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CAMPUS NETWORK DESIGN: Wired vs. Wireless. Terry Gray Director, Networks & Distributed Computing UW Computing & Communications September 2001. Scope of UW Networking. UW Campus Networks Seattle Tacoma Bothell/CCC Medical Centers (net design) UW Physicians Network UW Medical Center
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CAMPUS NETWORK DESIGN:Wired vs. Wireless Terry Gray Director, Networks & Distributed Computing UW Computing & Communications September 2001
Scope of UW Networking • UW Campus Networks • Seattle • Tacoma • Bothell/CCC • Medical Centers (net design) • UW Physicians Network • UW Medical Center • Harborview Medical Center • Pacific/NorthWest Gigapop • Pacific Wave exchange point • Pacific Light Rail • Statewide K20 Network
Baseline Connectivity • Shared 10Mbps HD • Switched 10Mbps HD • Switched 10/100Mbps FD • backed by GE switch/router infrastructure • Goal: Switched 10/100 FD for all; GE for a few • Reality: Cat3 wireplant upgrade will take multiple years and multiple millions of dollars
Advanced Services • Multicast • Partially deployed • Older routers need to be replaced • QoS • Laissez faire? Premium service? • Best with FD connections. • VoIP • Needs QoS, extra-high availability • POE desirable; implies UPS in closets • IPv6
Premium Services? • Wide-area QoS chargeback? • Preferred access to Internet for a fee? • Lots of interesting policy and tech issues...
Mistakes We Didn't Make • FDDI to the desk • VLANs • ATM • Various "cut-thru IP switching" digressions • Claim: Staying with pure IP and Ethernet has served UW very well...
Current Statistics • Avg Backbone traffic: nearly 2 TB/day • Peak Inbound traffic: 100 Mbps (40 in 1999) • Peak Outbound traffic: 160 Mbps (20 in 1999) • Doubling time: Less than 2 years!! • Hosts: over 50,000 • Modems: over 2,000 • Switched subnets: 70% (30% in 1999) • 10/100 FD subnets: 25% (5% in 1999) • Cat 5 buildings: 10%
Physics/Astronomy Fisheries Center new Ocean Lander Hall McCarty Hall Parrington Hall Edmondson Pavillion Mary Gates Hall OUG Library part of Electrical Engr. part of HS K wing part of HS T wing part of Johnson Hall part of Savery part of Thomson Hall part of 4545 GigE Buildings
Simplified Network Topology Core Switch Gigapop 4 Fed Nets Border Router Internet2 Router Router 30 Internet Interior Switch Interior Switch 300 PBX Edge Switch Edge Switch 1000+ Branch Site 50,000 Desktop Desktop
Recurring Theme: Explosive Growth • More users • More devices • Longer use • New (bandwidth-intensive) applications • e.g. remote collaboration tools • audio/video streaming • tele-immersion • distance learning
Networking Hot List • Campus building/subnet upgrades • Backbone upgrades (production, experimental) • Regional networking • Network Hardening • Security • Advanced Services • Wireless • Management/diagnostic tools
Success Metrics • 10/100 FD connections: xx% • Multicast deployment: xx% • QoS deployment: xx% • Dept’l wireless coverage: xx% • Router center hardening: xx% • Backbone capacity • IPv6 capable routers
Wireless Categories • Wireless by Purpose • Point-to-Point links • Access networks • Wireless by Spectrum • Infrared • RF • Optical
Wireless RF by Range • PAN/HAN (Personal/Home-Area-Network) • Bluetooth • HomeRF • LAN (Local-Area-Network) • IEEE 802.11 • ETSI HiperLAN2 • MAN (Metro-Area-Network) • LMDS, “Fixed Wireless” • WAN (Wide-Area-Network) • Ricochet (R.I.P.) • CDPD • 2.5G, 3G, etc, etc, etc
LAN Wireless Standards • IEEE 802.11 2.4GHz, 1-2Mbps, FHSS, DSSS • IEEE 802.11b 2.4Ghz, 11Mbps DSSS (WiFi) • IEEE 802.11a 5Ghz, 54Mbps • ETSI HiperLAN2 5Ghz, 54Mbps, TDMA • In US, all use unlicensed “ISM” bands
802.11 ISSUES • Network Design, esp. Topology • Access control • Security • Compatibility • Interference • Relation to Bluetooth, HomeRF, etc • Obsolescence
ROAMING ISSUES • Layer 2 (802.11) vs. Layer 3 (Mobile IP) • Vendor incompatibility • LAN vs. WAN • We will support L2 roaming within a building by dedicating one subnet for all access points in the building.
Policy Issues • Part of campus network infrastructure • Want to encourage small-scale deployments with minimum overhead, but coordination needed to avoid interference • Large-scale deployments need to be coordinated by C&C • Campus-wide access control policy
UW-S Wireless Deployment • C&C Pilot Project • Kane Hall, Rm. 130 • Mary Gates Hall • Gerberding Hall • Odegaard Undergraduate Library • Other wireless projects • CS, C&C, Business, MCIS, ...
Pilot Project Objectives • Provide 11 Mb coverage throughout selected facilities. • Allow roaming within facility space. • Develop suitable policies. • Gain operational experience.
Pilot Project Lessons Learned • Success depends on cooperation w/dep’ts • It takes more wire than you think! • Site surveys & frequency sweeps needed. • WEP is not secure; use SSH, SSL, etc. • Technology still evolving • 2.4GHz phones interfere badly
Wired vs. Wireless Issues • Server suitability • Performance • Performance variation • Price/Performance • Interference • Technology maturity • Advanced services • Security
802.11a: Successor? • Faster • Shorter distance • More power consumption • Probably won’t replace 802.11b • Probably need WAPs for both
Conclusions • Wireless is very addictive. • It will be very popular. • It will be very problematic. • The dust has not settled. • In offices, it is not a replacement for wired. • In classrooms, lounges, etc, it is… but that still requires some wired infrastructure.
Wireless References • Open Group: www.openwirelessdata.org • Wireless Ethernet Compatibility Alliance (WECA) • Wireless LAN Association (WLANA) • Portable Computer & Communications Association (PCCA) • Internet Engineering Task Force (IETF) • WAP Forum • Bluetooth Special Interest Group • Mobile Wireless Internet Forum (MWIF) • Wireless Information Networks Forum (WINForum) • HiperLAN2 Global Forum • Wireless Data Forum