UBIQUITOUS COMPUTING FOR SECURITY ENHANCEMENT OF VEHICLES Nor Azlina Bt Abd Rahman Asia Pacific University College of Technology and Innovation Kuala Lumpur, Malaysia
Mohsen Bafandehkar Asia Pacific University College of Technology and Innovation Kuala Lumpur, Malaysia
Behzad Nazarbakhsh Asia Pacific University College of Technology and Innovation Kuala Lumpur, Malaysia
[email protected]
[email protected]
[email protected]
Abstracts: This paper shows how ubiquitous computing can be applied to intensify the security system of vehicles. Some ubiquitous elements are being discuss which include communication technologies such as Bluetooth, Infrared, Wi-Fi and UWB, automatic Identification and data capture (AIDC) such as RFID, virtual barcodes, biometric, smart cards and OCR, authentication methods such as passwords, one time passwords etc and ubiquitous system devices such as tabs, pads and boards. The key features which affect the decision for choosing the best communication method and technology are also discussed. Keywords: vehicles, security, ubiquitous computing, virtual barcodes, RFID, smart cards, OCR, AIDC
I.
INTRODUCTION
Automobile industries have been experiencing a faster rate of growth nowadays. As the number of automobile shows the increasing every year, the same thing goes to the motor vehicles theft cases. As the result, the anti-theft system become demanding among the owners of the vehicles. The vehicle anti-theft technologies are being improved during decades but the current technologies are not accurate. Most of the anti-theft technologies are mechanical devices that cannot check authentication of vehicle’s owner. There are many tools available to gain entry into locked vehicles such as picklock. Bringing awareness to anti-theft technologies will help to solve most of motor vehicles theft problems. As Ubiquitous computing environments will not only provide new technologies for us to interact with; they will significantly affect our interactions with objects. The main goals of ubiquitous computing are bringing intelligence to objects, nods or environment, so that the security would simultaneously be increased. Identification, location and sensing are the elements of devices, objects/nodes in a ubiquitous computing [4]. In order to make objects and devices useful as a part of an intelligent, the objects that surround us can become resources and act as interfaces to other resources. Information about location is another ability of objects and devices which bring another important level of intelligence in ubiquitous computing. Adding up a sensing capability for collecting a range of data and responding to events simultaneously would bring new vision of intelligence for enhancing authentication.
978-1-4577-0577-9/11/$26.00 ©2011 IEEE
Nurul Haniza Bt Mohtar Asia Pacific University College of Technology and Innovation Kuala Lumpur, Malaysia
[email protected]
The intelligence which are providing for each system through different software or electronic tools will inform or alert a user, as a result, the system will be able to make decisions. Consequently, authentication and security will be augmented according to boundary of decisions area of objects [4]. II.
COMMUNICATION
The primary key of growing the vehicles security is bringing communication between owner and motor car. Communication with the motor cars will be divided in to two types, intra-vehicle and inter-vehicle communication [5]. Intra-vehicle communications occur within a vehicle atmosphere but the inter-vehicle communications represents communications between vehicles and Sensors/Electronic devices placed in environment. Communications media are categorized into wire and wireless. The important keys of communication in any form are [27]: x Maximum communication range x
Propagation within crowded environments
Radio signals at lower frequencies propagate farther than signals at higher frequencies (assuming similar transmitter power levels) and the attenuation of a radio signal as it travels through a medium related to its wavelength [6]. The signals at lower frequencies have longer wavelengths and consequently signal attenuation occurs at a slower rate. In the other hand communication range and propagation are directly related to the wavelength and frequency of signal. The signal-to-noise (S/N) ratio will be used to categorize the quality of communications transmission. (Measured in decibels db) The S/N ratio is defined as the ratio of the signal power (S) divided by the noise power (N) on a transmission medium [5]. Wireless communication technologies are required to connect “smart things” with each other regardless of where they are located. Typically, a broadcast medium is used as a basic communication scheme. It is possible to use infrared and radio waves for communicating with the vehicles [5]. Very High Frequency (VHF) and microwaves are a type of broadcast communication while infrared and millimetre waves are a type
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of directional communication. The key features which affect the decision for choosing the best communication method and technology are [13]: x Quick detection of all devices. x
Ability to detect all kinds of ubiquitous devices especially popular one.
• IEEE 802.15.2: Coexistence • IEEE 802.15.3: High rate WPANs (HRWPAN), UWB • IEEE 802.15.4: Low rate WPANs (LRWPAN), ZigBee • IEEE 802.15.5: Mesh network
x
No need for pre-installing any additional hardware or software to a mobile device.
x
The users should be able to easily receive the messages and read them.
It is possible to use Bluetooth to set up the reliable Communication. Bluetooth is cheap technology. It can transmit voice and data, and has a large data frame payload. It also has low power requirements and can penetrate obstacles such as walls. It has a large installed base and a guaranteed latency, as well as a stable specification [28]. An alternative to Bluetooth is a new radio frequency technique called Ultra Wideband (UWB). UWB has the wideband nature of the signal. The main advantages of UWB technology are its high data rate, low cost, and immunity to interference [29]. ISO TC204/WG16 has produced a series of draft standards known as CALM. The goal of CALM is combining General Packet Radio Service (GPRS) with vehicle-optimized WLAN technology. It has the cooperation of IEEE 802.11p and P1609 - Wireless Access in the Vehicular Environment.
• IEEE 802.15.6: Body area network technologies TECHNOLOGIES & CONTEXT-AWARENESS SYSTEM There are three fundamental forms for ubiquitous system devices [8]: x Tabs: wearable centimetre sized devices III.
Vehicular environments required a wireless personal area Network (WPAN) because a driver is a master for the vehicle [30]. The driver interacts with his/her vehicle according to the collected information from WPAN and a controller area network (CAN). The standard of WPANs is defined in the15th working group of the IEEE 802.15. There are six task groups in the working group as shown in the following. • IEEE 802.15.1: Bluetooth
Pads: hand-held decimetre-sized devices
x
Boards: meter sized interactive display devices.
These three proposed by Weiser are characterised by being micro-sized, having a planar form and on incorporating visual output displays but this range of devises could be expended into a various and practical range of Ubiquitous Computing devices. Three additional forms of ubiquitous systems could be developed [8]: x Dust: miniaturised devices can be without visual output displays, e.g., Micro Electro-Mechanical Systems (MEMS), ranging from nanometres through micrometers to millimetres.
IrDA is a low cost technology used for many purposes. Most common usage of IrDA is the short distance communication of devices for exchanging data, by remote control device. The technology requires a line of sight between communicating devices for them to be able to exchange data [31].There are several sources of interference that can affect IrDA and it is disadvantageous of this technology for instance light can be affected by other light sources and electromagnetic fields. 802.11b (Wi-Fi) is a wireless technology operating in the 2.4GHz zone. It is used for connecting high power devices like computers, laptops and PDAs. The connection speeds are much higher than IrDA’s or Bluetooth’s, as well as the range of the connection.
x
x
Skin: fabrics based upon light emitting and conductive polymers, organic computer devices, can be formed into more flexible non-planar display surfaces and products
x
Clay: ensembles of MEMS can be formed into arbitrary three dimensional shapes as artefacts resembling many different kinds of physical objects
Communicating through those system devices will be the key to the development of ubiquitous. ‘If objects were capable to answer, Who are you? (identification), Where are you? (localization) and What are you doing? (monitoring), the identity of an entity automatically will be acknowledged. Security properties which are sound important to be applied in vehicle safety are [9]: x Confidentiality: Secrecy of communication between parties. x
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Integrity: assurance that data has not been modified by an unauthorized party.
x
Authenticity: assurance that a message originated from a known other party.
x
Identification: determination of a contextually unique label for a party.
x
Access Control: limitations on exposure or modification of protected resources to authorized parties.
x
Availability: a service or system performs its function in a timely manner for legitimate users.
x
Audit ability: logging of security-relevant actions or events for later analysis. Many attacks cannot be reliably detected in real-time, but can be analysed after the fact to help with future defenses. Below are currently used methods for authentication [14]. x Passwords: Combination of characters that can be used for login. x
One-time passwords: The Passwords which are used one time in an application or generated by a hardware device.
x
Challenge response: A challenge generated by a server is sent to the user calculates a response and sends it back.
x
Biometrics: Proves a user’s identity by physical features of the user,
x
Location based: A user located in a specific area is authorized based on Such as GPS
x
Two-factor authentication: Combination of more than one authentication methods which are defined above.
A main in establishing a sense of security is how to express the basic security properties to the user. The Pervasive computing systems could be used as the part of ubiquitous computing security [13]. It is capable of monitoring predicting and reacting to real world condition. Theft Prediction is possible with Auto-ID because it help to recognize patterns in real time and trigger deterrence measures [7]. Consequently Auto-ID is pondered to provide unique intelligent capabilities as the part of pervasive computing to combat theft. AIDC (Automatic Identification and data capture) is a collective of ubiquitous system devices that capture or collect data using automated mechanism without the need for manual input [6].The purpose of AIDC is identity management, for solving the problem of having many passwords and usernames to remember and also simplifying the access of user to system with proper security.
Figure1. The poster ‘Over view of AIDC‘ ‘AIDC comprises two tasks which are capturing an external stimulus or signal and recognizing that signal by a computer analyses. There are five focal types of AIDC systems which are Barcode System, Optical Character Recognition (OCR), Biometric, Smart Card and RFID [6]. A. RFID RFID is an important technology from the point of view of ubiquitous computing. In RFID Technologies, data on RFID tags can be read by a wireless transceiver and the data passed back to computer systems. Two main types of RFID tags are passive and Active. Table 1 shows the differences of these two RFID tags [11]. TABLE1. Passive vs. Active RFID tag Items Comm.Range Battery life Security Cost Application
Passive RFID tag 70cm/ 3m - 7m No battery Weak Less than1 $ Distribution/controlling
Active RFID tag more than 10m Around 1 year Strong Around10 $ Tracking objects with no restriction
The range of the conventional active tag’s communication should be longer compared with a passive tag because it incorporates a battery [11]. Furthermore the area which is applied with active tag should be in a safe area because it has a security issue. The passive tag will sends a radio signal only when it is activated by the reader. Therefore, no unnecessary radio signal is transmitted. Unfortunately, anyone with an appropriately equipped reader and close access to the RFID device can activate it and read its contents. However RFID tags will be affected by metals and liquid [6]. Early research has invented that Generation 2, known as Gen 2 UHF tags have overcome those problems and also will not be affected by ultra high frequency waves. The main advantageous of this tag is permitting near-field reading, in which the reader is close to the tag being read, in addition to far-field reading of tags [6]. When transmitting in a near-field situation, the UHF tags transmit through the magnetic field; when transmitting in a far-field situation, the UHF tags transmit through the electromagnetic field. However the risk of UHF tag is more serious because it has a longer communication range. When the communication range
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becomes longer, the convenience in operation improves. But providing security for that will be more complicated. The LANDMARC system uses RFID for locating the position of the User indoors [16]. But some problems were pointed out regarding the efficiency of the RFID technology that being used in location sensing: x None of the currently available RFID products provides the signal strength of tags directly. x
The long time interval of emitting two consecutive IDs from an active tag.
Base on table2 above, the 2D barcodes are approximately performed as same as the RFID but the cost of 2D barcodes per unit will be reduced and as the result it uses more than RFID [15]. Ubicode was introduced as a location limited method of transferring data from one node to another.’ This method uses the display of one device and a digital camera attached to another device to transfer information via a twodimensional barcode.’ Visual barcode and augmented reality will provide another practical method for enhancing securities of vehicle. Figure3 describes the augmented reality which is suggested for E-learning system [15]. In this system, the mobile device is introduced as device for monitoring information.
x the variation of the behaviour of tags Consequently, if all those problems could be overcome, RFID technology will be a very competitive technology. RFID could be used to keep track of whether the object is available, in use, or undergoing. The intelligent immobilizing system was proposed by Seri Lanka university (2007, p.441) used RFID technology. It makes capable an active communication path between the vehicle and the owner .Moreover it enables the vehicle owner to immobilize the vehicle.
Figure3. ’The context-aware scenario’ In order to this proposed educational system and the Ubicode method concept, monitoring and controlling the vehicles will be possible with transmitting data by mobile devices [15].
Figure2.’ Basic operating structure of immobilization System’ Base on immobilization System above, integration of UHF tags, the vehicle tracking and controlling will be possible. In the other hand RFID tags can operate without user intervention and also provide data, which creates a need for more sophisticated systems to support them. Without doubt RFID tags improve certain security properties. The small size of RFID chips (as small as 0.05 mm2) could provide seals of authenticity in forgery with high probability of misleading the hijackers, tracking and controlling the vehicle. B. Visual barcodes The main advantageous of 2D barcodes are bringing ability of managing by the client on the devices. TABLE2. RFID vs. 2D barcode Characteristics Positioning Accuracy Context awareness Sensor Technology Cost Cover Area Practicability
RFID High High Auto High Micro High
2D barcode High Middle Passive Low Micro High
C. Smart card It has been shown that a smart card makes a perfect intelligent token for enhancing systems security. It has capability of selfprocessing and data storing. Smart cards can either be contacttype cards or contactless-type cards. Contact cards require a physical contact between the card and the reeded / writer unit. But Contactless-type cards have the following characteristics [20]: x Close-in or long range x
Electromagnetic and Capacitive
x
More reliable
x All-one-chip-solution The concept of digital signature scheme used in authentication comes from smartcard. Smart cards contain capabilities of identification, authentication and electronic signature [22]. The digital signature will provide authentication and protection of information. Smart Cards will bring the below privacy in ubiquitous environment which are Account verification, User identity verification, Information access restriction and Prevention of card tampering. Account verification, information access restriction and prevention of tampering are very critical in contact less smart cards because the card is open to abuse and it is necessary to address security implications at all levels of card's life cycle [20].
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The proposed E-voting system is illustrated each voting machine is equipped with a contactless IC card reader and each legal votes will be issues with a contactless IC card at polling place. Some personal information will be written on IC cards. The system would produce a random number on the ballot card that is not only used to preventing faking cards, but also used as a verifying code at the voting centre. Figure4 below, illustrates how smart card could be used as the AIDC technology for authentication and enhancing security [21]. It is considered that for authenticating vehicle’s owner before mobilization applying that method by smart cards for holder’s identifying is sound useful and possible in real world.
Figure4.’ Illustration of the proposed E-Voting System D. Optical Character Recognition (OCR) The infrastructure for pervasive computing should support context awareness by facilitating the gathering of information from sources such as sensors and resource monitors [23]. Special characters that understandable both humans and machines for presenting a series of unique codes calls character recognition. Performing interpretation of data and carrying out distribution of contextual information to interested parties in a scalable approach are the main reason of using OCR [6]. OCR Technology uses the line of sight within a short distance to read the label and it is the main disadvantageous of that. Below schemes could be used by OCR for tracking, tagging and controlling objects [6]. x Video Metric: The position and orientation of the target is computed in three dimensional through the sensor(s). x
Beam Scanning: Sensors located on the target detect the time of sweep of the beams on their surface and scan optical beams.
x
Phase Difference: This technology will measure the relative phase of an incoming signal from a target and a comparison signal of the same frequency located on the reference.
x
Motes: A development of sensor involves nanosensor. These ‘smart dust’ is robust because it can be sprayed into an environment or on an object [4].
According to those current schemes which are available today attaching sensors or Micro Electro-mechanical Systems to RFID tags may be used to bring the sense in to the environment and allowing object respond to the real world without human intervention. Optical character recognition system will bring awareness in the ubiquitous environment with real time detecting and responding by tracking, monitoring and detection [4]. E. Biometric There are many ways that human interact with objects. Behavioural biometrics is one of those developing field [24]. People tend to operate vehicles in very different ways, some drivers are safe and slow, and others are much more aggressive and often speed and tailgate. As a result, driving behaviour can be successfully treated as a behavioural biometric. Behavioral technology has great advantages to use such as variability, stability and security [25]. This proves to be very propitious for high security environments. Using the wearable computing technologies will help to pick up the electrical signals which are produced by various regions of the heart during the pumping cycle; it is supposed that the identity of each person will be recognized by ECG technology because each individual person has the unique electronically signals [24]. Consequently, the gesture recognition proposed the following gesture taxonomy for communicating with computers [26]: x Symbolic gestures: gesture which have a single meaning. x
Deictic gestures: It is the gestures of pointing for directing the listener’s attention to specific events or objects in the environment.
x
Iconic gestures: These gestures are used to express information about the size, shape or orientation of the object of discourse.
x
Pantomimic gestures: it used in showing the use of movement of some invisible tool or object in the speaker’s hand. As a final point, Biometric recognition would bring new vision of security in ubiquitous computing in near future. Using embedded computing system with biometric technology supposed to secure robustly the objects and environment. As the result, the level of complicity of accessing data will be increased, Authentication and privacy will be more precise, accurate and secured but beside all of those the intricacy of implementing the technology will be increased. IV. CONCLUSIONS Ubiquitous computing brings new challenges to security and privacy, which cannot be thought as afterthoughts. Generally, the realization of the security vision is a research field with various open problems. In this paper many of the existing technologies and security key words were evaluated and
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discussed regarding their relevance to future Ubiquitous Computing environments. Furthermore existing concepts in ubiquitous computing and their relationship of those technologies for enhancing the privacy and security of vehicles in ubiquitous environments are studied. The vision of future Ubiquitous Computing for enhancing vehicle security that will be provided by embedded systems, due attention to current technologies are discussed. Finally, the concept of enhancing security with using of the high numbers of devices that form Ubiquitous computing environments and importance of their context awareness level are studied and discussed. REFERENCES/BIBLIOGRAPHY [1]
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