A single wireless card / Access point

  15. 802.11 Wi-Fi • Specification defined by IEEE (not Compatibity guarantee) • A special group, Wi-Fi Alliance • Group of maufacturer • Test compatibility • Guarantees interoperability (by issue Wi-Fi Trademark) • Start with 802.11b  Dual band/Tri mode (a, b, or g) • Security standard Wi-Fi Protected Access (WPA)

  16. WLAN Security

  17. WLAN Security: Original 802.11 • Service Set IDentifier (SSID) • Simple password to identify WLAN • Need correct SSID to access • Media Access Control (MAC) address Filtering • List of MAC that allow to use • Wired Equivalent Privacy (WEP) • An encryption scheme • Have some flaws

  18. WLAN Security: 802.1x • Provides secure access using port control • Provides EAP (Extensible Authentication Protocol) • Supports Kerberos, smart cards, one-time password • Require mutual authentication from users via access point to RADIUS (Remote Authentication Dial-in user Service) • Improved WEP • Employ dynamic keys (instead of static keys)

  19. WLAN Security: WPA • Wi-Fi Protected Access (WPA) • By Wi-Fi Alliance • Design to run on existing HW as a SW upgrade • Derived from upcoming 802.11i • Deployed in WLAN products for software download

  20. WLAN Security: WPA • Operate in 2 modes • Enterprise mode • Need network server • Sophisticated authentication mechanism • Automatic distribution keys (Master keys) • Home mode (Pre-Shared Key) • No network server • User need to enter password (Key) – for starting point, change later • Use encryption process called Temporal Key Integrity Protocol (TKIP)

  21. WLAN Security: 802.11i • Improve WPA encryption gain • Dynamic session key • Improve authentication • Implement Advanced Encryption Standard (AES) • Message Integrity Check (MIC) • Temporal Key Integrity Protocol (TKIP)

  22. WLAN Tendency

  23. Tendency • WiMAX • Increasing speed • More WLAN security • WLAN adoption • Technology convergence • Power over Ethernet (PoE) • Wireless LAN Hot Spot • Killer applications ???

  24. Wireless Last Mile • IEEE 802.16a (WiMAX) • Last mile access (besides xDSL and cable modem) • Wireless point-to-point link • With directional antenna • Improve non-line of sight performance (eg. tree) • Install on house not the tower • Operating frequency < 11 GHz • Range up to 40 Km • Throughput up to 75 Mbps • Extension for WLAN usage

  25. Need for speed • For 802.11, the overhead more than half of the data rate • 802.11b Max 11 Mbps; Actual 6 Mbps • 802.11a,g Max 54 Mbps; Actual 22 Mbps • 802.11n • Aims at 100 Mbps (raw throughput) • Reducing power and cost • Replace wire

  26. More WLAN security: wireless worm • Blaster and Nachi Experience • Normally treated end user (desktop and notebook) as the target of malicious code • Treats end user as transmission points for attacks on the network infrastructure

  27. More WLAN security: wireless worm • Mobile users • Connected to unprotected Internet connections • Bring infected machines to logged in to corporate networks • Networks • Firewall and Intrusion-Detection System software • Routers/Switches need to protect the network • Implement software client such as “Cisco Trust Agent” • Trust Agent collects info from security software clients and relays that info to network devices • Routers/Switches enforce access privileges (denied / quarantined / limited access)

  28. Security Standards Interoperability Lack of Awareness Lower Costs Employee Demand Security Solutions Stabilizing Standards Intel & Microsoft $$ WLAN Adoption Adoption Time

  29. By Visiongain Technology Convergence • 26% of New PCs will be Labtop or Tablet PC • By 2006, 90% laptops will include Wi-Fi Capability • Internet led technology convergence • SMS and TV () • Interactive TV (Interactive Chat/Games/Program Guides)

  30. Power over Ethernet (PoE) • IEEE 802.3af (June 2003) • Major LAN Switch; IP Telephony; WLAN • Two delivery methods • Mid-Span • DC 48 volts • Unused wire pairs (Cat 5 and Cat 6) • End-Span • DC 48 volts over used pairs (different freq.) • Built in new switches • Support FastEthernet / Gigabit Ethernet

  31. Power over Ethernet (PoE) http://www.nwfusion.com/news/2003/1124infrapoe.html

  32. Wireless Hot Spot • Public places • Top-rated hotels and restaurants • Colleges / Universities • In-building antenna systems to support various wireless technologies (Wi-Fi/cellular) • Wireless friendly environmental hot spot • KUWiN (Kasetsart University Wireless Network http://kuwin.ku.ac.th) • http://www.wi-fihotspotlist.com/

  33. Enterprise VoIP Enterprise VoIP • New technology to replace existing solutions • Well-known user expectations • Emphasis on meeting traditional PBX reliability and functionality • Good migration strategies

  34. Router Corporate LAN Internet PSTN PSTN Internet Router Server Corporate LAN Traditional LAN Server Telephony Server Proprietary IP Phones Traditional PBX Proprietary Digital Phones VoIP Traditional Telephony VoIP

  35. Enterprise wireless Enterprise wireless • New technology for new applications • Developing user expectations • Emphasis on solving deployment issues and lowering cost • Disruptive technology

  36. Enterprise wireless Enterprise VoIP Voice over Wireless LAN http://www.spectralink.com Voice Over WLAN (VoWLAN)A Killer Application for WLAN ?

  37. Case Study: KUWIN

  38. Agenda • Background and Milestones • Deployment issues • System developments • Applications • Conclusion/Future Issues

  39. Established in 1943, KU celebrates the 60th anniversary last year • 7 campuses with 38,000+ students, 3000+ academic staffs, 4000+ supported staffs • 4 established campuses : Bangkhen, KampaengSaen, SriRacha and Sakhon Nakorn Province campus • 3 campuses projects : SupanBuri, LopBuri, and Krabi • 2 Demonstration schools : Bangkhen and Amata City Kasetsart University Background

  40. Bangkhen Campus • 194 buildings on 568,173 m2 • 14 Faculties (130 buildings) • 1 Graduate school (1 building) • 5 Offices (9 buildings) • 4 Institutes (16 buildings) • Central management (38 buildings)

  41. Internet Japan 2 Mbps 24 Mbps UniNet NECTEC 155 Mbps 155 Mbps Bangkhen 1.5 Mbps 1 Mbps 2 Mbps 512 Kbps 2 Mbps SriRacha SakonNakhon Kampaengsaen NontriNet • Gigabit backbone • Multicast enabled • VoIP enabled

  42. Implementation Phase I: 2000-2001 • Followed IEEE 802.11b standard • Deploy network in 2 campuses • SakhonNakorn : 5 APs in 5 Buildings • Bangkhen : • 6 APs in CPE and 2 APs in OCS (2000) • 8 APs in Rector’s office for e-meetings (2001) • Enable use by approximately 80 users

  43. Implementation Phase II : 2002 • Deploy network campus wide • 30 APs installation in 18+ buildings • Check out wireless LAN cards from main library : Birth of KUWiN • Open for everyone on campus 19 Sep 2002:Launch KUWiN at Main Library

  44. Implementation Phase III : 2003 • More APs installation… • 40 APs at every academic and administrative building in Bangkhen • 2 APs in Kampangsaen (only for executives) • Provide information and technical support equivalent to wired network

  45. KUWiN Current Status • No. of APs : approximately 120 • No. Building installed : 43 • Coverage Area : ~800,000 m2 • Wireless users : 859 • Wireless cards : 1236 • Status : March 31, 2004

  46. How much does it cost? • Approximate investment • ~3M Baht for APs + wired network • ~0.5M Baht for fiber optics expansion • ~1M Baht for new switches expansion • ~0.7M Baht for wireless LAN cards (140+ units) • Not included… • Survey and design labor costs • System development

  47. Agenda • Background and Milestones • Deployment issues • System developments • Applications • Conclusion/Future Issues

  48. Wireless Needs Wires • New dedicated cables needed to be installed. • CAT 5e UTP cable capable of supporting a 100BaseT connection • All APs utilize POE (Power on Ethernet) • Fiber optics patch cords for wireless VLANs • New fiber optics installation for some buildings

  49. Deployment • Wireless site survey by KUWiN team • Computer Center staff • Computer Engineering students • Wireless installation was handled by local contractors • Wireless team controlled the contractor’s deployment on a per-building basis

  50. Design Considerations (I) • Indoor coverage area is a primary consideration • Comprehensive coverage with roaming • Wireless must be accessible in all academic and administrative buildings • Simple to access with authentication • RADIUS authentication

More Related