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This backgrounder by Terry Gray and Scott Mah outlines critical policy discussions surrounding wireless technology in academic environments. Addressing technology, funding, and bandwidth issues, it emphasizes the challenges of integrating wireless solutions with existing campus infrastructure. Topics include central versus departmental wireless management, security policies, and the implications of rapid technological changes. The document highlights the necessity for consistent standards and funding models to ensure sustainable and secure wireless access for users across the campus.
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Backgrounder for Policy Discussions on Wireless Terry Gray Director, Networks & Distributed Computing Scott Mah Director, Communication Technologies February 2004
Outline • Generalities • Technology Issues • Policy Issues • Funding Issues • Bandwidth Issues
Wireless is... • Addictive (users love it) • Seductive (appears to be cheaper/easier than it is) • Expensive to scale to an enterprise-class solution • Encouraging enclaves, balkanization • Rapidly changing technology • Hard to control • Hard to secure • Either parasitic upon, or synergistic with, overall campus network infrastructure • Best seen as needing to parallel history of deployment of Internet at the UW • Becoming mission-critical
Key Issues • Central vs Departmental wifi coexistence • Technical standards • Unauthorized access points • Security policies (protecting others) • Access control policies (who can use?) • Funding and accounting policies • Rented space, student-owned equipment
Technology Issues • Standards • IEEE 802.11a, b, e, f, g, h, i (and more!) • IEEE 802.1x, LEAP, PEAP, TLS, TTLS • Monitoring, management • RF propagation, interference, pwr mgt • Security, access control • Performance, QoS • Availability, Reliability • Convergence
Impact of VOIP over Wireless • Separate backbone? • Campus-wide roaming? • Quality/Reliability expectations?
Policy Issues • Access control • Departmental/private nodes • Who, if not C&C under U-TAC policy direction, owns/controls RF spectrum? • Who defines standards and minimum security and coexistence policies? • Who enforces standards & minimum security and coexistence policies? • How will an extensible, scalable and sustainable model be established
Central vs. Departmental Tensions • C&C not out front (we’d say not able to be :-) • Inconsistent access policies (private enclaves) • Inconsistent or non-existent security provisions • Inconsistent or incompatible technology • Inconsistent upgrade & maintenance policies • 24-7 management • Integration with central network infrastructure • Integration with central authentication infrastructure • Risks to central net infrastructure and nearby hosts
Private Wireless Nodes on the Campus Net • Rationale: • Central service not available • Central wireless service too expensive (can plug cheap wireless access point into campus net) • Central service sometimes more inconvenient for visitors • Central service is an attractive nuisance • Very special research requirements • Special security requirements
Funding Issues • Central, departmental, subscription (voluntary or mandatory), STF... • One-time ‘Capital’ always easier to find than operating $$ • Recharge strategies incent rogue systems • Dealing with rogue access points dramatically increases operational costs and security dangers/costs • Department & STF deployments drive costs they don’t pay (‘coping and cleanup is an unfunded mandate’)
Cost Factors • Degree of convergence • wired and/vs. wifi data vs. wifi telephony • Security & access control • Technology immaturity, churn • Management & accounting features (exact parallel to routers and e-net switches etc, but harder!) • User support • Scaling (+ and - economies of scale) • Sustainability
Essential Capital Cost Elements • Physical facilities (e.g. power, cooling, pathways, equipment space and antenna space) • Wireless Access Points (WAPs) • Dedicated subnets for wireless (wired Ethernets to WAPs, switches, routers, security boxes, etc.) • Access point management system • Authentication system • Authentication management system
Operational Cost Elements • UW Staff • Design • HW Installation and SW Configuration/updating • Monitoring and reporting • Troubleshooting • Security incident handling (harder w/wireless) • User Support • Sustaining underlying ‘wired’ net. infrastructure • Vendor • Maintenance & Upgrades (firmware, SW and HW)
Case Study: MGH (a new and very well wired facility) • Size: 99,000 ASF • Classrooms: 27 + 12 • Floors: 4 • Access Points: 36 • Initial Cost: $94,000 • Initial Cost per Classroom: $2,500
Bandwidth Consequences • Wireless implies many more computers, PDAs, hybrid cell/802.11 devices, etc. • Steady growth (or maybe even spike, esp. with ‘net generation’ students) in network devices • Bandwidth needs track: • users • usage • apps and objects • capacity • Wireless capacity constrains types of apps (for now)
Performance Comparison [fromearly 2002;Gig Ethernet can now exceed 900 Mbps ] From www.extremetech.com
Network Device Growth Note: Most dips reflect lower summer use; last one is a measurement anomaly
Outcomes to Avoid • Unrealistic security expectations • Department wireless deployments that... • Confuse users re: who supports what • Interfere with or destabilize campus network • Create extra threats to others • Balkanize net services w/conflicting policies • Drive U-wide costs no one is underwriting • Non-scalable or non-sustainable models