Wireless Protocols You Just Have to Know About!

Todd Lammle (FCC RF Licensed)

Certified Wireless Administrator (CWA) instructor, Sybex author

www.wirelesstechnologygroup.org

www.globalnettraining.com www.routersim.com

About Todd Lammle

President, GlobalNet Training, inc CEO, RouterSim, LLC Sybex author

Objectives

To understand the term “WLAN” To understand the current IEEE wireless

standards To understand the future IEEE wireless

standards To gather information that will allow you to

make informed decisions

Why do we care?

Can I just use it till I need glasses?

P lease Mr. IT guy, don't take my Wireless!

Wireless Is Addicting

Once You Use It

You Can’t Live without ItYou Can’t Live without It

What’s a typical “LAN”?

What’s a typical WLAN?

It’s a “hub” without wires

Wireless LANS (WLANs) use “Cells”

Channel Overlap to cover distance

Audio

AM Broadcast

Short-Wave Radio FM Broadcast

TelevisionInfrared Wireless LAN

Cellular (840MHz)

NPCS (1.9GHz)

ExtremelyLow

VeryLow

Low Medium High VeryHigh

UltraHigh

SuperHigh

Infrared VisibleLight

Ultra-violet

X-Rays

ISM Unlicensed Frequency Bands

902–928 MHz26 MHz

902–928 MHz26 MHz

5 GHz(IEEE 802.11)

HyperLANHyperLAN2

5 GHz(IEEE 802.11)

HyperLANHyperLAN2

2.4–2.4835 GHz83.5 MHz

(IEEE 802.11)

2.4–2.4835 GHz83.5 MHz

(IEEE 802.11)

What is the Wireless LAN Hardware?

Access Points Client Adapters Bridge Antennas

Devices In a Wireless Network

Access Point: An AP operates within a specific frequency spectrum and uses an 802.11 standard specified modulation technique.

It also informs the wireless clients of its availability and authenticates and associates wireless clients to the wireless network.

An AP also coordinates the wireless clients' use of wired resources.

Wireless Access Points

Serves as a connection point for wireless users to connect to the wired LAN

Contention-based, half-duplex deviceNot necessary in Ad Hoc networksPhysical/Data Link Layer deviceHas Layer-2 filtering capabilities1, 2, 5.5, or 11 Mbps connectivity depending on

standard implemented

Think of this device as a 10BaseT hub

Access Point Example

Servers

Wireless Components

Network interface card (NIC)/client adapter: A PC or workstation uses a wireless NIC to connect to the wireless network.

The NIC scans the available frequency spectrum for connectivity and associates it to an access point or another wireless client.

The NIC is coupled to the PC/workstation operating system using a software driver.

Wireless Components

Bridge: Wireless bridges are used to connect multiple LANs (both wired and wireless) at the Media Access Control (MAC) layer level.

Used in building-to-building wireless connections, wireless bridges can cover longer distances than AP’s (IEEE 802.11 standard specifies 1 mile as the maximum coverage range for an AP).

Wireless Bridged Network

Wireless Workgroup Bridge

Users are connected via wired Ethernet to the bridge, which is then connected via wireless Ethernet to the Access Point, which then connects to the wired backbone

Used to connect a small group of users (8 or less) to the wireless network

Users are a "collective client" on the wireless network

Wireless Components

Antenna: An antenna radiates the modulated signal through the air so that wireless clients can receive it.

Characteristics of an antenna are defined by propagation pattern (directional versus omnidirectional), gain, transmit power, and so on.

Antennas are needed on both the AP/bridge and the clients.

Campus Antenna Example

IEEE 802.11 WLAN

Physical

MAC layerIEEE 802.11

LLC layer IEEE 802.2 SNAP

InfraredLight

Direct Sequence

Spread Spectrum

Frequency Hopping Spread

Spectrum

Packet Layer Convergence Protocol (PLCP)

802.11g2.4 GHz – OFDM*

>20Mbps

Proprietary IEEE 802.11a/b Ratified

802.11a Standard5 GHz – OFDM* 54 Mbps

802.11b Standard2.4 GHz – DSSS

11Mbps

1999 2000 2001 2002

NetworkRadioSpeed

2003

*

WLAN Road Map

*Orthogonal Frequency DivisionMultiplexing (OFDM)

802.11b uses complementary Code Keying (CCK) as its modulation scheme

Quadrature Phase Shift Keying

IEEE 802.11 who?

Original recipe 802.11: Ratified June, 1997, 1 or 2Mbps at 2.4Ghz.

The big event- 802.11b (Wi-Fi): 1, 2, 5.5 and 11Mbps, 2.4 GHz, ratified in 1999. Didn’t take off until late 2000. Backward compatible to 802.11

First in line, last to produce products- 802.11a: Up to 54Mbps, 5 GHz, ratified in 1999. Not compatible with 802.11 and 802.11b

802.11a is 5Ghz

Range of 5Ghz is about 30% less then 2.4Ghz Overall investment of infrastructure is much

higher with 5Ghz (for now) Typical 2.4 Ghz range is 150 feet Typical 5Ghz range is 50 feet Not compatible with 802.11a and 802.11b The data rates specified by IEEE 802.11a are

6, 9, 12, 18, 24, 36, 48, and 54 Mbps, with support for 6, 12, and 24 Mbps

IEEE 802.11-tag-along’s

802.11c: Management Group802.11d: Committee trying to add 802.11 into other

countries that can’t use 2.4Ghz. Only Spain now…802.11e: Quality of Service (QoS), multimedia and security

as well as error correction. Uses TDMA like Cisco’s up and coming 802.11a products.

802.11f: Inter-Access Point Protocol (IAPP), Mobile IP802.11g: 54Mbps in 2.4Ghz range802.11h: Group trying to take 802.11a into Europe with

802.11e specs.802.11i: Wireless Authentication and Security802.11j: So new, there is still no members! Group will focus

on 802.11a and HiperLAN2 coexistence

11 and 54Mbs WLAN’s 802.11g

Provides higher date rates at 2.4 Ghz Similar to 802.11b Backward compatible to

– 80211– 802.11b

Other Committees

Wireless Ethernet Compatibility Alliance (WECA): Drafted the Wi-Fi System Interoperability testing document

Wireless Fidelity (Wi-Fi): Agilent Technologies in San Jose performs the independent WLAN products testing. After testing, the WECA board awards the Wi-Fi seal

Wireless Ethernet Compatibility Alliance (WECA)

Mission statement—WECA’s mission is to certify interoperability of Wi-Fi™ (IEEE 802.11b) products and to promote Wi-Fi as the global wireless LAN standard across all market segments

Goal—Provide users with a comfort level for interoperability

Presently over 100 different product certified and growing

• Supports ONLY 802.11b 11MB DS products• Supports ONLY 802.11b 11MB DS products

Other Wireless Technologies

BlueTooth HomeRF ZigBee HiperLAN Homeplug

BlueTooth

Bluetooth is a personal-area network (PAN) specified by the Bluetooth Special Interest Group for providing low-power and short-range wireless connectivity using frequency-hopping spread spectrum in the 2.4-GHz frequency environment.

HomeRF

In 1988, The HomeRF SWAP Group published the Shared Wireless Access Protocol (SWAP) standard for wireless digital communication between PCs and consumer electronic devices within the home.

SWAP supports voice and data over a common wireless interface at 1 and 2-Mbps data rates using frequency-hopping and spread-spectrum techniques in the 2.4-GHz band.

SigBee

Was known as “HomeRF Light” Less then $2 per module for manufacturer Runs off of cheap AA batteries Up to 115kbps From 10 meters to 75 meters All-in-one product (power, tx, rx, ant.)

HiperLAN

HiperLAN is a European Telecommunications Standards Institute (ETSI) standard ratified in 1996. HiperLAN/1 standard operates in the 5-GHz radio band up to 24 Mbps.

ETSI has recently approved HiperLAN/2, which operates in the 5-GHz band at up to 54 Mbps using a connection-oriented protocol for sharing access among end-user devices.

HomePlug Powerline Alliance

• Not-for-profit corporation formed to provide a forum for the creation of open specifications for high speed home powerline networking products and services.

Supposedly works at 14Mbps Don’t turn on a blow dryer… Newly released spec’s fix power spikes

WLAN is not all you need to know…

Third Generation Cell service will provide…..???

Reality: WLAN will deliver mobile high-speed ahead of 3G

802.11b/WiFi

50

500

1 000

10 000

50 000

100 000

Tra

nsm

issi

on r

ate

(kb

it/s)

Terminal device location

HomeRFBluetooth

Fixed LAN

Blackberry (US)

HomeRFBluetooth

802.11a and HiperLAN2

UMTSGPRS

GSM

Wireless Security Methods

Default Settings

Unique SSIDwith Broadcast

SSIDDisabled

Shared KeyAuthentication

with WEP

OpenAuthentication

with WEP

MAC BasedAuthentication

with WEP

EAPAuthentication

with WEP

EAPAuthentication

with MIC,broadcast Keyrotation, and

WEP

Less Secure More Secure

No Security by default….

Internet

Radius Authentication

WLAN Security

Internet

BlueSocket

SummaryThis cable

has GOT

to go! Don’t Delay-

Get “UN”-Hookedwith Wireless…

Hands-on Demonstrations Give Away Time!