Wireless & Mobile Computing- Deployment Issues & Challenges

1. Wireless & Mobile Computing-Deployment Issues & Challenges

2. Wireless Andrew Project Overview Chuck Bartel

3. Carnegie Mellon Background • Private research university (R1) • 50+ buildings on 100+ acre campus • Half of buildings are on contiguous main campus

4. Background -- 1994 • Dozens of Mobile, Wearable, and Wireless Computing Projects • Multidisciplinary Collaboration Spanning Several Campus Buildings • More than $20M in Research Funding • No Comprehensive Network-- Each Research Project Left to Fend for Itself

5. Vision -- 1994 • Establish Common Research Network • NSF Grant - $550,000 over 2 years • Build an Experimental, High-Speed, Wireless Network • Support research projects in wireless communication and mobile computing.

6. Implementation -- 1995-1998 • No Standard Existed for Wireless LANs • Evaluation + Selection: ATT/Lucent 915Mhz • Deployed network in 5 campus buildings • Enable use by approximately 150 users • Research Network = Limited Support

7. Background -- 1998 • Successful Wireless Research Network • Growing use of Laptops • Need for Wireless Production Network • Wireless LAN Standard 802.11 Adopted by IEEE • Lucent Grant to Support Campus-Wide Deployment (400 Access Points/cards)

8. Implementation -- 1998-2000 • Deploy Network Campuswide • 30+ Buildings (2.8M sq ft) + Outdoor Areas • Use by Virtually Anyone on Campus • Provide Support Equivalent to Wired Network • Lucent’s WaveLAN Product -2.4GHz, IEEE 802.11 Compliant

9. Deployment Issues & Challenges

10. Key Components- Wireless LAN Access Point - network device that links wireless stations to the wired network -- $900/unit Wireless NIC cards- EISA bus or PC card -radio transceivers for the end users -- $795/card $595/card $275/card $125/card

11. Wireless doesn’t necessarily mean Without Wires • For every Access Point in a building, we need: • 110 vac plug • Data cable capable of supporting a 10BaseT connection • Since most of the Access Points end up above ceilings or other out of the way places, new dedicated cables needed to be installed. • Avg. cost per installed • AP $1.9K (Cost of AP- $.9K)

12. Design factors to consider • Interference • Mobility – Roaming • Coverage vs Capacity

13. Interference Examples of potential interference sources in the 2.4GHz ISM band (IEEE 802.11) • Microwave ovens • 2.4GHz Cordless phones • Bluetooth • Other 802.11 LAN devices • Other 2.4GHz LAN devices How do you regulate these on your campus? Can you? Should you?

14. Other complicating factors • Mobility complicates wireless designs. • Wireless design is as much Art as Science. • The wireless industry is evolving their products to support campus environments (but they are still behind the wired side of networking).

15. Keys to Design Success (for CMU) We developed new approaches to building-wide wireless design with the vendor. • Colorized coverage maps • Design review meetings • Designed for coverage (not for capacity) Based on our experiences, the vendor improved their design tools.

17. Design Futures The “Walkabout” WLAN Design Tool Alex Hills Carnegie Mellon University

18. CMU’s Manual Design ProcessEnhances WLAN Performance • Complete coverage • no gaps • Minimize co-channel overlap • capacity • Lucent design manual based on process developed at CMU

19. What Is Needed To Improve Design Process • A design process that is: • Fast • Easy to use • Correct! • The “Walkabout” tool: • Is much faster than manual process • Requires minimal training • Requires no building drawings • Uses inexpensive hardware

20. Walkabout Hardware Requirement • Notebook computer • Harness • Position locator

21. Walkabout Development Phases • Phase I • Creates coverage map • Assigns frequencies to APs • Phase II • Predicts coverage map (“what if”) after APs moved to new locations • Phase III • Recommends “first cut” design

22. Walkabout Phase I Tool • Temporarily position APs • Walk around target space • single floor building • multi-floor building • outdoor space • Results: • Coverage map • Frequency assignment

23. Multi AP Display

24. For more info contact: Alex Hills Carnegie Mellon University (412) 268-2122 ahills@cmu.edu

25. Wireless Andrew Infrastructure • Standards-Based Wireless LAN in all Academic and Administrative Buildings • Comprehensive Coverage with Roaming Enabled (Mobility is Seamless) • Wireless LAN is Connected to the Campus Backbone and Internet • Supporting 600-1000 Users • Add’l Info available at URL: http://www.cmu.edu/computing/wireless

27. Where are we now? • We cover 14+ buildings (to date)- 240 APs • We cover over 2 M sq. ft. of office/lab/classroom space • We cover roughly 60% of the academic campus. • We have 800+ users We will be adding another 16 bldgs. ( 800K sq. ft.) by 6/30/2000. –Approx. 84 APs

28. Wireless Campus by June Academic andAdministrative Buildings Residence Halls, Parking, etc

29. How Much?? $$$, coverage • Average cost of wireless: <$1K for AP, <$1K for power/data install, + wired network infrastructure costs+design labor costs. • Avg pwr/data install schedule– 8 locations / wk • Avg AP installs - 8 per day • AP to sq.ft. density: depends on building construction and arch concerns, ex: older construction 25 A.P.s cover 228Ksq.ft., newer construction 12 A.P.s cover 210Ksq.ft. • Best coverage 17.5Ksqft/AP, Worst 3.4Ksqft/AP • Your mileage WILL VARY!!!

30. Q & A

31. Wireless Andrew Issues/Futures • Coverage vs capacity – Why not both? • “Airspace policy” and interference –Bluetooth,… • Keeping up with demand- scaling issues • Security-Authentication • Next Gen 802.11(a) –5Ghz Issues: Fork-lift upgrade? Ease of transition? John Schafer will cover some of these topics

32. Uses of wireless infrastructure • Untethered access to campus network: • Follow-on project - Handheld Andrew: enhancing usability of palm and HPCs with access to campus network – • Researcher’s “Field of Dreams” Tracy Futhey will cover some of these topics

33. Wireless “Bake-off”

34. Penn State Wireless Experiences Russell Vaught