80211 the end of wireles or is it

802.11n: The End of Wires? Or is it?

Wireless LAN Trends

Preparing for 802.11n

Research

• InformationWeek Analytics survey & paper published Dec, 2009

• 779 tech pros responded

• A peek into what IT is thinking when it comes to wireless networks

Main Research Goals

• Discover if, and when, wireless might replace wired networks

• Examine preferences in architectures

• Explore issues relating to regulatory compliance and security

• Determine if 802.11n ratification has influenced IT’s plans

Device Trends

• Growing mobile & portable percentages:

– Smartphones

– Netbooks

– iPads and iPad-like devices

– Tablets

• Fewer PC & Workstation purchases

Growing mobility is pushing the adoption of better, faster wireless

Source: Nothing but Air: Why 802.11n Will Revolutionize Connectivity. InformationWeek Analytics, 12/2009

Main WLAN Worries

• We’re buying mobile devices but are worried about the network to which they connect!

– Reliability—53% “It’s gotta work all the time”

– Performance—50% “It’s not fast enough”

– Data Security—48% “I don’t trust it”

– Consistency—41% “Same experience always”

• Other: Cost, Maturity, “It’s different”

• 11% think it’s good to go now!



Standards & Specifications

• IEEE defines technology through standards

• Wi-Fi Alliance publishes specs based on the standard to aid vendor interoperability

– 802.11a/b/g & “CERTIFIED n”

– WMM, WPA/WPA2

– And others

• Spells out a device’s capabilities

• Helps you understand what you’re buying

Decentralized

• Autonomous AP

• Each forwards data onto or off of wired net

• Essentially dumb individual APs

Fully Centralized

• Controller/Light AP

• Controller is “the brain” and forwards, firewalls, does QoS

• APs are aware of each other for roaming, channel assignment.

• Controller is the bottleneck!

Hybrid/Modern Decentralized

• Controller

• Or no controller

• Smarter APs can forward, firewall, QoS

• Or controller does it

• APs are aware of each other for roaming, channel assignment.

• Smarter edge alleviates the bottleneck. Key for 802.11n!

Architecture Evolution

WLAN Security

• WLAN security is a big concern but numerous 802.11i-based WPA2 approaches are indeed highly secure.

• Encryption—Data privacy – WEP (bad, very bad)

– WPA (“auto WEP”) / WPA2 (AES strong crypto)

• Authentication—Who are you?– Pre-shared keys or…

– 802.1X/EAP strong authentication

• Firewall policy—Dictates what you can touch

• WLAN intrusion detection & prevention

Regulatory Compliance

• Do These:

– Maintain a written WLAN policy governing use

– Use strong encryption & authentication

– Firewall nodes processing or containing sensitive data

– Monitor unauthorized use

– Log general use

• Good Practice Includes:

– Know who’s using

– Make sure it’s them

– Maintain confidentiality

• Regulations:

– PCI DSS

– HIPAA & HITECH

– Sarbanes-Oxley

– And more


Key 802.11n Features

• ~5x throughput & ~2x the range than before. 300 Mbps with more to come

• More efficient transmission

– Uses UNII or ISM bands & 20 or 40 mhz channels

– Frame aggregation & guard interval tweaks

• MIMO signaling

– Multipath is now our friend

– Multiple simultaneous data streams

Top Considerations: Application

• Thoroughly analyze the applications that are driving the need for Wi-Fi

– Latency & QoS

– Signal strength & Throughput

• Design accordingly

– VoWiFi requires clean, strong signals

– Employee LANs vary by apps riding them

– Guest networking is far more forgiving

Green means OK for VoWiFi

Same Floorplan…Green means OK for General

Data Networking

Top Considerations: Architecture

• Avoid wired-side bottlenecks prevalent at high rates

• Avoid single points of failure

• Can your older 802.3af PoE switches power the new gear? Or is 802.3at required?

• What are the coverage and capacity requirements?

• Consider reserving the 5 Ghz UNII bands for n-only and the 2.4 Ghz ISM bands for legacy b/g/a + n

Top Considerations: Environment

• Construction materials…

– affect signal strength which affects…

– cell sizes which in turn affects…

– data throughput at different points in the coverage area

• LOS was best for b/g/a. Multipath best for n.

• Consider investing in good site survey planning tools & WLAN troubleshooting tools

Top Considerations: Security

• Design to be as secure as resources will allow

• Understand the available security options and their impact on the network. Ex: RADIUS

• Define the authentication and encryption schemes

• Understand regulatory compliance requirements

• Work the WLAN into your security policy framework

• Understand reporting requirements

Top Considerations: Client devices

• Understand client-side capabilities to avoid a Porsche network accessed by Edsel laptops.

• When looking at your current equipment…

– Are they “n” capable?

– What type of MIMO do they support?

– How old are the drivers?

– Do the supplicants support the 802.1X/EAP authentication types you plan to use?

Top Considerations: Product Choice

• When shopping for gear, Caveat Emptor

• Do your product research. See what others are saying.

• Get to know WLANs if you don’t already.

• Wrap your head around new terms such as…

– spatial multiplexing

– channel bonding

– frame aggregation

– beamforming

Top Considerations: Management

• Consider how you will manage the gear

• Will it be a self-contained system or will it integrate with another management platform?

• How will you get alerts out of the system?

• Who in the organization will manage it and be the wireless specialist(s)?

Top Considerations: Education

• Start with vendor-neutral Wi-Fi education. CWNP is a great start.

• Understand your organization’s wireless mission. How will it be used and for what?

• Study up on your vendors’ design guides

• Next hit the vendor-specific training

• Have a test lab if possible

Future WLAN Publications

• Here’ what we’re thinking…

– Best Practices: WLAN Management. Ten Mistakes to Avoid

– Research: Wireless Nation 2011. 4G vs. Wi-Fi

– Strategy: Voice over Wi-Fi

• Please email us ideas: [email protected]