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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.
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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