university of washingtoncomputing & communications wireless networking terry gray, scott mah,...

University of Washington Computing & Communications

WIRELESS NETWORKING

Terry Gray, Scott Mah, David Richardson, Marc Hudson

UW Computing & Communications

January 2002


Agenda

• Background

• Objectives

• Policy Issues

• Technology Issues

• Deployment Status

• Pricing and Process

• Conclusions


Wireless Categories

• Wireless by Purpose– Point-to-Point links– Access networks

• Wireless by Spectrum– Optical– Infrared– RF

• Wireless by Range...


Wireless RF by Range• PAN/HAN (Personal/Home-Area-Network)

– Bluetooth– HomeRF

• LAN (Local-Area-Network)– IEEE 802.11 (US)– ETSI HiperLAN2 (Europe)

• 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

• IEEE 802.11e QoS, etc

• IEEE 802.11g 2.4GHz, 20+Mbps

• In US, all use unlicensed “ISM” bands


802.11a: Successor?

• Faster• Shorter distance• More power consumption• Available this year, but...• Won’t replace 802.11b too soon• Probably need WAPs for both, or dual-

mode WAPs


C&C Wireless Objectives

• Provide 11 Mb coverage throughout selected facilities

• Allow roaming within facility space

• Deploy scalable and manageable approach

• Provide high-availability service, fully integrated with campus wired net

• Balance between secure and convenient


Policy Issues• Part of campus network infrastructure

• DIY is OK if it doesn’t interfere… but less convenient for users

• Want to allow temp or small-scale ad hoc deployments with minimum overhead

• Large-scale deployments need to be coordinated with C&C

• Campus-wide access control policy

• Security/abuse liability


Technical Issues• Infrastructure & Topology• Roaming• Access control & Security• Interoperability & Obsolescence• QoS• Interference• Relationship to Bluetooth, etc• Manageability


Wired vs. Wireless Issues

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


Infrastructure Requirements

Phones Wired Wireless

Closets YES YES YESConduit YES YES YESWireplant YES YES Much

Switches Maybe YES Much

WAPs NO NO YES

Power Maybe YES ClosetsOnly*

* For C&C deployments –using DC power injectors


Roaming

• 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.


Current Access Control Policy

• Goals:– avoid embarrassment of drive-by hackers doing

bad things via UW network– avoid numerous problems with getting

windows login to work thru firewalls• Implementation:

– Auth required only for off-campus access– All UWnetID holders are authorized– Roaming between buildings not supported


Access Control Deployment• Using a commercial product from Vernier• Provides access control for "downstream"

networks (wired or wireless)• Supports L3 roaming, transparent to client• Uses NAT• No special s/w required on client machines• Intercepts port 80 requests• Incorporates UW pubcookie authentication• MAC-address-based security


Access Control Futures

• Need to look at performance issues closely

• Evaluating feasibility of adding pubcookie authentication to C&C Logical Firewall


Operational Challenges

• Performance monitoring

• Performance problem diagnosis

• Capacity planning

• QoS

• Abuse tracking


Current Deployments

• C&C Pilot Project– Kane Hall, Rm. 130– Mary Gates Hall– Gerberding Hall– Odegaard Undergraduate Library

• Other wireless projects– CS&E, C&C, Business, Law, MCIS, ...


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


How much does it cost?

• Wireless survey

• Facilities pathways, electrical, and asbestos abatement

• New subnet for wireless access points

• Installation of wireless access points

• Ongoing operations, maintenance, and security for wireless access points


Monthly Rates

• $75 per month per access point

• $500 installation per access point

If equipment and project is funded through one-time capital dollars, then the monthly rate for operations and maintenance is:

• $35 per month per access point


Ordering Wireless Solutions

• Wireless networking Web site www.washington.edu/computing/wireless/• Initiate request by email to

[email protected]• Call 206-543-5068• Project assigned to a Customer Account

Manager to coordinate activities within C&C and contractors


Conclusions

• Wireless is very addictive.

• It will be very popular.

• It will be very problematic.

• It will cost more than you expect

• In offices, it is not a replacement for wired.

• The dust has not settled.


References• 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)• Wireless Data Forum• http://www.80211-planet.com/• http://www.wireless-nets.com/guide.htm• http://www.practicallynetworked.com/

university of washingtoncomputing & communications wireless networking terry gray, scott mah,...

Documents

convenient slide

manageability slide

network ieee

mbps ieee

dual mode waps slide

uw network

dsss ieee

fixed wireless wan widearea