CAMPUS NETWORK DESIGN: Wired vs. Wireless

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CAMPUS NETWORK DESIGNWired vs. Wireless

• Terry Gray
• Director,
• Networks Distributed Computing
• UW Computing Communications
• September 2001

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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

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Pacific Northwest Gigapop
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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

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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

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Premium Services?

• Wide-area QoS chargeback?
• Preferred access to Internet for a fee?
• Lots of interesting policy and tech issues...

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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...

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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

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UW-S Building/Subnet Status
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GigE Buildings

• 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

• Physics/Astronomy
• Fisheries Center
• new Ocean
• Lander Hall
• McCarty Hall
• Parrington Hall
• Edmondson Pavillion
• Mary Gates Hall
• OUG Library

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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
12

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Number of Devices
14
Backbone Traffic
15
Border Traffic 1999
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Border Traffic 2001
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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

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Networking Hot List

• Campus building/subnet upgrades
• Backbone upgrades (production, experimental)
• Regional networking
• Network Hardening
• Security
• Advanced Services
• Wireless
• Management/diagnostic tools

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Success Metrics

• 10/100 FD connections xx
• Multicast deployment xx
• QoS deployment xx
• Deptl wireless coverage xx
• Router center hardening xx
• Backbone capacity
• IPv6 capable routers

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On to Wireless...
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Wireless Categories

• Wireless by Purpose
• Point-to-Point links
• Access networks
• Wireless by Spectrum
• Infrared
• RF
• Optical

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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

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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

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802.11 ISSUES

• Network Design, esp. Topology
• Access control
• Security
• Compatibility
• Interference
• Relation to Bluetooth, HomeRF, etc
• Obsolescence

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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.

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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
  CC
• Campus-wide access control policy

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UW-S Wireless Deployment

• CC Pilot Project
• Kane Hall, Rm. 130
• Mary Gates Hall
• Gerberding Hall
• Odegaard Undergraduate Library
• Other wireless projects
• CS, CC, Business, MCIS, ...

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Pilot Project Objectives

• Provide 11 Mb coverage throughout selected
  facilities.
• Allow roaming within facility space.
• Develop suitable policies.
• Gain operational experience.

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Pilot Project Lessons Learned

• Success depends on cooperation w/depts
• 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

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Wired vs. Wireless Issues

• Server suitability
• Performance
• Performance variation
• Price/Performance
• Interference
• Technology maturity
• Advanced services
• Security

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802.11a Successor?

• Faster
• Shorter distance
• More power consumption
• Probably wont replace 802.11b
• Probably need WAPs for both

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Infrastructure Requirements
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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.

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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