copyright ©1998 alex hills 1 the “vision” of wireless access: anyone anything anytime anywhere...

Copyright ©1998 Alex Hills 1

The “Vision” of Wireless Access:

• Anyone• Anything• Anytime• Anywhere

Graphic:IEEE Spectrum


Wireless Andrew Mobile computers

(laptops -> handhelds)

Full peers

Full functionality

Full connectivity

IEEE Personal

Communications

February 1996


Wireless Technologies Cordless

Cellular

Personal Communications Services (PCS)

Paging

Wireless PBX (WPBX)

Wireless LAN (WLAN)

Packet radio

Low earth orbiting satellites (LEOS)


Wireless Technologies From Smaller to Larger Areas Room Bldg Campus City WAN

VOICE Cordless WPBX PCS/Cellular LEOS

DATA WLAN WLAN Packet Radio LEOS


Metro Area Wireless Data Options

Packet radio• ARDIS• RAM• Metricom

Cellular• Analog• CDPD

PCS • GSM


Wireless LAN

IEEE802.3

or802.5LAN

AccessPoint


Wireless LAN Characteristics Unlicensed frequencies

• 900 Mhz • 2.4 GHz• 5.7 GHz• Infrared

Modulation• Frequency shift keying• Spread spectrum

- Frequency hopping (FHSS)- Direct sequence (DSSS)


Wireless LAN Characteristics Speed

• 60 kbps - 10 Mbps

Range• 80 - 1000 feet

Interface• Ethernet• Token Ring


IEEE 802.11 “Standard” Adopted June 1997

Allows speeds up to 2 Mbps (10 Mbps soon)

Includes multiple PHY layers• Infrared• 2.4 GHz Direct sequence (DSSS)• 2.4 GHz Frequency hopping (FHSS)

University of New Hampshire doing interoperability testing• DSSS• FHSS

IEEE 802.11 product deliveries began in 1998


Wireless LAN Products Aironet

Breezecom

Digital Roamabout

Lucent - WaveLAN

Proxim RangeLAN2

Symbol Technologies - Spectrum 24


WaveLAN Market Share

Proxim15%

Aironet17%

Symbol9%

Breezecom4%

Other12%

Digital2%

Lucent Technologies

41%

Source: BRG Dec ‘97


Lucent WaveLAN II Frequency: 2.4 GHz

Modulation: DSSS

Speed: 2 -> 10 Mbps

Coverage: 50,000-500,000 sq ft

Interface: Ethernet (IEEE 802.3 or Token Ring (IEEE 802.5)


Lucent WaveLAN II WavePoint Access Point ($995)

• Bridging function• Mounts on wall• Ethernet interface• Token ring interface• Optional

WaveLAN Network Adapter ($295)• PCMCIA Type II


Wireless Andrew I Research network

• Covers seven buildings• 101 access points• More than 100 users• Lucent WaveLAN I equipment

- 915 MHz• Full operation Spring 1997


Wireless Andrew II Production network

• Will cover all academic and administrative buildings -- no residence halls

• About 400 access points• Available to all 10,000 students, faculty, staff• Lucent WaveLAN II equipment

- 2.4 GHz- IEEE 802.11

• Full operation late 1999


Wireless Andrew II Technical Issues

Coverage oriented access point layout• Complete coverage with minimal overlap• Changing environment• Interference sources

Capacity oriented access point layout• Enough capacity for expected usage• Consideration of high- and low-density areas• Use of threshold setting and frequency reuse


Issues for research Likely, customers will need to use one or more wireless networks• Several now, more future• Shakeout unlikely• Inherent tradeoffs in speed, distance, and

coverage- Wireless LANs- CDPD- RAM and ARDIS- Analog Cellular- LEOS


Most of the Layers of OSI Model Layer 2: Roaming (wireless LAN)

Layer 3,4: “Mobile IP” addressing and routing

Layer 6: Adaptive compression

Layer 7: Mobile-aware applications and

Distributed file systems


Research Projects• Transparent Networking Support for Mobile

Hosts: David Johnson• Wearable Computers: Dan Siewiorek• Image and Video Compression for Wireless

Links: Jose Moura• Handheld Andrew: Tracy Futhey


Wearable Computers Marines (Ft Pendleton): Technical inspections


AEG at Pittsburgh International Maintenance inspection and repair

copyright ©1998 alex hills 1 the “vision” of wireless access: anyone anything anytime anywhere...

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