Design and Implementation of Multi Factor Mechanism for Secure Authentication System

(IJCSIS) International Journal of Computer Science and Information Security, Vol. 11, No. 7, July 2013 Design and Implementation of Multi Factor Mechanism for Secure Authentication System Khalid Waleed Hussein #1, Dr. Nor Fazlida Mohd. Sani *2, Professor Dr. Ramlan Mahmod #3 Dr. Mohd. Taufik Abdullah #4 Faculty Computer Science & IT, University Putra Malaysia (UPM) Kuala Lumpur, Malaysia [email protected] [email protected] [email protected] [email protected] Abstract: A secure network depends in part on user authentication and regrettably the authentication systems currently in use are not completely safe. However, the user is not the only party that needs to be authenticated to ensure the security of transactions on the Internet. Existing OTP mechanism cannot guarantee reuse of user's account by an adversary, re-use stolen user's device which is used in the process of authentication, and nonrepudiation. This paper proposed mechanism of multi factor for secure electronic authentication. It intends to authenticate both of user and mobile device and guarantee nonrepudiation, integrity of OTP from obtaining it by an adversary. The proposal can guarantee the user’s credentials by ensuring the user’s authenticity of identity and checking that the mobile device is in the right hands before sending the OTP to the user. This would require each user having a unique phone number and a unique mobile device (unique International Mobile Equipment Identity (IMEI)), in addition to an ID card number. By leveraging existing communication infrastructures, the mechanism would be able to guarantee the safety of electronic authentication, and to confirm that it demonstrates excellence in non-repudiation, authenticate user and mobile device which are used in the process of authentication, certification strength and also in comparison and analysis through experimenting with existing OTP mechanisms. KeywordSecurity, authentication, IMEI, non-repudiation, multi factor 1. INTRODUCTION A credential is a piece of knowledge that enables individual access to computer based information systems[1]. User names and passwords are commonly used by people during a log in process to prove identity[2]. Passwords remain the most common mechanism for user authentication in computer security systems. This has various drawbacks, such as bad choices by users and vulnerability to capture [3],[4],[5]. An additional major problem is the fact that users tend to reuse passwords for different sites [6]. Some studies indicate that more than 70% of phishing activities are designed to steal user names and passwords. According to the anti-phishing working group (APWG)’s report [7], the number of malicious web pages designed to steal users’ credentials at the end of Q2 in 2008 had increased by 258% over the same period in 2007. Therefore, protecting users’ credentials from fraud attacks is extremely important. Many studies have proposed schemes to protect users’ credentials against theft [8],[9],[10]. When a website only uses a user name and password as an authentication method, this method is known as one factor authentication (OFA). Another method is multi factor authentication (MFA). MFA means the use of more than one authentication factor in the authentication process [11],[12],[13]. Mobile authentication is one of the main methods of multi factor authentication. It uses mobile devices 31 http://sites.google.com/site/ijcsis/ ISSN 1947-5500 (IJCSIS) International Journal of Computer Science and Information Security, Vol. 11, No. 7, July 2013 (after install software token on mobile) for multi-factor authentication in place of other authentication methods such as hard tokens, smart tokens or smart chip cards. This requires the installation of software on a mobile device to generate a One Time Password (OTP)[14],[15],[16]. An OTP is a password that is valid for only one login session or transaction. OTPs avoid a number of shortcomings that are associated with traditional authentication (such as usernames and passwords) [17]. Using a mobile device for authentication can be a challenge for the user. Many solutions currently being used by mobile applications either compromise security or usability [18]. There are some common drawbacks of using mobile devices to authenticate users:   element that becomes the basis of certification [23],[24],[25]. Classification Type I Description Example Password, PIN Type II Something you know Something you have Type III Something you are Type IV Something you do Mobile Phone, Token, ID card number Iris, Fingerprint Voice TABLE 1. CLASSIFICATION OF AUTHENTICATION TYPE The user needs to enter a password periodically to start mobile applications [19]. Complex passwords are difficult to enter on mobile devices, and require frequent password entry. As a result of this the user will be compelled either to save the passwords on their devices or choose a weak password that they can easily enter onto their devices When the user’s device is lost or stolen, a criminal can potentially get access to everything stored on the device. This is generally true nowadays for mobile phones and especially smart phones, which now outsell personal computers (PCs). Criminals have exploited this feature by stealing mobile devices and trying to sell them or access the user’s personal information [20], If a user’s device is stolen, the attacker can access the user’s mobile and use it to generate OTPs. Meanwhile the attacker can perform both software attacks and physical attacks against the device. An International Mobile Equipment Identity (IMEI) is a unique number to identify 3rd Generation Partnership Projects (3GPP). The IMEI number is used by a Global System for Mobile Communications (GSM) network to identify valid devices and therefore can be used for preventing access to a network from a stolen phone [21],[22]. In general, methods of certification are considered an essential requirement to authenticate a user when he/she requested service from the service provider, are divided into four, as in Table 1, depending on the 32 An OTP mechanism creates a password only once along with additional features such as user certification and electronic transaction security to protect the user’s information against leakage and at the same time solve the problem of having a static password mechanism. However, for electronic authentication it is not possible to establish face to face communication. In order to confirm the identity of a person accessing the system, the existing OTP mechanism faces problems such as not being able to guarantee certification (the identity of authenticity) and non repudiation [26],[27],[28]. This paper proposes a mechanism to improve the problems of existing OTP authentication and to guarantee certification and non-repudiation of users. The proposed system requires that each user register his or her personal information such as their ID card number, mobile number, IMEI, and PIN into the system. The server should offer this practical service. Server generate a one-time-password by combining the user’s various forms of personal information (as above) and transmitting the created OTP to the user by encoding it after executing an Advanced Encryption Standard (AES) for it. The user registers his or her personal information at the registration phase. During the registration phase the server will verify IMEI validity, with reference to whether there is a valid IMEI number. The user will then transfer to the login phase for authentication by username and password. When the user inserts a correct username and password, the server will transfer the user to a second authentication phase (a new layer) which is known as the confirmation phase. During this phase, the user will be compelled to insert his original personal information that had previously been provided for the system. This http://sites.google.com/site/ijcsis/ ISSN 1947-5500 (IJCSIS) International Journal of Computer Science and Information Security, Vol. 11, No. 7, July 2013 layer combines two factors; something the user knows and something user has, after the user confirms these two factors and submits them to the server. The server will then generate an OTP and send it to the user by encrypted SMS. At this phase the server will verification the IMEI’s validity while simultaneously providing certification guarantee and non repudiation because the OTP will not be sent directly to the user, while the server will check if the mobile device is in the same user's hand or not. This paper is organized in the following order. Chapter 2, which follows the Introduction in Chapter 1 describes the existing research into OTPs, and Chapter 3 discusses secure authentication methods proposed in this research, Chapter 4 describes the experimental environment and the results of comparisons with existing mechanisms. Last but not least, Chapter V describes the conclusion of this research and some possible future research directions. II. RELEVANT STUDIES OTP authentication mechanisms are applied by utilizing various tools such as a hardware device (token device), or a software token (mobile phone) [29]. A. Hardware device (token device) A token device is used to prove the user's identity in electronic authentication. This is done in some commercial transactions or in e-government services like that of New Zealand [30]. It is used in addition to or instead of a static login-ID to prove that the user is who they claim to be. The token acts like an electronic key in order to confirm the identity of a user when he/she is accessing the system[31]. Tokens contain some secret information that can be used to prove identity such as a static password token, a synchronous dynamic password token (The token and the authentication server must have synchronized clocks), and an asynchronous password token (by generating an OTP) [32],[33] ,[1]. A hardware token is considered more secure to use than user ID or passwords. It enhances the image of the organization by securing user credentials more effectively. However, the hardware may cause certain problems such as users always needing to carry the 33 token with them and requiring multiple tokens for multiple websites. This does not provide full protection from man-in-the-middle attacks, and the hardware involves additional costs, such as the cost of the token and any replacement fees [14],[33],[34]. B. Software token (mobile phone) A software token is a form of multi-factor authentication. Software tokens are stored on hardware devices such as mobile phones. Therefore, they are vulnerable to threats such as viruses and software attacks [33]. However, mobile phones are easily lost or stolen, if the mobile phone is in the wrong hands, a criminal can easily use personal data and most of the information is available without a great effort through services such as SMS [35]. Researchers try to solve the problems of security of authentication either by utilizing mobile phones as software tokens to generate an OTP which is then sent to the server[15],[36], or by using mobile phones as tools to receive an OTP from servers through SMS. In this case the system requires that the users log in to the system with a username and password and by correctly inserting credentials. Then the OTP code will be sent by mobile phone via SMS [37]. In both cases (the mobile phone as soft token and using a mobile phone just for receiving SMS) the authentication systems suffer from not guaranteeing the user’s certification and non-repudiation [26],[27]. III. PROPOSED SYSTEM By leveraging existing communication infrastructures, no additional costs are required for the proposed system. In any system of processing of electronic authentication, the identity, authenticity and non-repudiation of transactions are particularly important [38]. This paper resolved the problem of non repudiation during the authentication process and will contribute to the increased security of multi factor authentication process by sending the OTP only to trusted users. A. Registration Phase In the registration phase users are compelled to use their personal information (username, password, a 4-6 http://sites.google.com/site/ijcsis/ ISSN 1947-5500 (IJCSIS) International Journal of Computer Science and Information Security, Vol. 11, No. 7, July 2013 digit PIN, email, ID card number, and mobile number) in addition to International Mobile Equipment Identity (IMEI). Some algorithms will check IMEI for the user’s mobile phone. If the IMEI not real, the user will be prevented from becoming registered in the system (system not safe wrong data). Thus the user is compelled to insert a real IMEI in the registration phase. Also, if IMEI and the mobile number are repeated (when registered by another user) the user will not able to complete his or her registration. The use of this method will ensure that every user has one mobile number and one IMEI number in addition to their ID card number. Mostly, authentication systems which are users of OTP authentication allow users to possess many accounts with the same mobile number. This will not happen in the proposed system, which will work to control the management of users’ accounts and to reduce the errors in the users’ information in the database. After the user is successfully registered, they will transfer to the login phase. B. Traditional Login Phase In this stage user will login into the system by using his username and password, if user insert wrong credentials (username and password) he will not able to accessing as in traditional login phase and he will still in this phase till insert correct one. After the user inserts a correct username and password as he or she enters the registration phase, the system will transfer the second user authentication phase (New layer of authentication). C. New Layer (Confirmation Phase) The creation of this layer will prevent the generation of the OTP by the server and prevent it being sent to user until the user confirms his or her personal information (PIN, mobile number, IMEI) which was registered in the previous phase (registration phase). Also, this layer will ensure the identity of authenticity and realize non-repudiation. In other authentication systems, after users submitted their credentials (username and password) to the system they can receive OTPs directly from the server by SMS. The proposed system will not generate OTPs and will not send anything to the user until the system ensures that the mobile device is in the right hand (in the hand of same user who request authentication). In this way the system will ensure the liability of the person that 34 misuses the system. This layer combines two factors; something the user knows (PIN) and something user has (mobile number and IMEI). Applying this in one layer to confirm the identity of the user is considered a new idea. Also, at this point the user can choose a method of receiving the OTP. If the user prefers not to receive the OTP by SMS he or she can receive it by email. Thus, in this layer the user will choose the method of receiving the OTP depending on what he prefers. If the user prefers to receive OTP by email, he demands to enter his email, PIN, and ID card number. In both cases (when the user prefers to receive OTP by SMS or by email) the user will receive an encrypted OTP by using Rijndael AES 256 and the decryption of the OTP will be conducted by PIN, which is a symmetric key between the user and the server. In case the user inserts the wrong information in confirmation phase server will redirect the user to the first login (traditional login) and the process of authentication will begin again. If an adversary try to impersonate legal user shall get all user’s information such as username and password (to pass from first login), steal user’s mobile phone (to pass from confirmation phase and receive SMS), user’s ID card number, user’s email (username and password to access email), and PIN which is required in confirmation phase and for decrypt SMS or email. D. Generating & Sending OTP After the user passes through the confirmation phase, which will deal with the user reliably, the server will generate an OTP from the user’s information. This may happen in two ways. The user may prefer to receive the OTP by mobile phone or may prefer to receive OTP by e-mail. This means that if users prefer to use mobile phones to receive OTPs, the elements which are demanded from user at the confirmation phase will contribute to the generation of OTP and the elements which are required from the user in the confirmation phase when he or she intends to receive OTP by email will contribute to the generation of OTP. In this way the future OTP cannot be predicated because the OTP will be totally different from one user to another. Also the OTP will be taken randomly from the user’s info, so that the user will not get the same OTP when he or she uses the proposed system. In this paper the processes of Multi Factor Mechanism for http://sites.google.com/site/ijcsis/ ISSN 1947-5500 (IJCSIS) International Journal of Computer Science and Information Security, Vol. 11, No. 7, July 2013 Secure Authentication System are shown in the Figure1. Non-repudiation: Because the proposed mechanism works to authenticate the user and his or her mobile phone (IMEI plus mobile number), so the proposed system has all important information about the user such as ID card number, mobile number, and IMEI, all of which are unique. Thus the proposed system can ensure the liability of the person that misuses the system. Long term password: A long password for authentication is generally considered to be more safe than a short one. However, humans have difficulty remembering complex or meaningless passwords [39]. At the confirmation phase, the user needs only to rewrite long term passwords such as (IMEI, the mobile number, or the ID card number) which they are already possess, or he/she can take it from his/her ID card or mobile phone, while the other system needs the user to remember these details. Tracking user: Most authentication systems which generate OTP through the server and send the OTP to user by SMS cannot track whether the user is tampering with system because the authentication system only has the user’s mobile number, in addition to their username and password. Thus a criminal could tamper with the system by receiving OTP through SMS and could then change or throw away the SIM card. While the proposed system can determine the Fig. 1. Procedure of Proposed System The server will send the encrypted OTP in the manner favoured by the user (SMS or email). After the user receives an encrypted message by OTP, he or she will transfer to another screen to prove the validity of his PIN and at the same time to decrypt the OTP (a symmetric key for encryption and decryption). If the PIN is wrong the session will end. IV. COMPARISION ANALYSIS A. Comparison and Analysis In order to conduct a performance analysis of the proposed mechanism and the existing mechanism, comparison and analysis were executed on totally 8 performance evaluation elements such as non repudiation, long term password, tracking user, the block user’s mobile phone, authenticated user and mobile phone, users’ information reuse prevention, cell phone reuse prevention, and certification type. 35 liability of the person that misuses or tampering with system by using user's ID card number (unique number), in addition of mobile number (every user has unique mobile number and unique IMEI). Block user’s mobile: An International Mobile Equipment Identity (IMEI) is a unique number used by a Global System for Mobile Communications (GSM) network to identify valid devices. An IMEI can determine the position of a mobile device and also can blacklisting the device so that it becomes unusable on any network. The proposed system requires inserts in the IMEI to authenticate the user’s device and to taking the necessary precautions in the event of tampering with the system. If the administrator of the proposed system discovers any attempts to tamper with the system he will be able to cancel the user's account and block the user and his or her mobile device from registering in the system. While an existing OTP system cannot prevent the use of the same device, the illegal user can return to register himself (if the http://sites.google.com/site/ijcsis/ ISSN 1947-5500 (IJCSIS) International Journal of Computer Science and Information Security, Vol. 11, No. 7, July 2013 administrator discovers illegal attempts being carried out by the user) as a legal user to access the system. Authenticating users & mobile phones: Compared with other authentication systems which utilize mobile phone to generate OTPs or for receive SMS, these systems attempt to authenticate the user and neglect other parties which are used in the process of electronic authentication such as the user’s mobile phone. However, the user is not the only party that needs to be authenticated to ensure the security of transactions on the Internet [40]. The proposed system works to authenticate both the user and mobile device, in addition to mutual authentication between the user and the server through a Secure Socket Layer (SSL). User’s information Reuse Prevention: The proposed system achieves a one-time password approach. Every user has totally unique information, which means there should be no need to separate the data as in other systems. This enhances privacy protection and minimises the probability of data matching. can ensure the liability of the user that misuses the system. This mechanism requires the users presenting more information to prove proof their identity (in order to prove to the system that this user is the same user with the same device which is already registered in the system) unlike existing methods (such as utilizing the user's mobile phone to receive OTPs). Therefore the proposed method is suitable for areas in which security is crucial, such as providing authentication for internet banking, authentication for electronic payment, electronic governments authentication, and cloud computing authentication. REFERENCES [ 1] [2] [3] Cellphone Reuse Prevention: The proposed system can prevent the cell phone from reuse by a criminal because the proposed system requires that every user has a unique phone number and a unique mobile device (IMEI), while indicating that the user’s cell phone be lost or stolen. The attacker cannot use this by accessing system till gets other elements such as user’s PIN or user’s ID card number for the pass confirmation phase. Certification type: Existing methods which utilize the user’s mobile phone to receive SMS or to generate OTPs rely on what the user knows, while the proposed system depends on a combination of two factors - what the user knows and what the user owns (IMEI), In addition this method uses a new way to authenticate the use of a cell phone. It also works enhances security and operates as multi factor authentication inside multi factor authentication (nested multi factor authentication). [4] [5] [6] [7] [8] [9] [10] [11] V. CONCLUSION [12] This paper proposed a mechanism of action for OTP authentication which can reinforce the security of authentication and the mechanism of guaranteeing nonrepudiation by authenticating the user and the device which is used to receive encrypt OTPs. 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