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Problem Statement for Internet of Things Sensing
draft-hsothers-iotsens-ps-00

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Authors Dirk Von Hugo , Behcet Sarikaya
Last updated 2021-10-18
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draft-hsothers-iotsens-ps-00
Network Working Group                                        D. von Hugo
Internet-Draft                                          Deutsche Telekom
Intended status: Standards Track                             B. Sarikaya
Expires: 21 April 2022                                   18 October 2021

            Problem Statement for Internet of Things Sensing
                      draft-hsothers-iotsens-ps-00

Abstract

   The document attempts to establish hardware based Internet of Things
   authentication as a future networking area beyond 5G going into 6G
   for standardization.  The problem of hardware authentication is
   discussed and its relationship with Wireless Local Area network
   collaborative and/or multi-band sensing is established and then
   recent research efforts in the area are indicated.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

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   This Internet-Draft will expire on 21 April 2022.

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   Copyright (c) 2021 IETF Trust and the persons identified as the
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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Conventions and Terminology . . . . . . . . . . . . . . .   3
   2.  Hardware Based Authentication . . . . . . . . . . . . . . . .   4
   3.  State of the Academic Approaches to IoT Authentication  . . .   5
   4.  IoT Authentication Protocols  . . . . . . . . . . . . . . . .   6
   5.  Hardware IoT Authentication Problem . . . . . . . . . . . . .   6
     5.1.  Architectural and Procedural Issues for Future IP-based
           IoT-Authentication  . . . . . . . . . . . . . . . . . . .   7
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
   8.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   8
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .   8
     9.2.  Informative References  . . . . . . . . . . . . . . . . .   8
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  11

1.  Introduction

   Future networking to make full use of 5G capabilities or even
   resembling an evolution to beyond 5G will have to exploit a much more
   heterogeneous environment in terms of network and device connectivity
   technologies and applications.  In addition ease of use for customers
   and human-independent operation of a multitude of devices and
   machines (things) has to be provided.

   Therefore current authentication models like 802.1X [IEEE802.1X]
   which are based on human intervention do not fit well.  Also this
   model does not scale well for the Internet of Things (IoT).  What we
   need is hardware based admission model.  Such a model will enable
   many new applications as we explain more in this document.

   IEEE 802.11 [IEEE802.11] has a project on Wireless LAN (WLAN sensing)
   and 802.11bf task group (TG) in charge of this project [BFSFD].  Use
   cases for 802.11bf TG includes room sensing, i.e., presence
   detection, counting the number of people in the room, localization of
   active people, audio with user detection, gesture recognition at
   different ranges, device proximity detection, home appliance control.
   There are also health care related use cases like breathing/heart
   rate detection, surveillance of persons of interest, building a 3D
   picture of an environment, as, e.g., in-car sensing for driver
   sleepiness detection [BFUseCases].

   Hardware based authentication that we address in this document builds
   on similar use cases.  We can summarize the use cases we are
   currently considering here: Authenticating the device that is playing
   a melody, or a person has just touched; authenticating devices, i.e.

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   smart teapot with certain manifests, like blinking red and blue;
   authenticate the device when a camera is pointed at it; and the like
   [Henning]. 802.11bf sensing project provides proper framework for
   hardware based authentication because 802.11 or Wi-Fi devices are
   more and more diverse spanning from personal computers, smartphones,
   televisions, tablets, and all sorts of IoT devices or sensors.

   TGbf is also working on Specification Framework Document with an
   outline of each of the functional blocks that will be a part of the
   final amendment like wireless LAN sensing procedure [BFSFD].  TGbf
   sensing is based on obtaining physical Channel State Information
   (CSI) measurements between a transmitter and receiver WLAN nodes,
   called stations (STA).  Using these measurements, presence of
   obstacles between a transmitter and receiver can be detected and
   tracked.  This way, using feature extraction and classification
   provided by means of artificial intelligence (AI), more higher level
   tasks like human activity recognition and object detection are
   available for authentication purposes, while hardware based
   authentication use cases can be achieved through computation of phase
   differences, etc.

   TGbf Wi-Fi Sensing (SENS) is achieved by signaling between just an
   initiator and a responder.  TGbf may also define more effective
   collaborative SENS (in short, CSENS) where multiple SENS-enabled
   devices can collaborate as a group in an orderly fashion to capture
   additional information about the surrounding environment [Rest21].

1.1.  Conventions and Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   Sensing (SENS) is defined as the usage of received Wi-Fi signals from
   a Station (STA) to detect features (i.e., range, velocity, angular,
   motion, presence or proximity, gesture, etc.) of intended targets
   (i.e., object, human, animal, etc.) in a given environment (i.e.,
   house, office, room, vehicle, enterprise, etc.).

   Collaborative sensing (CSENS) defines the operation in which multiple
   SENS enabled devices can collaborate as a group in an orderly fashion
   to capture additional information about the surrounding environment
   and allow for more precise detection, thus enabling a more reliable
   authentication.

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   Multi-band sensing is defined as sensing using both sub-7-GHz Channel
   State Information (CSI) measurements that provide indication of
   relatively large motions and that can propagate through obstacles
   (e.g., walls) and 60-GHz Received Signal Strength Indicator (RSSI)
   measurements at mmWave that provide highly-directional information
   through the usage of beamforming toward a given receiver, but have
   small range due to the presence of blockers (e.g., walls).

2.  Hardware Based Authentication

   Aim of this document is to lay ground for the need for new
   authentication models in the framework of devices (e.g., machines in
   IoT communication) within a (wireless or wireline-based) network.
   Currently employed authentication models (such as e.g., 802.1X
   certificate model) is based on a human being using the machine and
   providing credentials (e.g., user name/password or a permitted
   digital certificate) to the authenticator.  Similarly, for user
   equipment (UE) to access a cellular network the device has to be
   equipped with a USIM and the user has to provide a secret key, i.e.,
   PIN (Personal Identification Number).  With the use case of massive
   IoT (mIoT) as foreseen, e.g., in 5G and with an increasing amount of
   devices within a household (smart home) and/or in the ownership of a
   customer (smart watch etc.) the need for an ease-of-use hardware-
   based admission model arises.

   Focusing on corresponding procedures starting with detection
   (sensing) of a new device and subsequent mutual authenticating of the
   device by and to the network a set of potential technologies are
   identified and described to allow for analysis in terms of criteria
   as reliable operation (working), scalability, ease of use and
   convenience, security, and many more.  Sensing is critical to
   Hardware Based Authentication because sensing (together with
   intelligent interpretation using possibly neural network models) will
   allow the detection of the device playing a melody, blinking red and
   blue, being pointed at, or somebody just touched and the like.
   Furthermore, the method should be applicable to future generations of
   network and of users, upcoming new applications and devices, assuming
   that todays established standard procedures do not fulfill the
   requirements sufficiently.

   Hardware based authentication should leverage collaborative and
   multi-band sensing technologies to enable sensing with much higher
   precision and capacity using the state-of-art equipment.  Also
   equally important is the use of all artificial intelligence and
   neural networks research results developed by the academia.

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3.  State of the Academic Approaches to IoT Authentication

   A detailed review on current topics in IoT Security, Device
   Authentication and Access Control was provided in [Inayat].  The
   following list of literature on sensor data and WiFi sensing for
   securing and authenticating a user and a device shows the wide range
   of approaches and interest in this topic [Rest21].

   [Ma], [Wang], [Zhu], [Wang2], and [Qian] provide a holistic overview
   on the evolution of Wi-Fi technology and on investigations in
   opportunistic applications of Wi-Fi signals for gesture and motion
   detection.

   [Henning2] is investigating geospatial access control for IoT.  There
   are attribute, role and identity based, time based and geospatial
   access control techniques.  Real-world IoT access control policies
   will be a combination of all three, leading to powerful access
   control techniques to use in practice such as in university campus.
   Such access control or authorization techniques will likely be used
   in conjunction with Hardware Based Authentication.

   Other notable literature includes [Al-Qaness] on the so-called
   device-free CSI-based Wi-Fi sensing mechanism, [Pahlavan] using Wi-Fi
   signals for gesture and motion detection as well as for
   authentication and security, [Lui] distinguishing between Line-of-
   Sight (LOS) and Non-Line-of-Sight (NLOS) conditions in case of
   obstacles appearing between the transmitter and the receiver [Guo]
   studying HuAc (Human Activity Recognition) as a combination of WiFi-
   based and Kinect-based activity recognition system, [FURQAN]
   analyzing the wireless sensing and radio environment awareness
   mechanisms, highlighting their vulnerabilities such as dependency of
   sensing modes on external signals, and provides solutions for
   mitigating them, e.g., the different threats to REM (radio
   environment mapping) and its consequences in a vehicular
   communication scenario.

   [Ma2] has studied reliable SENS algorithm for human and animal
   identification.  The aim is to make it resilient to spoofing and
   adverse channel conditions, i.e., presence of noise and interference
   from other technologies.

   [Restuccia] investigates data driven algorithms, neural networks,
   especially convolutional neural network (CNN) or digital signal
   processing (DSP) block to classify complex sensing phenomena.  Also
   [Liao] and [Liao2] proposed to enhance security of industrial
   wireless sensor networks (IWSNs) by neural network based algorithms
   for sensor nodes' authentication and implementations in IWSNs have
   shown that an improved convolution preprocessing neural network

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   (CNN)-based algorithm requires few computing resources and has
   extremely low latency, thus enabling a lightweight multi-node PHY-
   layer authentication.

   Further research on these and similar issues can be found in [Tian],
   [Bai], and [Axente].

4.  IoT Authentication Protocols

   Since IoT applications cover a broad range of domains from smart
   cities, industry, and homes to personal (e.g., wearable) devices,
   including security and privacy sensitive areas as e-health, and can
   reach a huge number of entities the security requirements in terms of
   preventing unauthorized access to data are very high.  Therefore very
   robust authentication mechanisms have to be applied.  At the same
   time depending on the specific scenario a trade-off between resources
   as processing power and memory and security protocol complexity has
   to be considered.  Also a plethora of attack scenarios has to be in
   focus as well as scalability of the considered implicit and explicit
   hardware- and software-based authentication procedures.  [RFC8576]
   serves as a reference for details about IoT specific security
   considerations including the area of authentication and documents
   their specific security challenges, threat models, and possible
   mitigations.

   A more recent work surveys secure bootstrapping and onboarding
   protocols [I-D.irtf-t2trg-secure-bootstrapping-00] developed by IETF
   as well as other standards developing organizations such as IEEE,
   FIDO alliance, Open Connectivity Foundation (OCF), Open Mobile
   Alliance (OMA).

   Lastly, the Open Authorization (OAuth) [RFC6749] protocol in the area
   of authorization is a standard for access delegation.  It extends
   traditional client-server authentication by providing a third party
   client with a token instead of allowing it to use the resource
   owner's credentials to access protected resources while such token
   resembles a different set of credentials than those of the resource
   owner.

5.  Hardware IoT Authentication Problem

   Most of the state-of-art hardware identification techniques to
   authenticate the user use finger prints a.k.a. touch id and facial
   identification and they use detection by hardware i.e. touch,
   accelerometer, and gyro sensors or cameras.  They are based on
   creating a signature, or the user's already stored password [Wang3].

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   On the other hand to authenticate a device based on a set of
   characteristic parameters which should be flexibly chosen by the
   owner and subsequently made known to the authentication system will
   require a certain level of processing and storage capacity either
   within the local system components (e.g., the device itself and the
   wireless point of attachment or access point) and/or within the
   network (e.g., an edge cloud instance or a central data base).  The
   result of the detection process (e.g., radio wave analysis outcome in
   terms of parameters as modulation scheme, number of carriers, and
   fingerprinting) has to be compared with the required (correct)
   parameter values which are safely stored within the network
   components.  On all levels of handling these data, i.e., storage,
   processing, and transport via a communication network, the integrity
   of the content has to be preserved.  One should keep in mind, that
   any unintended authentication request should be prevented to minimize
   the risk of occasional attachment to networks and subsequent exposure
   to attack to sensitive user data.

5.1.  Architectural and Procedural Issues for Future IP-based IoT-
      Authentication

   Here we will discuss possible solutions on IP level and identify
   benefits and potential gaps towards the requirements of next
   generation IoT systems.  On IP or network layer for IPv6 IPsec
   protocol suite is mandatory and provides end-to-end security for
   authentication procedures, ensuring confidentiality and integrity of
   the transmitted data.  Authentication for IoT may rely on a protocol
   as 6LowPAN (Low-power Wireless Personal Area Network) which is
   defined for optimizing the efficient routing of IPv6 packets for
   resource constrained machine- type communication applications.

   When compared to a fully certificate-based authentication, however, a
   hardware-based AAA mechanism relying e.g., on WiFi sensing gesture
   detection does not require the user to know any key, identifier, or
   password for the device to be authenticated.  A pre-defined type of
   access to the device (e.g., physical, photographic or video
   representation, unique description in terms of parameters, etc.)
   shall be sufficient for authentication.

   [RFC8995] on 'Bootstrapping Remote Secure Key Infrastructure' (BRSKI)
   deals with authentication of devices, including sending
   authorizations to the device as to what network they should join, and
   how to authenticate that network by specifying automated
   bootstrapping of an Autonomic Control Plane (ACP).  Secure Key
   Infrastructure (SKI) bootstrapping using manufacturer-installed X.509
   certificates combined with a manufacturer's authorizing service, both
   online and offline, is called the Bootstrapping Remote Secure Key
   Infrastructure (BRSKI) protocol.  Bootstrapping a new device can

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   occur when using a routable address and a cloud service, only link-
   local connectivity, or limited/disconnected networks and includes
   support for deployment models with less stringent security
   requirements.  When the cryptographic identity of the new SKI is
   successfully deployed to the device, completion of bootstrapping is
   achieved.  A locally issued certificate can be deployed to the device
   via the established secure connection as well.

6.  IANA Considerations

   TBD.

7.  Security Considerations

   This document raises no new security concerns but tries to identify
   how to increase security in future IoT by discussing the issues of
   robust but easy to apply authentication mechanisms.

8.  Acknowledgements

   TBD.

9.  References

9.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

9.2.  Informative References

   [Al-Qaness]
              Al-Qaness, M.A.A., Abd Elaziz, M., Kim, S., Ewees, A.A.,
              Abbasi, A.A., Alhaj, Y.A., and A. Hawbani, "Channel State
              Information (CSI) from Pure Communication to Sense and
              Track Human Motion: A Survey", Sensors 2019, 19(15),
              3329 , July 2019.

   [Axente]   Axente, M.-S., Dobre, C., Ciobanu, R.-I., and R.
              Purnichescu-Purtan, "Gait Recognition as an Authentication
              Method for Mobile Devices", Sensors 2020, 20, 4110 , July
              2020.

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   [Bai]      Bai, L., Zhu, L., Liu, J., Choi, J., and W. Zhang,
              "Physical Layer Authentication in Wireless Communication
              Networks: A Survey", Journal of Communications and
              Information Networks Vol.5, No.3, September 2020.

   [BFSFD]    IEEE, "Institute of Electrical and Electronics Engineers,
              IEEE P802.11 - TASK GROUP BF (WLAN SENSING) 11-21/0504r2
              "Specification Framework for TGbf"", July 2021.

   [BFUseCases]
              IEEE, "Institute of Electrical and Electronics Engineers,
              IEEE P802.11 - TASK GROUP BF (WLAN SENSING) 11-20/1712r2
              "WiFi Sensing Use Cases"", January 2021.

   [FURQAN]   Furqan, H.M., Solaija, M.S.J., Tuerkmen, H., and H.
              Arslan, "Wireless Communication, Sensing, and REM: A
              Security Perspective", IEEE Open Journal of the
              Communications Society Vol. 2 , January 2021.

   [Guo]      Guo, L., Wang, L., Liu, J., Zhou, W., and B. Lu, "HuAc:
              Human Activity Recognition Using Crowdsourced WiFi Signals
              and Skeleton Data", Hindawi Wireless Communications and
              Mobile Computing, Volume 2018 , February 2021.

   [Henning]  Schulzrinne, H., "Do We Still Need Wi-Fi in the Era of 5G
              (and 6G)?", February 2021.

   [Henning2] Jan Janak, Luoyao Hao and Henning Schulzrinne, ., "How do
              we program the Internet of Things at scale?", September
              2021.

   [I-D.irtf-t2trg-secure-bootstrapping-00]
              Sethi, M., Sarikaya, B., and D. Garcia-Carrillo, "Secure
              IoT Bootstrapping: A Survey", Work in Progress, Internet-
              Draft, draft-irtf-t2trg-secure-bootstrapping-00, 7 April
              2021, <https://www.ietf.org/archive/id/draft-irtf-t2trg-
              secure-bootstrapping-00.txt>.

   [IEEE802.11]
              IEEE, "IEEE Std. 802.11-2016", December 2016,
              <https://standards.ieee.org/findstds/
              standard/802.11-2016.html>.

   [IEEE802.1X]
              IEEE, "Institute of Electrical and Electronics Engineers,
              "802.1X - Port Based Network Access Control"", January
              2020.

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   [Inayat]   Ali, I., Sabir, S., and Z. Ullah, "Internet of Things
              Security, Device Authentication and Access Control: A
              Review", International Journal of Computer Science and
              Information Security (IJCSIS), Vol. 14, No. 8 , August
              2016.

   [Liao]     Liao, R.-F., Wen, H., Wu, J., Pan, F., Xu, A., Jiang, Y.,
              Xie, F., and M. Cao, "Deep-learning-based physical layer
              authentication for industrial wireless sensor networks",
              Sensors 2019, 19(11), 2440 , May 2019.

   [Liao2]    Liao, R.-F., Wen, H., Wen, H., Xie, F., Pan, F., Pan, F.,
              and F. Xie, "Multiuser Physical Layer Authentication in
              Internet of Things With Data Augmentation", IEEE Internet
              of Things Journal, vol. 7, no. 3, pp. 2077-2088 , March
              2020.

   [Lui]      Liu, J., Wang, L., Fang, J., Guo, L., Lu, B., and L. Shu,
              "Multi-Target Intense Human Motion Analysis and Detection
              Using Channel State Information", Sensors 2018, 18(10),
              3379 , October 2018.

   [Ma]       Ma, Y., Arshad, et al, S., and , "Location-and Person-
              Independent Activity Recognition with WiFi, Deep Neural
              Networks, and Reinforcement Learning,", 2021.

   [Ma2]      Ma, Y. and G. Zhou, et al, "WiFi Sensing with Channel
              State Information: A Survey,", ACM Computing Surveys
              (CSUR), , vol. 52, no. 3, pp. 1-36, 2019.

   [Pahlavan] Pahlavan, K. and P. Krishnamurthy, "Evolution and Impact
              of Wi Fi Technology and Applications: A Historical
              Perspective", Springer Science+Business Media, LLC, part
              of Springer Nature 2020 , November 2020.

   [Qian]     Xian, K. and C. Wu, et al, "Widar: Decimeter-level Passive
              Tracking via Velocity Monitoring with Commodity WiFi,",
              Proc. of ACM MobiCom, , 2017.

   [Rest21]   Restuccia, F., "IEEE 802.11bf: Toward Ubiquitous Wi-Fi
              Sensing", arXiv preprint arXiv:2103.14918 7 pages, March
              2021.

   [Restuccia]
              Restuccia, F. and T. Melodia, "Deep Learning at the
              Physical Layer: System Challenges and Applications to 5G
              and Beyond,", IEEE Communications Magazine, , vol. 58,
              no. 10, pp. 58-64, 2020.

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   [RFC6749]  Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
              RFC 6749, DOI 10.17487/RFC6749, October 2012,
              <https://www.rfc-editor.org/info/rfc6749>.

   [RFC8576]  Garcia-Morchon, O., Kumar, S., and M. Sethi, "Internet of
              Things (IoT) Security: State of the Art and Challenges",
              RFC 8576, DOI 10.17487/RFC8576, April 2019,
              <https://www.rfc-editor.org/info/rfc8576>.

   [RFC8995]  Pritikin, M., Richardson, M., Eckert, T., Behringer, M.,
              and K. Watsen, "Bootstrapping Remote Secure Key
              Infrastructure (BRSKI)", RFC 8995, DOI 10.17487/RFC8995,
              May 2021, <https://www.rfc-editor.org/info/rfc8995>.

   [Tian]     Tian, Q., Lin, Y., Guo, X., Wang, J., AlFarraj, O., and A.
              Tolba, "An Identity Authentication Method of a MIoT Device
              Based on Radio Frequency (RF) Fingerprint Technology",
              Sensors 2020, 20(4), 1213 , February 2020.

   [Wang]     Wang, X. and C. Yang, et al, "TensorBeat: Tensor
              Decomposition for Monitoring Multiperson Breathing Beats
              with Commodity WiFi,", ACM Transactions on Intelligent
              Systems and Technology (TIST), , vol. 9, no. 1, pp. 1-27,
              2017.

   [Wang2]    Wang, X. and C. Yang, et al, "PhaseBeat: Exploiting CSI
              Phase Data for Vital Sign Monitoring with Commodity WiFi
              Devices,", Proc. of IEEE ICDCS, , 2017.

   [Wang3]    Wang, H., Lymberopoulos, D., and J. Liu, "Sensor-Based
              User Authentication", EWSN 2015, LNCS 8965, 168 , 2015.

   [Zhu]      Zhu, H. and F. Xiao, et al, "R-TTWD: Robust device-free
              through-the-wall detection of moving human with WiFi,",
              IEEE Journal on Selected Areas in Communications, ,
              vol. 35, no. 5, pp. 1090-1103, 2017.

Authors' Addresses

   Dirk von Hugo
   Deutsche Telekom
   Deutsche-Telekom-Allee 9
   64295 Darmstadt
   Germany

   Email: Dirk.von-Hugo@telekom.de

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   Behcet Sarikaya

   Email: sarikaya@ieee.org

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