Wireless Networks

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1 Wireless Networks Presentation for North Central Regional Meeting October 19, 2010 Tom Jones, PE, RCDD / NTS Field Sales Engineer, D-Link

2 Agenda Brief History of Wireless Networks b, g a New Features of n Wireless Site Surveys Wireless Design Legacy, Mixed, and Greenfield Modes PoE and Wireless Access Points Managing the Wireless Network

3 WLAN Brief History Late 1980s - High Cost, Proprietary 900MHz Systems, 860 Kbps Data Rate, Reliability Low IEEE Begins Draft of Spec July Released, 900MHz or 2.4GHz September b Ratified, Covers Only DSSS; Reliable IMS Band, 2.4GHz, 11 Mbps - Now a Reasonable Priced Product a Also Ratified for 54Mb In 5GHz Band, but No Products Available

4 WLAN Brief History a Chipsets & Products Become Available g Draft Spec, Similar il to b, but Higher Data Rates (54Mb) i Draft Spec, Stronger Encryption for Wireless Networks g Ratified in June i Ratified in June n Draft Spec Proposed for Higher Speed n Draft 2.0 Released Wi-Fi.org Began Certifying n Draft Virgin America Launches In-Flight Wi-Fi n Ratified in October

5 Wireless LAN Choices 900MHz vs. 2.4GHz vs. 5GHz 900 MHz ISM 2.4 GHz ISM 5 GHz U-NII PROs IEEE Global l Market Global l Market? Greater Range Than 2.4GHz for Internal LANs IEEE b, g IEEE a Higher Data Rates Higher Data Rates (11-54 Mbps) (22-54 Mbps) 8 Channels CONs Maximum Data Rate of 1 Mbps Limited Bandwidth Crowded Band Less Range Than 900MHz for Internal LANs Only 3 Channels Less Range Than 900MHz or 2.4GHz Higher Cost RF Components Larger Antenna ISM - Industrial, Scientific, & Medical Band U-NII - Unlicensed National Information Infrastructure Band

6 IEEE Task Groups a - 5 GHz, 54 Mbps (1999/2001) b GHz, 11 Mbps (1999) c - MAC Layer Bridging (Now in 802.1d) d - Extending in Other Countries (2001) e - Wireless QoS & Packet Bursting (2005) f - Roaming and Inter-Vendor Access, Inter-Access Point Protocol (2003) (withdrawn 2005) g GHz, 54 Mbps (2003) h - Adapt a for Europe Standards, d Dynamic Frequency Selection (DFS) and Transmit Power Control (TPC) (2004) i - Enhance Security (*formerly part of e) (2004) j GHz Band for Japan (2004) k - WLAN Radio Resource Measurement m - Maintenance to Correct Editorial i and Technical Issues of n - Proposed (goal: fall 2008) 2.4 GHz and 5GHz, 100Mbps or better p - Support for mobile (<200 kph) 5 GHz connections up to 1 kilometer r - Fast roaming support for real-time applications such as VoIP s - Protocol for auto-configuring paths between APs for multicast, ESS Mesh Networking t - Performance metrics, measurement methodologies and test conditions u - Amend MAC & PHY to support interworking with external networks v - Wireless Network Management enhancements w - Protected Management Frames y - Contention Based Protocol

7 Agenda Brief History of Wireless Networks b, g a New Features of n Wireless Site Surveys Wireless Design Legacy, Mixed, and Greenfield Modes PoE and Wireless Access Points Managing the Wireless Network

Channels in USA Use 1, 6, 11 for 3 Non-overlapping Channels Frequency

8 802.11b/g In the 2.4GHz Band b or b/g Most Common For Almost a Decade FCC Allocated 11 Channels in USA Use 1, 6, 11 for 3 Non-overlapping Channels Frequency enc Band Crowded with Other Apps Bluetooth Cordless Home Phones & Stereo Earphones Wireless Mice & Keyboards Microwave Ovens

9 802.11b/g Throughput g Performance Decreases When b Devices Enter Network Data Rate (Mbps) Approximate Max Throughput (Mbps) b g (802.11b clients in cell) g (no.11b clients in cell)

10 Agenda Brief History of Wireless Networks b, g a New Features of n Wireless Site Surveys Wireless Design Legacy, Mixed, and Greenfield Modes PoE and Wireless Access Points Managing the Wireless Network

11 802.11a In the 5 GHz Band Devices Took Longer to Get to Market Faster Speed than 11b, but Less Range More Channels and No Overlap Issues Less Congestion From Other Applications FCC Keeps Changing g Allowed Channels Data Rate (Mbps) Approximate Max Throughput (Mbps) a 54 25

12 channel frequency (MHz) United States Europe Japan Singapore China Israel Korea Turkey 40/20 MHz 40/20 MHz 40/20 MHz 10 MHz 20 MHz 20 MHz 20 MHz 20 MHz 20 MHz No No No Yes No No No No No No No Yes Yes No No No No No No No No Yes No No No No No No No No Yes No No No No No No No Yes Yes No No No No No No No No Yes No No No No No No No Yes No No No No No No No No Yes No No No No No No No No No Yes No No No No No No No No Yes No No No No No No No No Yes No No No No No No No No Yes No No No No No No No No No No No No No No No No No No No No No No No No No No No No No Yes Yes Yes Yes Yes Yes No Yes No Yes Yes Yes No No No No No No Yes Yes Yes Yes Yes Yes No Yes No Yes Yes Yes No No No No No No Yes Yes Yes Yes Yes Yes No Yes No Yes Yes Yes No No No No No No Yes Yes Yes Yes Yes Yes No No No Yes Yes Yes Yes Yes Yes No No No Yes Yes Yes Yes Yes Yes No No No Yes Yes Yes Yes Yes Yes No No No Yes Yes Yes Yes Yes Yes No No No Yes Yes Yes Yes Yes Yes No No No No Yes No Yes Yes Yes No No No No Yes No Yes Yes Yes No No No No Yes No Yes Yes Yes No No No No Yes No Yes Yes Yes No No No No Yes No No Yes Yes No No No No Yes No No Yes Yes No No No No Yes No No Yes Yes No No No No Yes No No Yes Yes No No No No No No Yes Yes Yes No No No No No No Yes Yes Yes No No No No No No Yes No No No Yes Yes No Yes Yes Yes No No No Yes Yes No Yes Yes Yes No No No Yes Yes No Yes Yes Yes No No No Yes Yes No Yes Yes Yes No No No Yes Yes No Yes Yes

13 Agenda Brief History of Wireless Networks b, g a New Features of n Wireless Site Surveys Wireless Design Legacy, Mixed, and Greenfield Modes PoE and Wireless Access Points Managing the Wireless Network

14 New in n Standard MIMO 2, 3, or 4 Simultaneous Spatial Streams Maximal Ratio Combining (MRC) Antenna Diversity for MIMO Channel Usage and Channel Bonding 20 MHz channel with 52/56 vs. 48/52 sub-carriers 40 MHz channel with 108/114 sub-carriers Reduced Guard Interval 400 nanosecond vs. 800 nanosecond Transmit Beamforming Smart antenna technology to aim MIMO effect Frame Aggregation Block Acknowledgements (ACKS)

15 802.11n Certification Wi-Fi Alliance Announced Phased-in Approval of Pre-standard n Products Certification Based on Draft 2.0 Started In Summer of 2007 Certification Based on Final Standard Began In Early 2010 Vendor products certified n Draft 2.0 will interoperate with the new Wi-Fi CERTIFIED n products in the same frequency band, even if they use different features

16 Agenda Brief History of Wireless Networks b, g a New Features of n Legacy, Mixed, and Greenfield Modes Wireless Site Surveys Wireless Design PoE and Wireless Access Points Managing the Wireless Network

17 Wireless Network Modes Legacy Mode APs are n capable, but no n clients yet n APs could give slightly better throughput Mixed Mode Mixed environment of a/b/g/n clients May provide some improvement for a/b/g clients, but n clients will not see maximum potential Greenfield Mode No legacy support for a/b/g clients Best throughput for n clients

18 Agenda Brief History of Wireless Networks b, g a New Features of n Legacy, Mixed, and Greenfield Modes Wireless Site Surveys Wireless Design PoE and Wireless Access Points Managing the Wireless Network

19 Site Survey For Any Wireless Network Design, a Site Survey Is the Only Way to Insure Coverage In All Desired Areas Proper Site Survey Includes Spectrum Analysis and Detailed Report Cannot Be Done Without Proper Tools Site Surveys Must be Done Specifically for the Type of Access Points and Client Devices a b/g n Not a Site Survey if Not Done Properly

20 Agenda Brief History of Wireless Networks b, g a New Features of n Legacy, Mixed, and Greenfield Modes Wireless Site Surveys Wireless Design PoE and Wireless Access Points Managing the Wireless Network

21 Wireless Design Site Survey Is First Step In Good Design Design Must Be Tailored to Wireless Mode Legacy, Mixed, or Greenfield Design Must Be Tailored to Wireless Type(s) a/b/g/n Just Replacing old APs with n APs Is Not a Good Design and Will Not Likely Give Best Coverage n AP Should Be Connected to Gigabit Ethernet Switch

22 Wireless Design Factors to Consider Should Include: Speed / Throughput Requirements Consider Applications to be Used Consider Expected Number of Users Future Requirements Security Requirements Aesthetic Considerations Environmental Considerations Indoor or Outdoor Plenum Rated or Plastic Case AP Mode or WDS Mode or Both

23 Thick or Thin Access Points Standalone or Thick APs Individually Configured Roaming Client Must Re-Associate to Next AP Cost Effective for Small Number of APs Managed or Thin Aps Wireless Controller Manages AP Configurations Standalone Controller or Built Into a Switch Seamless Roaming for Client Client Associates with Controller, not AP More oeexpensive einitial ta Cost

24 Agenda Brief History of Wireless Networks b, g a New Features of n Legacy, Mixed, and Greenfield Modes Wireless Site Surveys Wireless Design PoE and Wireless Access Points Managing the Wireless Network

25 Power Over Ethernet 802.3af PoE Standard Provides 48v DC Power Up To 15.4w at the Source Source can be the switch itself or a mid-span power injector Standard maximum power draw at device: 12.95w Be Careful to Look at Overall PoE Power Budget for the Switch Most switches do not provide enough power for full 15.4w on all ports New 802.3at PoE Plus Standard for 25w at the Source

26 Agenda Brief History of Wireless Networks b, g a New Features of n Legacy, Mixed, and Greenfield Modes Wireless Site Surveys Wireless Design PoE and Wireless Access Points Managing the Wireless Network

27 Managing the Wireless Network Two Basic Categories of Access Points Thick AP is standalone and each must be configured Thin AP is pass-through device and configuration is done on a controller that manages multiple APs Some APs can function either way Management Software Can Help with Thick Access Points May support automated firmware upgrade or configuration changes Some third party software packages support products from multiple l vendors

28 Fully Managed Wireless Network System with Controller(s) and Thin APs Controller May be Separate Box or Built Into a Switch Can Provide Many More Features Automatic channel selection Automatic transmit power settings Fast Roaming capability Captive Portal feature Visual Heat Map Rouge detection and mitigation Wireless Intrusion Detection System (WIDS) Note: WIDS for n must support both 20 MHz and 40 MHz channels

29 For More Details This Presentation Was Intended to Only Provide a High Level View of Wireless LAN Features Much More Detail Available in BICSI Wireless Design Reference Manual

30 Questions? Tom Jones, PE, RCDD / NTS Field Sales Engineer, D-Link Tom.Jones@dlink.com

Wireless Terms. Uses a Chipping Sequence to Provide Reliable Higher Speed Data Communications Than FHSS

Wireless Terms. Uses a Chipping Sequence to Provide Reliable Higher Speed Data Communications Than FHSS How to Set Up a Secure Home Wireless Network What you don t know about setting up a home wireless network can hurt you. 2008 APCUG Convention Session Tom Jones, P.E., RCDD-NTS CQS-CWLSS AGENDA Some Terms