120 likes | 234 Views
TIA Wireless Discussions. Jeffrey Schiffer 10/09/02. Topics. Wi-Fi Overview 802.11 Flavors (a, b, g, e, h…………..) Technical comparison Spectrum, “get me more!!!” Global Harmonization Deployment Barriers. PAN vs. WLAN. PAN “Private Data” Local to user Short range (10 meters)
E N D
TIA Wireless Discussions Jeffrey Schiffer 10/09/02
Topics • Wi-Fi Overview • 802.11 Flavors (a, b, g, e, h…………..) • Technical comparison • Spectrum, “get me more!!!” • Global Harmonization • Deployment • Barriers
PAN vs. WLAN • PAN • “Private Data” Local to user • Short range (10 meters) • Examples: Bluetooth, UWB • WLAN • “Public Data” External to user • Medium range (100 meters) • Access to external data sources • Examples: 802.11b, 802.11g, 802.11a
The 2.4 GHz Band • Services: • Bluetooth: PAN, 1 Mbps, Master/slave, piconet • 802.11b: WLAN, up to 11 Mbps, AP or Peer-to-Peer • Interferers: Microwave ovens, cordless phones, etc. • Worldwide: • Harmonized in ALL major geographies (both freq. & pwr)
The 5.x GHz Band • Services: • 802.11a: WLAN, up to 54 Mbps, AP based Peer-to-Peer optional • Hiperlan 1: WLAN, up to 23 Mbps, AP based • Worldwide: • NOT Harmonized. Different power levels for different frequency bands, different spreading requirements for different bands, different operating bands different countries Lack of Harmonization is a Barrier to Deployment
IEEE 802.11 Activities • 802.11a: PHY based on OFDM (Orthogonal Frequency Division Multiplexing) technology (5.x GHz) • 802.11b: Based on DSSS (Direct Sequence Spread Spectrum) technology (2.4 GHz) • 802.11g: Based on OFDM (Orthogonal Frequency Division Multiplexing) technology (2.4 GHz) [1H’03?]
802.11 Standards 802.11e Quality of Service 802.11h European regulatory extensions 802.11d International roaming 802.11a 5GH OFDM, 54Mbps 2001 2002 2003 1999 2000 802.11b 2.4GHz CCK, 11Mbps 802.11f Inter-access point protocols 802.11i Improved security 802.11c 802.11 Bridging tables 802.11g 2.4GHz CCK or OFDM, 54Mbps Standards: 802.11 All Lined Up
Task Groups • Task Groups working on 802.11 enhancements • TGe: QoS (Quality of Service). This is essential for future audio & video distribution. Greatly effected by TGi (content protection issues) • TGf: Inter access point protocol. Working to increase vendor interoperability (currently few features in AP work) • TGg: WLAN, up to 54 Mbps, AP or Peer-to-Peer • TGh: DFS (Dynamic Freq. Selection) & TPC (Transmit Power Control) enhancements to 802.11a. Focused on adding features to meet other country requirements. Necessary for products to operate in Europe • TGi: Security. New focus on: TKIP (Temporal Key Integrity Protocol), AES (Block cipher to replace WEP and RC4), 802.1x (authentication method, a standard for controlled port access)
Spectrum Issues • Current policy is based on ’30’s technology, single user little local reuse • ISM spectrum is shared between many services, (bands are VERY crowded), different access methods might be required for efficient frequency reuse. • Different regulations for “indoors vs. outdoors” use, NOT practical with today’s mobile clients • Harmonization, regulators need to shift from parochial view to global perspective (when I travel I do not want to operate illegally, 5 GHz issue)
Spectrum Issues cont’d • More spectrum driven from harmonization perspective. Additional band under discussion 5.47 – 5.725 GHz • High-Tech, including Intel and MS, are advocating more spectrum at 5 GHz (ala WECA petition). • We also support the FCC imposed etiquette at 5 GHz, ( TPC and DFS). The EU requires them already and getting additional spectrum from DOD in U.S. will require DFS. • A concern at this point is that the FCC technical requirements beyond TPC and DFS are not defined.
Deployment Issues • Global spectrum harmonization – What does the user do? Forces manufacturers to create many “skews” of product • Universal billing method – Roaming model similar to cell phones • Roaming between systems/services – Switching from WLAN to telecommunications infrastructure, etc. • Ease of use – connection establishment, hand-off, security, etc. • User education – Capabilities of systems, network options, system operation • SAR (Specific Absorption Rate) health/safety testing issues. This effects multiple solutions in a single system