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					 Wireless Sensor Systems:
Security Implications for the
  Industrial Environment
          Dr. Peter L. Fuhr
            Chief Scientist
      RAE Systems, Sunnyvale, CA

        pfuhr@raesystems.com
 Dr. Peter Fuhr, Presenter: 480+ publications&presentations in wireless sensor
 networking arena. Old-timer in this area…etc etc.




         RAE Systems Inc.
         • Pervasive Sensing Company
           based in Silicon Valley founded
           in 1991

         Capabilities
                 – Radiation detection
                         • Gamma and neutron
                 – Chemical/vapor detection
                         • Toxic gas, VOC, combustible
                           gas, oxygen, CWA,
                           temperature, humidity, C02
                 – Redeployable sensor networks
                 – Mobile and fixed wireless
                   monitors
                 – Cargo Container Sensor
                   Systems
ISA Wireless Security, P. Fuhr                                               2
                                 Contributors
    A number of individuals have provided “content” for these slides. They
    include:
             Wayne Manges, Oak Ridge National Laboratory
             Robert Poor, Ember
             Pat Gonia, Honeywell
             Hesh Kagan, Foxboro/Invensys
             Kang Lee, NIST
             Tom Kevan, Advanstar
             Ramesh Shankar, Electric Power Research Institute
             Larry Hill, Larry Hill Consulting
             Rob Conant, Dust
             Rick Kriss, Xsilogy
             Gideon Varga, Dept of Energy
             Jack Eisenhauser, Energetics
             Michael Brambley, Pacific Northwest National Labs
             David Wagner, UC-Berkeley

           Undoubtedly, there are other contributors too (apologies if
    your name is not listed).
ISA Wireless Security, P. Fuhr                                               3
              Wireless Sensor Networking
 …it’s not cellular telephony
                    …it’s not just WiFi...(and it just may be the next big thing)




                                              Each dot represents one cell phone tower.

Wireless devices circa 1930
ISA Wireless Security, P. Fuhr                                                            4
                Sensor Market: $11B in 2001
             Installation (wiring) costs: >$100B
                                                             • Fragmented market
                                                                  platform
                                                                 opportunity

                                                             • Installation cost limits
                                                             penetration
                                                                  reducing
                                                                 installation cost
                                                                 increases market size

                                                                 Highly Fragmented
                                                                 Sensor Market
             Freedonia Group report on Sensors, April 2002



ISA Wireless Security, P. Fuhr                                   Slide courtesy of Rob Conant, Dust 5
                   Industrial Market Sizing
                      Sensor Networking Products
•   North American Market for Wireless products used in
    Applications where transmission distances are 1 mile or
    less:
       –    2002 Total: $107 million
       –    2006 Forecast: $713 million
       –    2010 Estimates: $ 2.1 billion


•   Largest Application areas:
       –    2002: Tank Level Monitoring, Asset Tracking, Preventative
            Maintenance
       –    2006: Tank Level Monitoring, Preventative Maintenance,
            Environmental Monitoring


•   Conclusions:
       –    Rapid Growth in Industrial markets
       –    Tank Level Monitoring will remain a significant opportunity
       –    Key ‗ User‘ Needs:
               •   Lower Costs over Wired (or Manual) Solutions
               •   Education of Potential Customers on the Technology
               •   Demonstration of Operational Reliability & Application ‗ Domain‘
                   Knowledge




ISA Wireless Security, P. Fuhr                                                        Slide courtesy of Rick Kriss, Xsilogy   6
             The True cost per monitored node – to the
             End User
              Higher                                                                                       Higher
                                          DENSE                              SPARSE
                                         Bluetooth,                          1xRTT, FLEX
                                      802.15.4, WiFi etc                       SAT, etc




            3-Yr                                                                                      Installation
          TOC $$$                                                                                        Costs
                                                           Design For Here




              Lower                                                                                        Lower


                                 Meters                Radio RF Range (dB)                  Miles
                                   $                                                       $$$$$



                                                                              Slide courtesy of Rick Kriss, Xsilogy
ISA Wireless Security, P. Fuhr                                                                                        7
                                 What to do with the data?
          Parameter
          of Interest                                Output Signal
    Chemical               Measurement System                Chemical
    Electrical                                               Electrical
    Mechanical                                   Output      Mechanical
    Thermal      Sensor          Modifier                    Thermal
    Radiation                                   Transducer   Radiation
    Optical                                                  Optical
    Magnetic                                                 Magnetic
                                 Power
                                 Supply



         Great! But how do you get the output signal from the sensor to the location
            where the information will be interpreted (used)?


 Traditionally the output of the sensor was hardwired to some form of
   interpretive device (e.g., PLC) perhaps relying on a 4-20mA signal…




ISA Wireless Security, P. Fuhr                                                         8
                                 Outline:

 1. Security? Who needs it?
 2. How is security achieved in a wired channel?
 3. The Situation for Wireless (its RF in an industrial setting.
 Spectrum, modulation, encryption, spatial…)
 4. Security within various Wireless Delivery Schemes
 (cellular, WiFi, 802.15.4, Bluetooth, others…)
 5. An Integrated Solution
 6. The Big Review




ISA Wireless Security, P. Fuhr                                     9
            Oh, who needs security in a
             wireless channel anyway!




                                 (pretty ridiculous statement isn‟t it!

ISA Wireless Security, P. Fuhr                                            10
 Let’s ask some experts:
                        WINA meeting, Coral Gables, Sept. 2003




                                 www.wireless4industrial.org

ISA Wireless Security, P. Fuhr                                 11
 What‘s a WINA?




       In the spring of 2003, the Wireless Industrial Networking
       Alliance (WINA) was formed to promote the adoption of
       wireless networking technologies and practices that will help
       increase industrial productivity and efficiency.

       WINA will be holding a 1.5 day meeting at ISA-HQ in RTP, NC on Feb 11/12 –
       right after the ISA Wireless Security Expo and conference. Check out
       www.wireless4industrial.org for WINA meeting details AND
       www.isa.org/wireless for the ISA Wireless Security conf details!
ISA Wireless Security, P. Fuhr                                                  12
 Back to the Question:

 Who needs security in a wireless
 channel anyway!




ISA Wireless Security, P. Fuhr      13
             Strategy Workshop Participants
                        •        Suppliers (13)
                        •        System integrators (6)
                        •        Industrial end users (10)
                                                  – Energy/Utilities
                                  – Chemicals
                                                  – Forest Products
                                  – Petroleum
                                                  – Electronics
                                  – Automotive
                        •        Industry analysts/venture capitalists (3)
                        •        Others (associations, government, media,
                                 researchers)

ISA Wireless Security, P. Fuhr                                               14
                  End-User View of Industrial Wireless
           Likes                      Dislikes
           • Mobility                 • Change to status quo
           • Compactness              • Complexity
           • Flexibility              • High cost for coverage in large
                                        plants
           • Low cost
                                      • Security issues
           • Capability to monitor
                                      • Portability issues (power)
             rotating equipment
                                      • Unproven reliability
           • Short range (security)
                                      • Too risky for process control
           • Ease of installation
                                      • Lack of experience in
           • High reliability           troubleshooting (staff)
           • Impetus to enhance       • Restricted infrastructure
             electronics support        flexibility once implemented
                                      • Lack of analysis tools


ISA Wireless Security, P. Fuhr                                            15
                     Technology Group: Key Issues
        • Security
           – Jamming, hacking, and eavesdropping
        • Power
        • Value (clear to customer)
        • Interoperability
           – Co-existence with other facility networks, sensors,
             collectors, technology
        • True engineered solution (sensors, collectors, etc.)
        • Assured performance & reliability/MTBA*
        • Software infrastructure, data, & systems management
        • Robustness (at least as good as wired)
        • RF characterization (radios, receivers, environments)

ISA Wireless Security, P. Fuhr                                     16
                      *mean time between attention
              Technology Group: Criticality Varies
                by Application (5 = most critical)
                                                      Applications            Biz
       Attributes                Monitor   Control        Alarm   Shutdown   WLAN

       Latency                     2-3       3-5           5          5       1

       Device Reliability          2-3       3-5           5          5       1

       Raw Thru-put               2/5      2.5 /2.5       1/4        1/1      1/5
       (node / aggr.)

       Scalability                 5          4            4          1       2-3
       (Max.# nodes)

       Data Reliability            1          5            5          5       2

       Security                   1-5         5            5         5        5
       Low Cost                    5          2            1-3        1       2-3

       Gateway Technology          5          1            3-4        1       1


       Engineered Solution         1          5            4          5       3




ISA Wireless Security, P. Fuhr                                                      17
                                 Industrial CyberSecurity



                                 • The Case of Vitek Boden




ISA Wireless Security, P. Fuhr                               18
       • On October 31, 2001 Vitek Boden was convicted of:
          – 26 counts of willfully using a restricted computer to
            cause damage
          – 1 count of causing serious environment harm
       • The facts of the case:
          – Vitek worked for the contractor involved in the
            installation of Maroochy Shire sewage treatment
            plant.
          – Vitek left the contractor in December 1999 and
            approached the shire for employment. He was
            refused.
          – Between Jan 2000 and Apr 2000 the sewage
            system experienced 47 unexplainable faults,
            causing millions of liters of sewage to be spilled.

ISA Wireless Security, P. Fuhr                                      19
                                 How did he do it?

         • On April 23, 2000 Vitek was arrested with
           stolen radio equipment, controller
           programming software on a laptop and a fully
           operational controller.
         • Vitek is now in jail…

        Disgruntled
         Contractor



                                    Rogue Radio
                                                       PLC       PLC
                                                  Sewage Plant
ISA Wireless Security, P. Fuhr                                         20
                   A Favorite 2.4 GHz Antenna




ISA Wireless Security, P. Fuhr                  21
              WarDriving – 802.11 HotSpots in
                       Silicon Valley




ISA Wireless Security, P. Fuhr                  22
                 WarDriving – 802.11 HotSpots in
                         San Francisco




ISA Wireless Security, P. Fuhr                     23
 The Question:
 Who needs security in a wireless channel
 anyway!


     The Answer:

     We do. So…How do you provide the
     appropriate level of security within the
     acceptable price and “inconvenience” margin
     -> Risk Management!

ISA Wireless Security, P. Fuhr                     24
                                                Inside vs. Outside?
         • Where do attacks come from?
                                     90

                                     80
                  % of Respondents




                                     70

                                     60

                                     50                                                                2002
                                                                                                       2001
                                     40                                                                2000
                                     30                                                                1999
                                                                                                       1998
                                     20

                                     10

                                     0
                                          Foreign Gov.   Foreign   Hackers      U.S.     Disgruntled
                                                          Corp.              Competitors Employees




        *Source: “2002 CSI/FBI Computer Crime and Security Survey” Computer Security
        Institute - www.gocsi.com/losses.
ISA Wireless Security, P. Fuhr                                                                                25
          An “Outside” Example.
                      When? April 2001




ISA Wireless Security, P. Fuhr           26
                                 “Hacker War I”



               •In the Spring of 2001, the US got it’s first a
               taste of a new form of warfare.
               •Launched from overseas and targeted at
               US critical infrastructure.




ISA Wireless Security, P. Fuhr                                   27
                                  Honker Union
          •Chinese Hacker Group working to advance
          and in some cases impose it’s political agenda
          •During the spring of 2001, Honker Union
          worked with other groups such as the Chinese
          Red Guest Network Security Technology
          Alliance
               •Hackers were encouraged to "...make use of
               their skills for China..." Wired.com

               Attack Methods:
                                  Denial of Service Attacks
                                 •Website Defacement
                                 •E-mailing viruses to US Government Employees
ISA Wireless Security, P. Fuhr
                                 •“KillUSA” package                              28
                                 Cyberwar
          • Cyber attacks and web defacements
            increased dramatically after the start of the
            war against Iraq.
          • More than 1,000 sites were hacked in the
            first 48 hours of the conflict, with many of
            the attacks containing anti-war slogans.
          • Security consultants state that the war
            against Iraq made March the worst month
            for digital attacks since records began in
            1995.


ISA Wireless Security, P. Fuhr                              29
                                 Hacker School
          • North Korea's Mirim College, is a
            military academy specializing in
            electronic warfare
          • 100 potential cybersoldiers graduate
            every year




ISA Wireless Security, P. Fuhr                     30
 The Question:
 Who needs security in a wireless channel
 anyway?




     The Answer:

     Everyone.



ISA Wireless Security, P. Fuhr              31
                                 Outline:

 1. Security? Who needs it?
 2. How is security achieved in a wired channel?
 3. The Situation for Wireless (its RF in an industrial setting.
 Spectrum, modulation, encryption, spatial…)
 4. Security within various Wireless Delivery Schemes
 (cellular, WiFi, 802.15.4, Bluetooth, others…)
 5. An Integrated Solution
 6. The Big Review




ISA Wireless Security, P. Fuhr                                     32
     A few details…

                                 Layered Communications




ISA Wireless Security, P. Fuhr                            33
                            Wired Data Security - Encryption




    The “traditional” method involved encrypting the data prior to
    transmission over a potentially insecure channel. The level of
    protection rests on the encryption algorithm. (There are a few
    other factors…such as the physical media.)

                                                  Slide courtesy of Wayne Manges, ORNL
ISA Wireless Security, P. Fuhr                                                      34
                                 Outline:

 1.       Security? Who needs it?
 2.       How is security achieved in a wired channel?
 3.       The Situation for Wireless
 4.       Security within various Wireless Delivery Schemes
 (cellular, WiFi, 802.15.4, Bluetooth, others…)
 5. An Integrated Solution
 6. The Big Review




ISA Wireless Security, P. Fuhr                            35
 From many perspectives, THIS is what a wireless sensor network can provide.
             Wireless Buildings




                                 Key to success: reduced installation costs
ISA Wireless Security, P. Fuhr                         Slide courtesy of Pat Gonia, Honeywell   36
                                        Modulation
                 E(t) = A(t) cos[wt + f(t)]

       Amplitude Modulation (AM)
        info is in A(t)
       Frequency Modulation (FM)
        info is in w
       Phase Modulation (PM)
        info is in f(t)




         Different vendors use
         different schemes - and they
         are not interoperable.

                                              Phase = 0o           Phase = 360o
                                                  Phase = 180o     (or back to 0o)




                                                            Phase = 270o


ISA Wireless Security, P. Fuhr                                                       37
                      The FCC Frequency Assignment




Different vendors may use
different frequencies within
the various ISM bands
(green in the diagram).




                                  The ISM bands most commonly used are at 433, 915 and 2400 MHz.




 ISA Wireless Security, P. Fuhr                                                                    38
           Multiple Sensors Sharing the Medium:
          Multiplexing. FDMA, TDMA and CDMA




ISA Wireless Security, P. Fuhr                    39
                         Binary Signaling Formats
     • Used to Improve Digital
       Signal Reception and
       Decision
     • NRZ: Non-Return to Zero
     • RZ: Return to Zero
     • Unipolar: Only one side
       of 0V
     • Bipolar: Both sides of 0V
     • Manchester: Bi-Phase
       (“0” in left 1/2 time slot,
       “1” in right)


ISA Wireless Security, P. Fuhr                      40
                         Narrowband or Spread Spectrum?
        Narrowband uses a fixed carrier frequency, F0.




                            The receiver then locks onto the carrier frequency, F0.

                         Easy to implement (inexpensive).
                         Prone to jamming or interference (two transmitters at the
                            same carrier frequency, F0.
                         Least secure modulation scheme.


ISA Wireless Security, P. Fuhr                                                        41
            Narrowband or Spread Spectrum (cont.) ?
        Frequency Hopping Spread Spectrum. Uses
           a carrier frequency that varies with time,
           F0(t).




 Invented and patented by actress Heddy
                                          The receiver must track the time-varying carrier
 Lamarr and her pianist George Antheil.
                                            frequency, F0(t).


     Relatively easy to implement (inexpensive).
     Prone to jamming or interference (two transmitters at the same carrier
        frequency, F0) during any single transmit interval. Hopping rates
        may be ~1600 hops/second (ala Bluetooth).
     Very secure modulation scheme (used in military for decades).
ISA Wireless Security, P. Fuhr                                                          42
              Narrowband or Spread Spectrum (cont.) ?
  Direct Sequence Spread Spectrum uses a fixed carrier frequency, F0
     but interleaves the data with a precise mathematical 0/1 data
     sequence. (This increases the length of the transmitted information
     vector making it longer). The information is replicated many times
     throughout the bandwidth, so if one “lobe” of the information is
     jammed, the remainder “gets through”. Highly robust technique.




                          The receiver then locks onto the carrier frequency, F0 receives the
                             signal and then must ―undo‖ the interleaving.
                                 More difficult to implement (more expensive).
                                 Most complicated scheme (of these presented).
                                 Most secure modulation scheme.
ISA Wireless Security, P. Fuhr                                                                  43
DIRECT-SEQUENCE SPREAD-SPECTRUM SIGNALS
                                      PN Clock                                     Local PN Clock
                                                                                                            Local
                              PN Sequence                                   PN Sequence                     Carrier
            Carrier                                                          Generator
                               Generator

                                     ±1                              Wide          ±1      Narrow           Phase      Data
Data                                                                BP Filter              BP Filter        Demod     Data
       ±1                                                                                                             Clock



        Power                                       Power                                 Power
        Spectral                                    Spectral                              Spectral
        Density                                     Density                               Density




                                                                                                               “Spread”
                                                       RFI                                                       RFI


                         fc                                    fc                                      fc
       Frequency                                   Frequency                            Frequency
                                                                                  Original narrowband, high
                                                 Spectrum has wider bandwidth     power density spectrum is
       Narrow spectrum at                                                         restored if local PN sequence is
                                                 and lower power density after
       output of modulator                       spreading with PN sequence       same as and lined up with
       before spreading                          (PN Rate >> Data Rate)           received PN sequence


ISA Wireless Security, P. Fuhr                                                                                         44
                Narrowband or Spread Spectrum (cont.) ?
                                 Which is
                                  best?




              Each has its pluses and minuses…and each scheme has its share of die-
                 hard advocates and/or naysayers!
                                                        Different vendors use these
                                                        (and other) schemes at
                                                        different frequencies within
                                                        the various ISM bands.

ISA Wireless Security, P. Fuhr
                                 From a security standpoint, DSSS is best.             45
                        Reality




                                 DSSS   FHSS




ISA Wireless Security, P. Fuhr                 46
                       No Matter What…Its Just an
                         Electromagnetic Field

       E(t) = A(t) cos[wt + f(t)]
                           A(t): amplitude of the wave
                           w: radian frequency of the wave
                           f(t): phase of the wave

ISA Wireless Security, P. Fuhr                               47
                                 The RF ―Footprint‖
                                   Network “Size”




      Personal Area Network: typical radiated power: 0 dBm, size: 10m
      Local Area Network: typical radiated power: 20 dBm, size: 100m
      Wide Area Network: typical radiated power: >30 dBm, size: >2000m
ISA Wireless Security, P. Fuhr                                           48
        There are SO many technical questions: such as…

                                 Network Topologies?



                                        Bus Network

                                                                  Tree Network



             Ring Network




                                  Star Network        Ad Hoc Network
ISA Wireless Security, P. Fuhr                                                   49
     The Real World Presents the
 Wireless Channel with Multipath and
 Attenuation…and…




ISA Wireless Security, P. Fuhr         50
    Real World:
                                 Multipath


                                             The Effect




                The Cause




ISA Wireless Security, P. Fuhr                            51
    Real World:
         Atmospheric Attenuation at 2.4 GHz




                                 Rayleigh Fading @ 2.4GHz

ISA Wireless Security, P. Fuhr                              52
    Real World:
         Signal Attenuation at 2.4 GHz




ISA Wireless Security, P. Fuhr           53
    Real World:

           And Signal-to-Noise Ratios really do
           matter!



                         Anecdotal Evidence: As Frankfurt has increased the
                         deployment of 2.4 GHz wireless surveillance cameras,
                         the background Noise level has increased by 12 dB.
                         (This plays havoc with the BER or for fixed BER, the
                         overall data rate,)




ISA Wireless Security, P. Fuhr                                                  54
    Real World:                  Which Frequency is Best?




                  ALERT! ALERT!!
                        Notice that the operation at 2.45 GHz is
                        WORSE than at 900MHz (which is worse
                        than 433 MHz).
ISA Wireless Security, P. Fuhr                                     55
                                 Outline:

 1. Security? Who needs it?
 2. How is security achieved in a wired channel?
 3. The Situation for Wireless (its RF in an industrial setting.
 Spectrum, modulation, encryption, spatial…)
 4. Security within various Wireless Delivery
 Schemes
 (cellular, WiFi, 802.15.4, Bluetooth, others…)
 5. An Integrated Solution
 6. The Big Review




ISA Wireless Security, P. Fuhr                                     56
         Wireless Data Security: Encryption, Spreading, Interleaving




   Wireless networks use a variety of techniques to enhance security,
  such as spreading and interleaving. These techniques can make the
  signal virtually undetectable without prior knowledge about the
  network. This can improve the security of the network by orders
  of magnitude.
                                                     Slide courtesy of Wayne Manges, ORNL
ISA Wireless Security, P. Fuhr                                                              57
                                   The Wireless Market

                     TEXT        GRAPHICS INTERNET    HI-FI   STREAMING     DIGITAL   MULTI-CHANNEL
                                                      AUDIO     VIDEO        VIDEO        VIDEO
             LONG




                                                                                                      LAN
             >




                                                                     802.11b
             RANGE




                                                                          802.11a/HL2 & 802.11g


                                                       Bluetooth 2
             <




                            ZigBee                                                                    PAN
             SHORT




                                                 Bluetooth1



                                           LOW    <    DATA RATE      >   HIGH




ISA Wireless Security, P. Fuhr                                                                              58
                     Bluetooth vs. the Rest (cont‘d)
         Parameter     802.11          HomeRF         Bluetooth       ZigBee (proposed)
         Technology    2.4 GHz, DSSS   2.4GHz, FHSS   2.4 GHz, FHSS   2.4 GHz,DSSS
                       11 chips/bit    50 hops/s      1000+hops/s     15 chips/bit
         Data Rate     11Mbps          1 Mbps         1Mbps           40 kbits/s
         Power         +20 dBm         +20 dBm        0, +20dBm       0dBm
         Range         50m             50m            1-10m, 50m      100m
         Topology      128 devices     128 devices    8 devices,      100s devices,
                       CSMA/CA         CSMA/CA        Piconet         CSMA/CA
         Security      Optional WEP    Optional       Encryption      Not yet
         Voice Channel Optional        Optional       Yes             No




                        Bluetooth – aka IEEE 802.15.1
                        ZigBee – aka IEEE 802.15.4
ISA Wireless Security, P. Fuhr                                                            59
                 Side by Side




ISA Wireless Security, P. Fuhr   60
                                 802.11?




ISA Wireless Security, P. Fuhr             61
The Worldwide View of the 802.11 Spectral
                                 Space




ISA Wireless Security, P. Fuhr           62
                   Radiated Field from a single AP
                           (Kansas City)




ISA Wireless Security, P. Fuhr                       63
           20dB Attenuation Profile for Univ of Kansas
              Eng Bldg., Mesh and AP deployments




ISA Wireless Security, P. Fuhr                           64
                                      WEP
                                         (encrypted traffic)




         • The industry‘s solution: WEP               (Wired Equivalent Privacy)
                 – Share a single cryptographic key among all devices
                 – Encrypt all packets sent over the air, using the shared key
                 – Use a checksum to prevent injection of spoofed packets



ISA Wireless Security, P. Fuhr                                                     65
                                   Early History of WEP

      1997                            802.11 WEP standard released




                                   Simon, Aboba, Moore: some weaknesses
 Mar 2000
                                                             Walker: Unsafe at any key size
 Oct 2000
Jan 30, 2001
 Feb 5, 2001                                                         Borisov, Goldberg, Wagner:
                                  NY Times, WSJ break the story
                                                                      7 serious attacks on WEP
 ISA Wireless Security, P. Fuhr                                                                   66
                                     Subsequent Events

 Jan 2001
                                                                       Borisov, Goldberg, Wagner
Mar 2001
                                 Arbaugh: Your 802.11 network
                                        has no clothes
                                                                       Arbaugh: more attacks …
May 2001
Jun 2001
                                 Newsham: dictionary attacks on WEP keys
Aug 2001
                                 Fluhrer, Mantin, Shamir: efficient attack on way WEP uses RC4

                                 Arbaugh, Mishra: still more attacks
Feb 2002

ISA Wireless Security, P. Fuhr                                                                     67
                                 WEP Attack Tools
          • Downloadable procedures from the Internet
            – To crack the Key:
              • AirSnort
                  – http://airsnort.sourceforge.net
              • WEPCrack
                  – http://sourceforge.net/projects/wepcrack/
            – To brute force enter into WLAN,
              • THC-RUT
                  – http://www.thehackerschoice.com/releases.php




ISA Wireless Security, P. Fuhr                                     68
                 Wi-Fi Protected Access (WPA)
          – Flaws in WEP known since January 2001 - flaws include weak
            encryption, (keys no longer than 40 bits), static encryption keys, lack
            of key distribution method.

          – IEEE developing 802.11i standard for enhanced wireless security -
            Addresses weak data encryption and user authentication within
            existing 802.11 standard.

          – 802.11i standard will not be ratified until late 2003, possibly early
            2004 - outstanding issues.

          – WPA standard joint effort between Wi-Fi Alliance and IEEE - WPA a
            subset of IEEE 802.11i standard (Draft 3.0).

       •WPA provides stronger data encryption (weak in WEP) and user
       authentication (largely missing in WEP).

ISA Wireless Security, P. Fuhr                                                        69
                                 WPA – Data Encryption
       – WPA uses Temporal Key Integrity Protocol (TKIP) - stronger
         data encryption, addresses known vulnerabilities in WEP.
    •TKIP chosen as primary encryption cipher suite -
    Easily deployed and supported in legacy 802.11b
    hardware compared to other available cipher suites.
       – TKIP based on RC4 stream cipher algorithm, surrounds WEP
         cipher engine with 4 new algorithms,
                         1. Extended 48-bit Initialization Vector (IV) and IV sequencing rules
                            (compared to the shorter 24-bit WEP RC4 key).
                         2. New per-packet key mixing function.

                         3. Derivation and distribution method - a.k.a. re-keying.

                         4. A message integrity check (MIC) - a.k.a. „Michael‟, ensures messages
                            haven‟t been tampered with during transmission.
ISA Wireless Security, P. Fuhr                                                                     70
                                            WPA – Data Encryption, cont‘d
     • the Temporal Key Integrity Protocol.


                                  Phase 1
        Temporal Key
                                 key mixing
              TA                                                                WEP seed(s)
                                                                              (represented as
                                                                               WEP IV + RC4
                                                                 Phase 2            key)
                                  TTAK Key
                                                                key mixing
                        TSC
                                  MIC Key
                                                                                               WEP
                                                                                            Encapsulation   Ciphertext
                                                    Plaintext                  Plaintext
                                                    MSDU +                                                  MPDU(s)
                                                                               MPDU(s)
                     SA + DA +                MIC     MIC       Fragment(s)
                   Plaintext MSDU
                         Data




     •DA – Destination Address                             TKIP – Temporal Key Integrity Protocol
     •ICV– Integrity Check Value                           TSC – TKIP Sequence Counter
     •MPDU – Message Protocol Data Unit                    TTAK– result of phase 1 key mixing of Temporal Key
     •MSDU – MAC Service Data Unit                                and Transmitter Address
     •RSN – Robust Security Network                        WEP – Wired Equivalent Privacy
     •SA – Source Address                                  WEP IV – Wired Equivalent Privacy Initialization Vector
     •TA – Transmitter Address

ISA Wireless Security, P. Fuhr                                                                                           71
                                 WPA – Data Encryption, cont’d
      – TKIP implements countermeasures - reduces rate which attacker can
        make message forgery attempts down to two packets every 60
        seconds.

      – After 60 second timeout new PMK or Groupwise Key generated,
        depending on which attacked – ensures attacker cannot obtain
        information from attacked key.

      – Countermeasures bound probability of successful forgery and amount
        of information attacker can learn about a key.

      – TKIP is made available as firmware or software upgrade to existing
        legacy hardware.

  •TKIP eliminates having to replace existing hardware or having to
  purchase new hardware.

ISA Wireless Security, P. Fuhr                                               72
                                 Bluetooth?




ISA Wireless Security, P. Fuhr                73
                            BlueTooth- Some Specifications

         • Uses unlicensed 2.402 - 2.480 GHz frequency range
         • Frequency hopping spread spectrum 79 hops
           separated by 1 MHz
         • Maximum frequency hopping rate: 1600 hops/sec
         • Nominal range: 10 cm to 10 meters
         • Nominal antenna power: 0 dBm
         • One complete Bluetooth data packet can be
           transmitted within each 625 msec hop slot.



ISA Wireless Security, P. Fuhr                                 74
                     Potential Bluetooth Markets




ISA Wireless Security, P. Fuhr                     75
                         Bluetooth Market Forecast




                   Nov‘03: 100M Bluetooth compliant devices worldwide
ISA Wireless Security, P. Fuhr                                          76
                     Bluetooth Protocol Stack
        • Adopted Protocols
           – PPP(Point-To-Point Protocol)
           – TCP/UDP/IP
           – OBEX-Session Protocol for IrDA(Infrared Data
             Association)
           – Contents Fromat(e.g. vCard, vCalendar)
           – WAP-Wireless Application Protocol




ISA Wireless Security, P. Fuhr                              77
                                 Bluetooth Security
     • Supports Unidirectional or Mutual Encryption based
       on a Secret Link key Shared Between Two Devices
     • Security Defined In 3 modes:
        – Mode1- No Security
        – Mode 2 - Service Level Security: Not Established
          Before Channel is Established at L2CAP
        – Mode 3 - Link Level Security: Device Initiates
          Security Before LMP Link is Setup
                    • Devices and Services can be Set for Different Levels of Security
                       – Two Trust Levels are Set for Devices
                          • Trusted Device: Fixed Relationship and Unrestricted
                            Access to All Services
                          • Untrusted: No Permanent relationship and Restricted
                            Services
ISA Wireless Security, P. Fuhr                                                      78
                                 Bluetooth Security
         • Devices and Services can be Set for Different Levels
           of Security
            – Two Trust Levels are Set for Devices
               • Trusted Device: Fixed Relationship and
                 Unrestricted Access to All Services
               • Untrusted: No Permanent relationship and
                 Restricted Services




ISA Wireless Security, P. Fuhr                                    79
                                 Bluetooth Security
    • 3 Levels of Service Access
            – Require Authorization and Authenication
            – Require Authentication Only
            – Default Security for Legacy Applications




ISA Wireless Security, P. Fuhr                           80
          But is this Wireless Link Secure?




       Newsflash: Jan 2001: Norwegian “hackers” crack a
       Bluetooth transmission
ISA Wireless Security, P. Fuhr                            81
        Analysis of a BlueTooth Transmission


                                 High overhead?




ISA Wireless Security, P. Fuhr                    82
                                 802.15.4/Zigbee?




ISA Wireless Security, P. Fuhr                      83
                             IEEE 802.15.4 standard
         • Includes layers up to and including Link Layer Control
                 – LLC is standardized in 802.1
         • Supports multiple network topologies including Star, Cluster Tree and
         • Features of the MAC:
           Mesh
           Association/dissociation, ACK,                ZigBee Application Framework
           frame delivery, channel access                Networking App Layer (NWK)
           mechanism, frame validation,
           guaranteed time slot management,               Data Link Controller (DLC)

           beacon management, channel scan IEEE 802.15.4 LLC LLC, Type I        IEEE 802.2


            • Low complexity: 26 primitives                     IEEE 802.15.4 MAC
              versus 131 primitives for                   IEEE 802.15.4     IEEE 802.15.4
              802.15.1 (Bluetooth)                      868/915 MHz PHY    2400 MHz PHY




ISA Wireless Security, P. Fuhr                                                               84
                                      PHY overview
                                 • Speed
                                    – 20, 40 or 250 kbps
                                 • Channels
                                    – 1 channel in the 868MHz band
                                    – 10 channels in the 915MHz band
                                    – 16 channels in the 2.4GHz band
                                 • Modulation
                                    – BPSK (868MHz/20kbs)
                                    – BPSK (915MHz/40kbps)
                                    – O-QPSK (2.4GHz/250kbps)



                                 • Coexistence w/
                                    – 802.11b DSSS
                                    – 802.15.1 FHSS
                                    – 802.15.3 DSSS

ISA Wireless Security, P. Fuhr                                         85
                                   MAC overview
                                 • Security support
                                 • Power consumption
                                   consideration
                                 • Dynamic channel
                                   selection
                                 • Network topology
                                   – Star topology
                                   – p2p topology
                                   – cluster-tree network
                                     topology

ISA Wireless Security, P. Fuhr                              86
                                 Device classification
                                    • Full Function Device (FFD)
                                       – Any topology
                                       – Can talk to RFDs or other FFDs
                                       – Operate in three modes
                                            • PAN coordinator
                                            • Coordinator
                                            • Device.
                                    • Reduced Function Device (RFD)
                                       – Limited to star topology
                                       – Can only talk to an FFD
                                          (coordinator)
                                       – Cannot become a coordinator
                                       – Unnecessary to send large
                                          amounts of data
                                       – Extremely simple
                                       – Can be implemented using
                                          minimal resources and memory
                                          capacity
ISA Wireless Security, P. Fuhr                                            87
                       Transmission management
                                 • Acknowledgement
                                   –No ACK
                                   –ACK
                                   –Retransmission
                                   –Duplicate detection
                                 • Indirect transmission




ISA Wireless Security, P. Fuhr                             88
                                       Security

                                 • Unsecured mode
                                 • ACL mode
                                   – Access control
                                 • Secured mode
                                   – Access control
                                   – Data encryption
                                   – Frame integrity
                                   – Sequential freshness



ISA Wireless Security, P. Fuhr                              89
                                 Scalable Security

         • Assume the attacker can deploy own nodes (can
           create a ―ring‖ at some distance from
           controller)[Wisenet 2003]
         • Enemy nodes ―mimick‖ the mesh nodes; they
           ACK the ―health inquiry‖ as if everything was OK
           – but they do not forward to the rest of the net
         • The rest of the network is virtually cut off from
           inspection by controller
         • Need secure key and a random seed that changes
           at each round


ISA Wireless Security, P. Fuhr                                 90
                                 What About:

 1451.5?
      1xRTT?
          SAT?
                                     CDPD?
                                         Others?

                                               No time this morning!




ISA Wireless Security, P. Fuhr                                         91
                                 Outline:

 1. Security? Who needs it?
 2. How is security achieved in a wired channel?
 3. The Situation for Wireless (its RF in an industrial setting.
 Spectrum, modulation, encryption, spatial…)
 4. Security within various Wireless Delivery Schemes
 (cellular, WiFi, 802.15.4, Bluetooth, others…)
 5. An Integrated Solution
 6. The Big Review




ISA Wireless Security, P. Fuhr                                     92
        There are SO many technical questions: such as…

                          Integrated Industrial Networks?




         If the sensor network is to integrate into an industrial setting, then you
         should be cognizant of the Industrial Networking arena.
ISA Wireless Security, P. Fuhr                                                        93
                       Industrial Device Network Topology




   •     Typically, three layers of networking make up enterprisewide networks. Ethernet
         acts as the company's intranet backbone, and it's linked to controllers or
         industrial PCs, which supply strategic data to the enterprise. An industrial
         network, or fieldbus, links sensors and smart devices. A gateway (not uncommon
         in a large system with lots of devices) links devices that have only RS-232 or RS-
         485 ports to the fieldbus system.

ISA Wireless Security, P. Fuhr                                                          94
                      Industrial Device Networks
          • General characteristics for industrial device
            networks have arisen.




         •      Obviously the complexity of the network increases as the
                functionality is increased.

ISA Wireless Security, P. Fuhr                                             95
                        Classification of Industrial
                                 Networks



     • Three logical groupings of instrumentation
       networks used in an industrial setting.
     • There are over 100 different proprietary
       networks in the field.
ISA Wireless Security, P. Fuhr                         96
                             Inside Security Incident
         • Employee attacks PLC in another plant area
           over PLC highway.
         • Password changed to obscenity, blocking
           legitimate maintenance and forcing process
           shutdown.
                                              Plant Highway
                                                                        Disgruntled
                                                                        Employee

                                 PLC   PLC    PLC     PLC
                        Steam Plant          Paper Plant

          * Source: BCIT Industrial Security Incident Database (ISID)
ISA Wireless Security, P. Fuhr                                                        97
                                       Network Positioning
                           -                               Data                          +
           +




                                                                                             +
                                                                       Ethernet TCP/IP

                                                           ControlNet
           Functionality




                                                      Foundation Fieldbus H2




                                                                                             Complexity
                                               Profibus-DP         Profibus-FMS
                                               Interbus-S          Data Highway+
                                               Remote I/O          Modbus Plus

                                DeviceNet    Fieldbus H1
                                Other CAN    Profibus-PA
                                SDS          Modbus
                                             HART

                                   ASi, Seriplex,
                               Hardwiring, RS485 etc.
           -




                                                                                             -
                           -                               Cost                          +

ISA Wireless Security, P. Fuhr                                                                            98
            Too Focused on Internet Issues?
         • Myth #1: Our SCADA/PLC/DCS is safe if
           we don‘t connect to the Internet.
         • Myth #2: Our Internet firewall will protect
           our control systems.
         • Myth #3: Our IT department understands
           process control issues and security.



ISA Wireless Security, P. Fuhr                           99
           Is Industrial Comm Security Too
              Focused on Internet Issues?                                Enterprise
                                                                     Resource Planning
                                                                  Manufacturing Logistics
                                   Internet
                                                                        Production

              Remote                              Firewall               Planning

              Engineering
                                                   Enterprise Network



                                              Production Networks
                                                             Ethernet                       Process
                                                                                            Historian
                                                    SCAD
           Programming Stations                     A                                                    WarDialing
                                                       Control
                                                       Network                                           Attack
                                   PLC                        PLC
                                                                                        Modem


          Handheld               802.11
          Operator               WLAN                                                              OEM
          Terminal                                      Field Devices

        Source (used by permission): Interface Technologies, Windsor, CT, 2002
ISA Wireless Security, P. Fuhr                                                                                        100
                                 Outline:

 1. Security? Who needs it?
 2. How is security achieved in a wired channel?
 3. The Situation for Wireless (its RF in an industrial setting.
 Spectrum, modulation, encryption, spatial…)
 4. Security within various Wireless Delivery Schemes
 (cellular, WiFi, 802.15.4, Bluetooth, others…)
 5. An Integrated Solution
 6. The Big Review




ISA Wireless Security, P. Fuhr                                     101
                   Bit Rate vs. Quality of Service


         How Many
         Bits are
         Needed?




  The more bits
    you xmit,
    the more
    power you
    consume!
ISA Wireless Security, P. Fuhr                       102
                    Coding vs. Quality of Service


         Is Coding
         Really
         Necessary?




ISA Wireless Security, P. Fuhr                      103
                   Direct Sequence Spread Spectrum




ISA Wireless Security, P. Fuhr                       104
                                 Comparing Wireless


         Tech.                   Range   RF      Battery   Numbers
                                         Power   life      In Area

         DSSS                    Medium Low      longest   High


         FHSS                    Long    High    Short     Medium


         UWB                     Medium Lowest   short     High

ISA Wireless Security, P. Fuhr                                       105
                 Technology Beats Marketing in
                         Performance!
                         Technology versus Attributes
                         Summary Chart

                                            Technology
                      DSSS        CDMA      Low      Mobile                                                          BPSK    900MHz
                      FHSS        TDMA      Power Ad Hoc       Power        Embedded                       Open      QPSK    2.4GHz
   Attribute          UWB         FDMA      Designs Networks   Harvesting   Intelligence Diversity   FEC   Standards M-ary   5.8GHz
   Long Range         NA          NA        NA       yes       NA           NA           yes         yes   NA        NA      900MHz
   Plug-and-Play      DSSS        CDMA      NA       NA        NA           NA           NA          NA    yes       NA      NA
   Long Battery life FHSS         FDMA      yes      NA        yes          yes          yes         yes   NA        M-ary   900MHz
   Low RFI risk       DSSS        NA        yes      yes       NA           yes          yes         NA    NA        NA      5.8GHz
   Self Locating      DSSS        CDMA      NA       NA        NA           yes          yes         NA    NA        NA      5.8GHz
   Secure             UWB         CDMA      yes      NA        NA           yes          yes         NA    NA        NA      5.8GHz
   High throughput    UWB         NA        NA       NA        NA           yes          yes         yes   NA        M-ary   5.8GHz
   non line-of-sight  UWB         NA        NA       yes       NA           NA           yes         NA    NA        NA      900MHz
   robust connections DSSS        CDMA      NA       yes       NA           NA           yes         yes   NA        BPSK    5.8GHz
   low cost           FHSS        FDMA      yes      NA        NA           NA           NA          NA    yes       BPSK    900MHz
   small size         FHSS        TDMA      yes      NA        NA           NA           NA          NA    NA        BPSK    5.8GHz




ISA Wireless Security, P. Fuhr                                                                                                        106
                   Statistics on Types of Attacks
                             Denial of Service

                                  Laptop Theft

                                 Active Wiretap

                                 Telecom Fraud
                                                                                 1997
         Unauthorized Insider Access
                                                                                 1998
                                         Virus                                   1999
                                 Finacial Fraud                                  2000
                                                                                 2001
          Insider Abuse of Net Access                                            2002
                       System Penetration

                   Telecom Evesdropping

                                      Sabotage

                    Theft of Propriety Info

                                                  0   20   40   60   80   100    120
                                                  % of Respondents
        *Source: “2002 CSI/FBI Computer Crime and Security Survey” Computer Security
        Institute - www.gocsi.com/losses.

ISA Wireless Security, P. Fuhr                                                          107
         Optimization of Security vs. Cost
         • Risk reduction is balanced against the cost of
           security counter measures to mitigate the risk.


                                            Optimal Level of Security
                                            at Minimum Cost

                     Cost ($)


                                 Cost of Security                   Cost of Security
                                 Countermeasures                    Breaches



                                               Security Level

ISA Wireless Security, P. Fuhr                                                         108
                          Risk in Safety vs. Risk in Security

         • Safety Definition: “Risk is a measure of
           human injury, environmental damage, or
           economic loss in terms of both the incident
           likelihood and the magnitude of the loss or
           injury.”
         • Security Definition: “Risk is an expression of
           the likelihood that a defined threat will exploit
           a specific vulnerability of a particular
           attractive target or combination of targets to
           cause a given set of consequences.”
        *Source: CSPP Guidelines For Analyzing And Managing The Security
        Vulnerabilities Of Fixed Chemical Sites
ISA Wireless Security, P. Fuhr                                             109
                                       Firewall Architectures

         • The external router blocks attempts to use the
           underlying IP layer to break security (e.g. IP
           spoofing, source routing, packet fragments, etc) and
           forces all traffic to the proxy.
         • The proxy firewall handles potential security holes in
           the higher layer protocols.
         • The internal router blocks all traffic except to the
           proxy server.
                                            External       Internal
                                             Router         Router
                            Internet
                                                      

ISA Wireless Security, P. Fuhr                                        110
                          There‘s lot of ―Wireless‖
         • From cellphones to PDAs to WiFi to
           Satellite-based




ISA Wireless Security, P. Fuhr                        111
                           Wireless LAN Standards




ISA Wireless Security, P. Fuhr                      112
                                  Existing/Developing
                                 IEEE 802.11 Standards
  •      802.11-                  Frequency Hopping/DSSS
  •      802.11a –                54Mbps / HyperLAN
  •      802.11b –                (1999) 11Mbps
  •      802.11e –                Quality of Service
  •      802.11f –                Point 2 Point Roaming
  •      802.11g –                (2003) 54Mbps
  •      802.11h –                European Inspired Changes
  •      802.11i –                (Q2,2004) New Encryption Protocols
  •      802.1x –                 (Q2,2004) Port Based Network Access
  •      802.15 –                 Personal Area Network (WPAN)
  •      802.16 –                 Wireless Metropolitan Area Network (WMAN)

ISA Wireless Security, P. Fuhr                                                113
                 Wireless Backbone for Inflight “Entertainment”

On-Board Network Integration                     PicoCell
                                                   BTS
                                                               PicoCell
                                                                 BTS
                                                                           Noise
                                                                           Floor
                                                                           Lifter




                                                        6 MCU
                                                                          SDU
                                                      GSM SERVER




ISA Wireless Security, P. Fuhr       …and we haven’t even touched on RFID!
                                                                        114
                          There‘s lot of ―Wireless‖
         • And it all needs to feel more Secure!




ISA Wireless Security, P. Fuhr                        115
              For a real review of networking
                          security…
         • Take Eric Byrnes ISA course IC32C…




ISA Wireless Security, P. Fuhr                  116
                                  Will History Repeat?

  Cellular networks                                     wireless security: not just 802.11
1980 analog cellphones: AMPS



           analog cloning, scanners    wireless networks
           fraud pervasive & costly
         digital: TDMA, GSM             1999 802.11, WEP
1990
           TDMA eavesdropping [Bar]     2000                             sensor networks
                                        2001    WEP broken [BGW]                Proprietary systems
           more TDMA flaws [WSK]                WEP badly broken [FMS]
           GSM cloneable [BGW]                   attacks pervasive      2002
           GSM eavesdropping            2002
                                                                                1451, 802.15.4, TinyOS
              [BSW,BGW]
2000                                    2003 WPA                         2003
         Future: 3rd gen.: 3GPP, …             Future: 802.11i                  Future: ???
 ISA Wireless Security, P. Fuhr                                                                  117
                                 PATRIOT Act
          • PATRIOT (Provide Appropriate Tools
            Required to Intercept and Obstruct
            Terrorism)
          • Legally classifies many hacking attacks
            as acts of terrorism




ISA Wireless Security, P. Fuhr                        118
               So… If Nothing else, at least
               PLEASE do this for your WiFi
                        System!

                   WLAN Security Countermeasures
        • Conduct site survey
               • Identify areas of signal strength and weakness
               • Do a “walkaround” with NetStumbler
               • Document and shut down rogue access points
               • Document and shut down unauthorized wireless
                 NICs
               • AND TURN ON SOME LEVEL OF THE
                 PROVIDED PROTECTION!
ISA Wireless Security, P. Fuhr                                    119
                                 Oh…

  And don’t forget that as you layer in all of
 these wacky encryption schemes and
 CDMA and DSSS and…and… that it takes
 some joules to actually implement this. So
 if your wireless network has primepower
 (a.k.a. AC) you’re ok. But if you’re going
 off a battery then it’s a tradeoff of security
 versus Power Consumption  You
 Choose that one!

ISA Wireless Security, P. Fuhr                    120
                                     ...and in the end...




                        BumbleBee with RF xcvr



                                                 ...or...


       HoneyBee with RFID


                                 Two potential forms of wireless sensor networks.
                                             And they should both be secure!
ISA Wireless Security, P. Fuhr                                                      121
                                 Outline:

 1. Security? Who needs it?
 2. How is security achieved in a wired channel?
 3. The Situation for Wireless (its RF in an industrial setting.
 Spectrum, modulation, encryption, spatial…)
 4. Security within various Wireless Delivery Schemes
 (cellular, WiFi, 802.15.4, Bluetooth, others…)
 5. An Integrated Solution
 6. The Big Review
 7. Glossary and References




ISA Wireless Security, P. Fuhr                                     122
                                                           Glossary
10BASE-T: IEEE 802.3 standard for a twisted-pair Ethernet network. 10 Mbps transmission rate over baseband using unshielded, twisted-
pair cable.

802.11: The IEEE 802.11 standard defines both frequency hopping and direct sequence spread spectrum solutions for use in the 2.4-2.5 MHz
ISM (Industrial, Scientific, Medical) band.

802.11a: The Global System for Mobile Communications standard for worldwide wireless communications on wide area networks (WANs).

802.11b: The portion of the 802.11 specification that defines the 11 Mbps data rate.

A

Access Point: Provides a bridge between Ethernet wired LANs and the wireless network. Access points are the connectivity point between
Ethernet wired networks and devices (laptops, hand-held computers, point-of-sale terminals) equipped with a wireless LAN adapter card.

Analog phone: Comes from the word "analogous," which means similar to. In telephone transmission, the signal being transmitted from the
phone—voice, video or image—is analogous to the original signal.

Antenna-Directional: Transmits and receives radio waves off the front of the antenna. The power behind and to the sides of the antenna is
reduced. The coverage area is oval with the antenna at one of the narrow ends. Typical directional antenna beam width angles are from 90°
(somewhat directional) to as little as 20°(very directional). A directional antenna directs power to concentrate the coverage pattern in a
particular direction. The antenna direction is specified by the angle of the coverage pattern called the beam width.

Antenna-Omni-directional: Transmits and receives radio waves in all directions. The coverage area is circular with the antenna at the center.
Omni-directional antennas are also referred to as whip or low-profile antennas.

Association: The process of determining the viability of the wireless connection and establishing a wireless network's root and designated
access points. A mobile unit associates with its wireless network as soon as it is powered on or moves into range.

ATM: Asynchronous Transfer Mode. A type of high-speed wide area network.


ISA Wireless Security, P. Fuhr                                                                                                               123
                                                          Glossary
B

Backbone: A network that interconnects other networks, employing high-speed transmission paths and often spanning a large geographic
area.

Bandwidth: The range of frequencies, expressed in hertz (Hz), that can pass over a given transmission channel. The bandwidth determines
the rate at which information can be transmitted through the circuit.

Bandwidth Management: Functionality that allocates and manages RF traffic by preventing unwanted frames from being processed by the
access point.

BC/MC: Broadcast frames; Multicast frames

Beacon: A uniframe system packet broadcast by the AP to keep the network synchronized. A beacon Includes the Net_ID (ESSID), the AP
address, the Broadcast destination addresses, a time stamp, a DTIM (Delivery Traffic Indicator Maps) and the TIM (Traffic Indicator
Message).

BFA Antenna Connector: Miniature coaxial antenna connector manufactured by MuRata Manufacturing Corporation.

Bluetooth: See Wireless Personal Area Networks.

Bridge: A device that connects two LANs of the same or dissimilar types. It operates at the Data Link Layer, as opposed to routers. The
bridge provides fast connection of two collocated LAN segments that appear as one logical network through the bridge.

Buffer: A segment of computer memory used to hold data while it is being processed.




ISA Wireless Security, P. Fuhr                                                                                                            124
C                                                             Glossary
CAM: Continuously Aware Mode: Mode in which the adapter is instructed to continually check for network activity.

Card and Socket Services: Packages that work with the host computer operating system, enabling the Wireless LAN adapter to interface with
host computer configuration and power management functions.

Cellular Phone: Low-powered, duplex, radio/telephone that operates between 800 and 900 MHz, using multiple transceiver sites linked to a
central computer for coordination. The sites, or "cells," cover a range of one to six or more miles in each direction.

Centrex: Business telephone service offered by a local telephone company from a local telephone company office. Centrex is basically a single
line phone system leased to businesses as a substitute for a business that is buying or leasing its own on-premises phone system or PBX.

CDMA and TDMA: The Code Division Multiple Access and Time Division Multiple Access standard for wireless communications on wide
area networks (WANs) in North America.

Circuit switching: The process of setting up and keeping a circuit open between two or more users so that users have exclusive and full use of
the circuit until the connection is released.

Client: A computer that accesses the resources of a server.

Client/Server: A network system design in which a processor or computer designated as a server (such as a file server or database server)
provides services to other client processors or computers.

CODEC: Coder-Decoder. Audio compression/decompression algorithm that is designed to offer excellent audio performance. Converts voice
signals from their analog form to digital signals acceptable to modern digital PBXs and digital transmission systems. It then converts those
digital signals back to analog so that you may hear and understand what the other person is saying.

Computer Telephony Integration: Technology that integrates computer intelligence with making, receiving, and managing telephone calls.
Computer telephony integrates messaging, real-time connectivity, and transaction processing and information access.




ISA Wireless Security, P. Fuhr                                                                                                              125
                                                           Glossary
D

Data Terminal: Computer transmit and receive equipment, including a wide variety of dumb terminals or terminals without embedded
intelligence in the form of programmed logic. Most data terminals provide a user interface to a more capable host computer, such as a
mainframe or midrange computer.

Decryption: Decryption is the decoding and unscrambling of received encrypted data. The same device, host computer or front-end
processor, usually performs both encryption and decryption.

Desktop Conferencing: A telecommunications facility or service on a PC that permits callers from several diverse locations to be connected
together for a conference call.

Digital Phone System: Proprietary phone system provided by a vendor, such as AT&T, Mitel, Northern Telecom, and so on. The signal being
transmitted in a digital phone system is the same as the signal being transmitted in an analog phone system. The system can consist of a
proprietary PBX system that converts voice signals from their analog form to digital signals, and then converts those digital signals back to
analog. Alternatively, the conversion from analog-to-digital can occur in a digital phone.

Direct Inward Dialing: DID. The ability for a caller outside a company to call an internal extension without having to pass through an
operator or attendant. In large PBX systems, the dialed digits are passed from the PSTN to the PBX, which then completes the call.

Direct-Sequence (DS) Spread Spectrum: Direct sequence transmits data by generating a redundant bit pattern for each bit of information
sent. Commonly referred to as a "chip" or "chipping code," this bit pattern numbers 10 chips to one per bit of information. Compared with
frequency hopping, direct sequence has higher throughput, wider range and is upgradable in the 2.4GHz band.

Diversity Reception: The use of two antennas attached to a single access point to improve radio reception. The second antenna is used only
for receiving radio signals, while the primary is used for both transmitting and receiving.

Driver: A program routine that links a peripheral device, such as a mobile unit's radio card, to the computer system.




ISA Wireless Security, P. Fuhr                                                                                                            126
                                                                           Glossary
Element-level Management: Level of technologies aimed at small or medium-sized businesses.

Encryption: Entails scrambling and coding information, typically with mathematical formulas called algorithms, before the information is transmitted over a network.

Ethernet: A local area network used for connecting computers, printers, workstations, terminals, servers, and so on, within the same building or campus. Ethernet
operates over twisted wire and over coaxial cable at speeds up to 100 Mbps, with 1 Gbps speeds coming soon.

Filtering: Prevents user-defined frames from being processed by the access point.

Fragmentation Threshold: The maximum size for directed data packets transmitted over the radio. Larger frames fragment into several packets this size or smaller before
transmission over the radio. The receiving station reassembles the transmitted fragments.

Frame Mode: A communications protocol supported by the OEM Modules. The frame protocol implements asynchronous serial Point-to-Point (PPP) frames similar to
those used by serial Internet protocols.

Frequency Hopping (FH) Spread Spectrum: Hedy Lamarr, the actress, is credited in name only for inventing frequency hopping during World War II. As its label
suggests, frequency hopping transmits using a narrowband carrier that changes frequency in a given pattern. There are 79 channels in a 2.4GHz ISM band, each channel
occupying 1MHz of bandwidth. A minimum hop rate of 2.5 hops per channel per second is required in the United States. Frequency hopping technology is recognized as
superior to direct sequence in terms of echo resistance, interference immunity, cost and ease-of-installation. To date, there has also been a greater selection of WLAN
products from which to chose.

FTP (File Transfer Protocol): A common Internet protocol used for transferring files from a server to the Internet user. It uses TCP/IP commands.

Gain, dBi: Antenna gain, expressed in decibels referenced to a half wave dipole.

Gain, dBi: Antenna gain, expressed in decibels referenced to a theoretical isotropic radiator.

Gain, dBic: Antenna gain, expressed in decibels referenced to a theoretical isotropic radiator that is circularly polarized.

Gatekeeper: Software that performs two important functions to maintain the robustness of the network: address translation and bandwidth management. Gatekeepers map
LAN aliases to IP addresses and provide address lookups when needed.

Gateway: Optional element in an H.323 conference. Gateways bridge H.323 conferences to other networks, communications protocols, and multimedia formats.
Gateways are not required if connections to other networks or non-H.323 compliant terminals are not needed.

GHz: International unit for measuring frequency is Hertz (Hz), which is equivalent to the older unit of cycles per second. One Gigahertz (GHz) is one billion Hertz.
Microwave ovens typically operate at 2.45 GHz.

GSM: The Global System for Mobile Communications standard for worldwide wireless communications on wide area networks (WANs).

ISA Wireless Security, P. Fuhr                                                                                                                                         127
                                                                        Glossary
H.323: An umbrella standard from the International Telecommunications Union (ITU) that addresses call control, multimedia management, and bandwidth management
for point-to-point and multi-point conferences, as well as interfaces between LANs and other networks. The most popular standard currently in use.

Handheld PC (HPC): The term adopted by Microsoft and its supporters to describe handheld computers employing Microsoft's Windows CE operating system.

Interactive Voice Response: System used to access a database access application using a telephone. The voice processing acts as a front-end to appropriate databases that
reside on general purpose computers. For instance, DTMF (touch tone) input of a Personal Identification Number can be required for access or more unusual and
expensive techniques such as voice recognition and voice print matching.

Internet: World's largest network, often referred to as the Information Superhighway. The Internet is a virtual network based on packet switching technology. The
participants on the Internet and its topology change on a daily basis.

Internet Commerce: Electronic business transactions that occur over the Internet. Samples of Internet commerce applications include electronic banking, airline
reservation systems, and Internet malls.

Internet Phone: Device used to transmit voice over the Internet, bypassing the traditional PSTN and saving money in the process. An Internet phone can be a small phone
(such as the NetVision Phone) or a multimedia PC with a microphone, speaker, and modem.

Interoperability: The ability of equipment or software to operate properly in a mixed environment of hardware and software, from different vendors. Enabled by the
IEEE 802.11 open standard.

IP (Internet Protocol): The Internet standard protocol that defines the Internet datagram as the unit of information passed across the Internet. Provides the basis of the
Internet connection-less- best-effort packet delivery service. The Internet protocol suite is often referred to as TCP/IP because IP is one of the two fundamental protocols.

International Roaming: Ability to use one adapter worldwide.

Intranet: A private network that uses Internet software and Internet standards. In essence, an intranet is a private Internet reserved for use by people who have been given
the authority and passwords necessary to use that network.

ISDN: Integrated Services Digital Network. Emerging network technology offered by local phone companies that is designed for digital communications, computer
telephony, and voice processing systems.

ISM Band: ISM bands--instrumental (902-928MHz), science (2.4-2.4835GHz), and medical (5.725-5.850GHz)--are the radio frequency bands allocated by the FCC for
unlicensed continuous operations for up to 1W. The most recent band approved by the FCC for WLANs was the medical band in January 1997.

ITU: International Telecommunications Union. Standards body that defined H.323 and other international standards.

Jitter: Noise on a communications line which is based on phase hits, causing potential phase distortions and bit errors..
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                                                                        Glossary
Kerberos: A widely deployed security protocol that was developed at the Massachusetts Institute of Technology (MIT) to authenticate users and clients in a wired
network environment and to securely distribute encryption keys.

Key Telephone System: A system in which the telephone has multiple buttons permitting the user to directly select central office phone lines and intercom lines. Key
phone systems are most often found in relatively small business environments, typically around 50 telephones.

Layer: A protocol that interacts with other protocols as part of an overall transmission system.

LPD (Line Printer Daemon): A TCP-based protocol typically used between a Unix server and a printer driver. Data is received from the network connection and sent out
over the serial port.

MAC (Media Access Control): Part of the Data Link Layer, as defined by the IEEE, this sublayer contains protocols for gaining orderly access to cable or wireless
media.

MD5 Encryption: An authentication methodology when MU is in foreign subnet.

MIB (Management Information Base): An SNMP structure that describes the specific device being monitored by the remote-monitoring program.

Microcell: A bounded physical space in which a number of wireless devices can communicate. Because it is possible to have overlapping cells as well as isolated cells,
the boundaries of the cell are established by some rule or convention.

Modem: Equipment that converts digital signals to analog signals and vice versa. Modems are used to send digital data signals over the analog PSTN.

MMCX Antenna Connector: Miniature coaxial antenna connector in use by several major wireless vendors.

Mobile IP: The ability of the mobile unit to communicate with the other host using only its home IP address, after changing its point of attachment to the Internet and
intranet.

Mobile Unit (MU): May be a Symbol Spectrum24 terminal, PC Card and PCI adapter, bar-code scanner, third-party device, and other

Mobile Unit Mode: In this mode, the WLAN adapter connects to an access point (AP) or another WLAN installed system, allowing the device to roam freely between
AP cells in the network. Mobile units appear as network nodes to other devices.

Modulation: Any of several techniques for combining user information with a transmitter's carrier signal.

Multipath: The signal variation caused when radio signals take multiple paths from transmitter to receiver.

Multipath Fading: A type of fading caused by signals taking different paths from the transmitter to the receiver and, consequently, interfering with each other.
ISA Wireless Security, P. Fuhr                                                                                                                                            129
Node: A network junction such as a switch or a routing center.         Glossary
Packet Switching: Refers to sending data in packets through a network to some remote location. In a packet switched network, no circuit is left open on a dedicated basis.
Packet switching is a data switching technique only.

PBX Phone System: Private Branch eXchange. Small version of the phone company's larger central switching office. An alternative to a PBX is to subscribe to a local
telephone company's Centrex service.

PCMCIA (Personal Computer Memory Card International Association) PC Card: A credit card-size device used in laptop computers and available as removable network
adapters.

PCS (Personal Communications Service): A new, lower powered, higher-frequency competitive technology to cellular. Whereas cellular typically operates in the 800-
900 MHz range, PCS operates in the 1.5 to 1.8 GHz range. The idea with PCS is that the phone are cheaper, have less range, and are digital. The cells are smaller and
closer together, and airtime is cheaper.

Peer-to-peer Network: A network design in which each computer shares and uses devices on an equal basis.

Ping: A troubleshooting TCP/IP application that sends out a test message to a network device to measure the response time.

PLD (Data Link Protocol): A raw packet protocol based on the Ethernet frame format. All frames are sent to the wireless network verbatim--should be used with care as
improperly formatted data can go through with undesirable consequences.

Plug and Play: A feature that allows a computer to recognize the PCI adapter and configure the hardware interrupt, memory, and device recognition addresses; requires
less user interaction and minimizes hardware conflicts.

Pocket PC: The term adopted by Microsoft and its supporters to describe handheld computers employing Microsoft's Pocket PC operating system.

Point-of-Sale Device: A special type of equipment that is used to collect and store retail sales data. This device may be connected to a bar code reader and it may query a
central computer for the current price of that item.

POTS (Plain Old Telephone Service): The basic service supplying standard single line telephones, telephone lines, and access to the public switched telephone network.

Power Management: Algorithms that allow the adapter to sleep between checking for network activity, thus conserving power.

PSP (Power Save Polling): stations power off their radios for long periods. When a mobile unit in PSP mode associates with an access point, it notifies the AP of its
activity status. The AP responds by buffering packets received for the MU.

PSTN (Public Switched Telephone Network): Refers to the worldwide voice telephone network accessible to all those with telephones and access privileges. In the U.S.,
the PSTN is provided by AT&T.

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                                                                         Glossary
QoS (Quality of Service): Measure of the telephone service quality provided to a subscriber. QoS refers to things like: Is the call easy to hear? Is it clear? Is it loud
enough?


RBOC (Regional Bell Operating Company): One of the seven Bell operating companies set up after the divestiture of AT&T, each of which own two or more Bell
Operating Companies (BOCs).

Roaming: Movement of a wireless node between two microcells. Roaming usually occurs in infrastructure networks built around multiple access points.

Repeater: A device used to extend cabling distances by regenerating signals.

Router: The main device in any modern network that routes data blocks from source to destination using routing tables and determining the best path dynamically. It
functions as an addressable entity on the LAN and is the basic building block of the Internet.


SNMP (Simple Network Management Protocol): The network management protocol of choice for TCP/IP based intranets. Defines the method for obtaining information
about network operating characteristics, change parameters for routers and gateways.

Scanning: A periodic process where the mobile unit sends out probe messages on all frequencies defined by the country code. The statistics enable a mobile unit to re-
associate by synchronizing its frequency to the AP. The MU continues communicating with that access point until it needs to switch cells or roam.

Site Survey: Physical environment survey to determine the placement of access points and antennas, as well as the number of devices necessary to provide optimal
coverage, in a new or expanding installation.

Spread Spectrum: A transmission technique developed by the U.S. military in World War II to provide secure voice communications, spread spectrum is the most
commonly used WLAN technology today. It provides security by "spreading" the signal over a range of frequencies. The signal is manipulated in the transmitter so that
the bandwidth becomes wider than the actual information bandwidth. De-spreading the signal is impossible for those not aware of the spreading parameters; to them, the
signal sounds like background noise. Interference from narrowband signals is also minimized to background noise when it is de-spread by the receiver. Two types of
spread spectrum exist: direct sequence and frequency hopping.

Stream Mode: A communications protocol supported only by the Telnet and TCP protocols. Stream mode transfers serial characters as they are received by encapsulating
them in a packet and sending them to the host.




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                                                                     Glossary
  T1: A type of dedicated digital leased-line available from a public telephone provider with a capacity of 1.544 Mbps. A T1 line can normally handle 24 voice
  conversations, each one digitized at 64 Kbps. With more advanced digital voice encoding techniques, it can handle more voice channels. T1 is the standard for digital
  transmission in the U.S. Canada, Hong Kong, and Japan.

  TCP/IP: Networking protocol that provides communication across interconnected networks, between computers with diverse hardware architectures, and various
  operating systems. TCP/IP is used in the industry to refer to the family of common Internet protocols.

  TCP (Transport Communication Protocol): Controls the transfer of data from one client to one host, providing the mechanism for connection maintenance, flow control,
  retries, and time-outs.

  Telnet (Terminal Emulation Protocol): A protocol that uses the TCP/IP networking protocol as a reliable transport mechanism. Considered extremely stable.

  Terminal: An endpoint, which provides for real-time, two-way communications with another terminal, gateway, or mobile unit.

  Token Ring: A ring type of local area network (LAN) in which a supervisory frame, or token, must be received by an attached terminal or workstation before that
  terminal or workstation can start transmitting. Token ring is the technique used by IBM and others.

  UDP (User Datagram Protocol): UDP/IP is a connection-less protocol that describes how messages reach application programs running in the destination machine;
  provides low overhead and fast response and is well suited for high-bandwidth applications.

  Video Conferencing: Video and audio communication between two or more people via a video CODEC (coder/decoder) at either end and linked by digital circuits.

  Voice Mail System: Device or system that records, stores, and retrieves voice messages. The two types of voice mail devices are those which are "stand alone" and those
  which offer some integration with the user's phone system.

  Wi-Fi: A logo granted as the "seal of interoperability" by the Wireless Ethernet Compatibility Alliance (WECA). Only select wireless networking products possess this
  characteristic of IEEE802.11b.

  Wireless AP Support: Access Point functions as a bridge to connect two Ethernet LANs.




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                                                                      Glossary


Wireless Local Area Network (WLAN): A wireless LAN is a data communications system providing wireless peer-to-peer (PC-to-PC, PC-to-hub, or printer-to-hub) and
point-to-point (LAN-to-LAN) connectivity within a building or campus. In place of TP or coaxial wires or optical fiber as used in a conventional LAN, WLANs transmit
and receive data over electromagnetic waves. WLANs perform traditional network communications functions such as file transfer, peripheral sharing, e-mail, and
database access as well as augmenting wired LANs. WLANs must include NICs (adapters) and access points (in-building bridges), and for campus communications
building-to-building (LAN-LAN) bridges.

Wireless Personal Area Network (WPAN): Personal area networks are based on a global specification called Bluetooth which uses radio frequency to transmit voice and
data. Over a short range, this cable-replacement technology wirelessly and transparently synchronizes data across devices and creates access to networks and the Internet.
Bluetooth is ideal for mobile professionals who need to link notebook computers, mobile phones, PDAs, PIMs, and other hand-held devices to do business at home, on
the road, and in the office.

Wireless Wide Area Network (WWAN): Wide area networks utilize digital mobile phone systems to access data and information from any location in the range of a cell
tower connected to a data-enabled network. Using the mobile phone as a modem, a mobile computing device such as a notebook computer, PDA, or a device with a
stand-alone radio card, can receive and send information from a network, your corporate intranet, or the Internet.




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                                 A Few References
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                                 References (cont.)
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ISA Wireless Security, P. Fuhr                                                                                    135
                            Questions?
                                Comments?




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