BR102015027719A2 - security method for user authentication via public telephony using dtmf signal - Google Patents

Abstract

security method for user authentication via public telephony using dtmf signal. A transparent token is generated on the user's mobile device (smartphone) from a security calculation that uses otp token generated from otp seed and device id information, and is sent to the public telephone network via signals. dtmf. In the service provider there is an authentication server that validates the transparent token received from the user. The method is proposed to be used through phone calls originating from cell phone. With its use, there is no need for direct user-device interaction, as well as no need for the user to carry additional devices such as a keychain token or a security card. The transparent token, calculated from an otp token and a device id, provides a higher level of security compared to a traditional otp token.

Description

“SECURITY METHOD FOR USER AUTHENTICATION BY PUBLIC TELEPHONY USING DTMF SIGNAL” PRESENTATION AND FIELD OF THE INVENTION

[0001] The present invention applies to the development of a security method for transparent authentication in order to improve user security and usability in accessing services via voice and public telephony channels. A transparent loken is generated on the user's device (smartphone) from a security calculation that uses OTP seed and mobile device ID (Device ID) information and is sent to the public telephone network via DTMF signals. At the service provider, there is an authentication server that validates the transparent token received from the user. The method is proposed to be used through telephone calls originating from cell phones.

Using the transparent token reduces the risk of fraud and facilitates user access to voice channel services compared to traditional authentication methods such as verification questions or security codes. Using it, there is no need for direct user-device interaction, and no need for the user to carry additional devices such as a keychain token or security card.

The transparent token, calculated from an OTP token and a Mobile Device DD (Device ID), provides a higher level of security compared to a traditional OTP token.

TERMINOLOGIES

For better understanding of this patent application it is urgent to define some acronyms, expressions and terms used throughout this description: CALLER ID SPOOFING - Fraud with alteration of the telephone number that originates the call. DEVICE ID - Element that uniquely identifies the mobile device. DTMF - Dual Tone Multi Frequency - Frequency used in fixed telephony for information transmission. HASH - Cryptography Algorithm - Hash Algorithm. HTTP - HyperText Transport Protocol - A transfer protocol between information systems that allows data transfer between computer networks. KBA - Knowledge Based Authentication - Authentication method in which the authenticated user must know the answers to specific questions. OOB - Out Of Band - Exchange information on a separate dedicated channel. OTP - One Time Password - One Time Password. PHISHING - Online fraud technique for stealing passwords and personal data. PHARMING - Evolution of online fraud technique for theft of passwords and personal data. PIN - Personal Identification Number. PROXY - Intermediate server between users and other servers. YES - Subscriber Identity Module - Subscriber Identification Module. SMS - Short Message Service - Message service via mobile device. SNIFFING - Tool used to intercept and data on a computer network. IVR - Audible Response Unit - Used in call centers. VoIP - Voice over IP - Voice over Internet Protocol.

THEORETICAL CONVENTION

In general, a communication network is a geographically distributed set of interconnected subnets for transporting data, for example, voice signals, between nodes, such as intermediate nodes and end nodes. As an example of us end we have phones, servers, mobile devices and personal computers. Nodes communicate normally through data exchange according to predefined protocols. In this context, a protocol consists of a set of rules that determine how nodes interact with each other.

Authentication is required in order to provide secure user access to a remote service, such as an online or telephone system, or to a local service. However, common authentication processes can be stressful for the user when requesting a service over the telephone, where they are required to respond to numerous requests for passwords and / or personal data, and such requests may have to be repeated when This user is passed to another attendant during the same call. The user may need passwords that are difficult to remember, and these passwords may also be intercepted, and the user's personal data may be illegally obtained through other means.

[0007] Authentication is intended to validate a particular identity, which may be the user, device or transaction. Authentication can be based on factors: something the user knows, something the user has, or something the user is. Each authentication method has a function against a variety of different attacks against authentication systems. Attacks against authentication systems are intended to gain access to a particular service in an unlawful manner, with impersonation (user or device).

[0008] One of the attacks, known as a replay attack, reuses an access credential on subsequent access.

Another problem is the use of passwords as an access credential. Passwords can be stolen, discovered, guessed or broken.

The use of multifactor authentication makes attacks more difficult to carry out.

Use of technical resources promotes user authentication more securely, with a number of attacks against authentication being avoided, such as using an OTP token, which is a one-time password.

[0012] The OTP token is normally inserted by the user himself, which makes the transparent token, which is automatically used in the authentication process, more secure in this direct comparison.

[0013] There are some attack scenarios that analyze transparent token approaches with traditional OTP token approaches, including: [0014] Brute force: The attacker has limited time to perform the attack, as both the transparent and the token OTP token have a time-based validity, traditionally 30 seconds. Given its use in a voice phone channel, the scope for the success of this attack is low, as a certain number of transparent token or OTP token can be tested only once for each telephone call.

Simultaneous telephone calls: The attacker can obtain a set of mobile devices to make simultaneous calls that enter different values of transparent tokens or OTP tokens. Similar to brute force attack, there is a limit on the token's validity time. However, the attacker in this case has the possibility of making the attack faster with parallelization. However, using the 08-digit token would require the attacker to use 100,000,000 simultaneous mobile devices to authenticate an access within the transparent token or OTP token available time-frame (traditionally 30 seconds). In addition, the attacker would have to falsify the Caller ID Spoofing if the service provider performs this verification of the origin of the telephone call.

Theft of the OTP seed and Mobile Device ID during transmission: The attacker could use the victim's OTP seed to perform an illicit access. In the case of the traditional OTP token, the attacker must obtain the OTP seed at the moment of its transmission to the user. In the case of the transparent token, the attacker must also have access to the Device ID at the moment it is sent to the server.

[0017] OTP seed and mobile device ID theft directly on the user's device: The attacker could infect the user's device with malware and illegally obtain both the OTP seed and the mobile device ID. (Device ID). There are techniques like data obfuscation to make this attack difficult.

[0018] To overcome the problem of fraudulent access to business and conference phone systems includes requiring authorized users to sign in with a personal identification number (PIN). Mechanisms for validating caller ID are also widely used. Tools commonly used by hackers to compromise user passwords and network security include sniffing (in which hackers steal passwords transmitted over wireless networks). In addition, a caller ID can be entirely spoofed without much difficulty on a public telephone network.

A variety of security protocols and algorithms have been developed to address the need to authenticate users attempting to access services.

To alleviate this problem and minimize the risk of this threat, some institutions have shifted to deploying single token, multifactor authentication solutions and using cryptographic token multifactor or single-use multifactor password devices. Such solutions, which are well known in the art, have so far costly and complex card or signal distribution systems to end users. In the multifactor and multifactor cryptographic token of single-password solutions, these deployments face additional challenges as proper application requires a device cryptographic key release based on the use of a password associated with that device. Such devices are expensive, and implementations are time consuming and logistically complicated to implement and manage especially for heterogeneous large-scale user bases.

[0021] The present invention relates to a method and system of security authentication by asserting electronic identity with very high telephony-focused reliability, with authentication occurring transparently via DTMF telephone signal.

DESCRIPTION OF TECHNICAL STATE

[0022] In traditional methods of authenticating users who use services via public telephony (voice channel), there is user interaction with their device or attendant to send information that validates their identity.

Some traditional authentication methods performed when a voice channel is used are: Passwords: The user dials a password on their device (landline or mobile), which is sent to the service provider via DTMF (Dual Signal) signal. TONE Multi Frequency). An audible response unit (IVR) translates this DTMF signal to values that are compared on the authentication server.

[0025] Token: Also known as OTP (One Time Password), has valid values for single use only. One way is for the user to have a security card that corresponds to a table with values in a series of positions that the user must dial on their device, according to the requested position. OTP can also exist on a physical device (such as a keychain), or software on the mobile device (such as a smartphone). In this case, the user looks at the number generated on the device or software and dials during the phone call. These numbers are different with each access.

Verification Questions: Also known as Knowledge-Based Authentication (KBA), where the user must answer specific questions asked by an attendant. The attendant, in turn, performs the checks manually, according to the registration of that user.

Traditional methods have two fundamental negative elements: (i) weaknesses that result in lower security levels, and (ii) decreased usability of the user, which becomes difficult to use.

In the case of the security level, companies adopt the three forms of joint authentication (passwords, tokens and verification questions), precisely because they do not rely solely on one authentication method.

In the case of usability, the user has to memorize a lot of information (such as passwords, dates, names, last transactions), have to load devices (such as cards or devices like keychains tokens), and waste time having to dialing numbers (passwords, tokens) or answering verification questions.

The following are some of the security issues that exist with each of the above authentication methods.

[0031] Password: The attacker can guess, try different combinations until they gain access or obtain the user's password via social engineering, phising or pharming. Once discovered, the password can be used for fraud until it is overwritten by the user or locked out by the company. In addition, a password can be captured during communication, or when entered by the user on the device or the company's own system. Once discovered, the password can give access to the system or lead to the replay attack.

[0032] Token: It has major usability issues as the user has to carry a card or device to access the current valid number. Once the current valid number is obtained, the user must dial the number on the device. There is a possibility of attacks, but for the limited period of validity of that OTP. But attacks can be performed if the attacker obtains the seed that is used to calculate the OTP number. In the case of the security card, in addition to the limited number that facilitates replay attacks, there are attacks where users are tricked into entering all card numbers on fake websites.

[0033] Verification questions: Generally, questions are common and easy for fraudsters to find out, which makes their effectiveness low.

There are also methods in mobile telephone devices that authenticate access from the telephone call itself to a remote service using DTMF caller ID.

These technical means are known to provide more secure authentication, such as the generation of a one-time password (OTP). However, these are typically provided as standalone systems that are not closely integrated with the service to which the user is being authenticated.

[0036] The current state of the art anticipates some patent documents dealing with the subject matter regarding the use of OTP to validate the mobile device US 8296562 entitled "Out of Band System and Method for Authentication" - validates the user's mobile device. Validation is performed by sending an OTP token to the user's device via an OOB (Out-Of-Band) channel. Using this mechanism avoids Caller ID Spoofing attacks, in which the attacker pretends to be the legitimate user by manipulating the originating telephone number as if it were the victim's. The SMS message containing the OTP token is sent to the user's phone number. Software installed on the user's device identifies the SMS received from the service provider's SMS server and extracts the information from the OTP token. Then the SMS can be deleted and the same OTP token is sent over the data channel to the authentication server, which in turn validates this OTP token, thus completing the OOB authentication cycle by using two different channels. communication: data and mobile telephony (SMS).

In the proposed invention the OOB authentication method of the previous document is used only as a tool for device validation. Once this is done, the OTP seed that is used to generate the transparent token is sent. The proposed invention seeks, rather than validating the device, to achieve a much higher level of security and usability through the security method for transparent user authentication via public telephone using the DTMF signal.

Document KR20070081391A entitled “Acoustic One Time Password System for Tele Banking Only” uses the main focus approach on beeps generated by a specific device, which should be manipulated by the user as the device approaches the telephone microphone to the emission of sounds. In this case, the user must choose between buttons for creating a legitimate sound token or a fake token, to avoid phishing epharming.

In this proposed invention, unlike the previous document method that uses specific device, transparent authentication of users is done via public telephony using DTMF signal for sending numbers representing OTP, without the user having to perform any action or have to use a specialized device. Thus, there is better usability and greater security in the use of the transparent token, which is generated at each access from an OTP seed and a Device ID.

Document US2012066749A1 entitled “Method and Computer Program for Generation and Verification of OTP Between Server and Mobile Device Using Multiple Channels” - requires the user to authenticate via two distinct channels in each communication.

[0041] In the proposed invention, two channels are used only during the client application startup, installation and configuration step, in a transparent manner to the user who does not need to take any action. All subsequent uses require only a single channel, which allows for better usability and greater user safety.

[0042] Document GB2495474A entitled “Mobile Device User Authentication Within a Telephone Call, Messaging Session Or At A Physical Location” - the user must provide a password before using the OTP token, so it requires user action.

In this proposed invention there are a number of checks for changing safety parameters, such as the OTP seed, which are performed transparently as well as their use. The transparent token object of this method also performs a calculation between the OTP token generated from the OTP seed and the Mobile Device ID, which is sent via telephone channel to the authentication server via DTMF signals. In the proposed invention all user interactions with the authentication system are done transparently.

[0044] Document US2007083918A1 entitled "Validation of Call-out Services Transmitted Over a Public Switched Telephone Network" - encryption-based mechanisms are provided to protect the telephone network infrastructure, which in turn is used for traditional authentication methods, like passwords or OTP tokens, where users would continue to interact in a traditional way with the audible response unit (IVR). In this case, the message is transmitted using cryptographic methods and HTTP digest and has a long sequence of numbers, making it more difficult to use on telephone channels via DTMF.

[0045] In this proposed invention there is no need for user interaction, which need not type anything in their access, since the transparent token performs this function. In this invention, the sequence of numbers is from 4 to 8 digits facilitating their use on telephone channels.

OBJECTIVES OF THE INVENTION

It is the purpose of this security method for user authentication via public telephony using DTMF signal to improve user security and usability when accessing services via voice and public telephony channels.

The purpose of this security method for user authentication via public telephony is to propose a use where no direct interaction between the user and the device is required.

[0048] It is the purpose of this security method for user authentication via public telephony not to force the user to carry additional devices such as a token (keychain) or a security card.

It is the objective of this security method for telephony user authentication to provide a higher level of security when compared to a traditional OTP token.

GENERAL DESCRIPTION OF THE INVENTION

[0050] The security method for transparent authentication of users via public-tone public telephony has two sides, one side being the client deployed on a mobile cellular device, and the other side the server integrated with the audible response unit ( URA). Instead of dialing the service provider's telephone number, the user uses an application (software) installed on the user's mobile device for this purpose. This software dials the service provider's number by entering the number of the transparent token generated on the phone. The user no longer needs to know the service provider's number to dial, and the transparent token is automatically sent to the audible response unit (IVR) via public telephony, without the need for any action by the user and without the internet. . The transparent token is time-based and synchronized with the server. The Audible Response Unit (IVR) translates the DTMF signal for the token received by the client and compares it to the calculated server equivalent that is synchronized. If the numbers are the same, the IVR confirms the token and sends this information to the service provider. This method can be used in anti-fraud systems to assess the risk of such access, can eliminate verification questions by the Call Center attendant, or even authenticate user access by telephone call. Authentication of access is then done securely and without any action on the part of the user, and the company can validate that access using the transparent token. The transparent token can also be used in conjunction with other authentication methods appropriate for the voice channel, such as voice biometrics.

DESCRIPTION OF DRAWINGS

[0051] The present invention will be better understood from the following detailed description and the accompanying accompanying figures, in which: Figure 1: Block diagram showing the main components of the authentication system with the user accessing the service of the company by voice channel.

Figure 2: Block diagram showing key components of transparent authentication system calculated from OTP token and User Device ID.

Figure 3: Block diagram showing the main components of the authentication system using the transparent token.

Figure 4: Block diagram showing key components of the installation and initial configuration of the transparent token.

Figure 5: Block diagram with the main components of OTP seed sending using OOB (Out-Of-Band).

DETAILED DESCRIPTION OF THE INVENTION

The security method of user authentication via public telephony using the proposed DTMF signal has two sides, on one side being the client (implemented on a mobile device) and on the other side the server (integrated with the audible response unit). -URA). Instead of dialing the service provider's phone number, the user uses a software application installed on the mobile device. This software makes the telephone call to the service provider's number by entering the transparent token number generated on the mobile phone. The user no longer needs to know the service provider's number to dial, and the transparent token is automatically sent to the IVR via public telephony, without any action on the part of the user (Figure 1), without the need for the internet. The transparent token is time-based and synchronized with the server. The audible response unit (URA) translates the DTMF signal for the token received by the client and compares it to the calculated server equivalent that is synchronized. If the numbers are the same, the audible response unit confirms the token and sends this information, which can be used in anti-fraud systems, or can eliminate verification questions by the Call Center attendant, or even authenticate the telephone call. Figure 1 shows a block diagram where in (101) the user on his mobile device opens the service provider software, the software has a transparent token algorithm that performs a security calculation to generate a unique number from the OTP token (102) and mobile device-specific information synchronized with the server. This number is sent via DTMF signal (103) to the server at the time of dialing. The software is then responsible for the generation of the OTP number, security calculation using OTP token and mobile device specific information (Device ID), the incorporation of this transparent token number into the company's telephone number, and (104) the dial the company number along with the generated transparent token. The access is then made securely and without any action on the part of the user, and the company can validate that access using the transparent token. The transparent token can be seen in Figure 2.

The transparent token is generated according to (Figure 2), initially at (201) the mobile device ID is obtained then the OTP seed is obtained from its secure storage on the mobile device (202) , which in turn generates an OTP token (203) which then performs cryptographic operation (204) between the Device ID and the OTP token and thus hash the cryptographic algorithm of this operation (205). that the hash cryptographic algorithm obtained from the OTP token and the mobile device (Device ID) is the transparent token (206). The transparent token calculation is performed on the user's mobile device as well as on the authentication server.

The authentication flow using a transparent token is seen in (Figure 3) initially at (301) obtaining the mobile device ID (Device ID) where the OTP seed stored in device (302) below is obtained. The transparent token security calculation is performed (303) followed by the incorporation of the transparent token in the telephone call (304). Then a telephone call is made to service the service provider (305). service provider decodes the transparent token received via DTMF (306) and the audible response unit (IVR) sends the transparent token to the authentication server (307) the authentication server performs the security calculation of the transparent token (308), then the server compares the received values with the calculated values (309) and then the server validates that access (310).

Transparent token calculation is performed on both the user's mobile device and the authentication server. Software installation, that is, the application on the mobile device by the user causes several security parameters to be initially set. The main one is the OTP seed, which is used for the generation of the OTP token, which is unique and has a validity determined by time, that is, each generated OTP token has validity for a determined time. The OTP token, in turn, is used for transparent token calculation. All authentication is performed by checking the transparent token. In addition to the OTP seed, which is generated on the authentication server and must be sent to the software, the Device ID is sent to the server. The flow that shows the operations performed during the initial installation and configuration of the transparent token is seen in Figure 4.

The initial installation and configuration of the transparent token can be verified in the block diagram of (Figure 4), initially we get the Device ID (401) the server at the service provider receives the request for generating a transparent token (402) then the server receives from the user the mobile device ID (403) then the server generates the OTP seed (404) and then the server validates the user's device via channel OOB (Out-Of-Band) and sends the OTP seed (405). [0052] Still in the process of installing and initially configuring the transparent token, there is a need for the user to receive the OTP seed, which is used for OTP token generation, which in turn is used for transparent token calculation. This flow can be seen in (Figure 5).

Sending OTP seed using OOB (Out-Of-Band) can be seen in the block diagram of (Figure 5), where the authentication server receives the user's Mobile Device ID via the channel. (501) the authentication server generates the OTP seed (502), the authentication server generates the OTP token using the seed (503) and the authentication server sends the OTP token in an SMS (cell channel) message (504) ), and the user receives an OTP token SMS (505) and the software transparently opens the OTP token SMS sent by a registered number (service provider) (506), the user sends the token via the data channel OTP to the authentication server (507), and the authentication server compares the received OTP token with the one previously generated, thus validating the source telephone number (508) and after validating the telephone number and OTP token, the server authentication channel sends the OTP seed to the user via data channel (509).

Submission is performed using the Out-Of-Band (OOB) system and method that validates the user's mobile device prior to sending the OTP seed. Validation is performed by sending an OTP token to the user's device via an out-of-band (OOB) channel, such as SMS. Using this mechanism avoids Caller ID Spoofing attacks, where the attacker pretends to be the legitimate user by manipulating the phone number as if it were the victim's. The SMS message containing the OTP token is sent to the user's phone number. Software installed on the user's mobile device identifies the SMS received from the service provider's SMS server number and extracts the information from the OTP token. Then the SMS can be deleted and the same OTP token is sent over the data channel to the authentication server, which in turn validates this OTP token, thus completing the OOB (Out-Of-Band) authentication cycle.

In this way, the legitimate user's mobile device can be authenticated and is ready to receive the custom seed to generate OTP to make transactions on public telephony.

The security method for transparent authentication of users via public telephony using DTMF signal can also be implemented for other channels such as internet or mobile. If the transparent token is used on the mobile channel, access to a service can be initiated using the transparent token, which ensures greater security compared to traditional methods. In addition, the proposed method can be used in conjunction with known methods such as biometrics.

In the case of implementing the proposed method, the transparent token has been implemented so that a user's telephone call for access to a service as a call center is validated prior to the use of biometrics.

[0062] Using them together makes systems more secure, transparent to the user, without the user having to take additional actions or having to choose an additional password or having to carry an additional device. In implementing this proposed invention, the user performs telephone dialing and biometric authentication. If the phone call does not go through the transparent token check and the biometrics results lead to doubt, then traditional methods such as verification questions are needed. Thus, the use of the transparent token assists in user authentication, with the added benefit of saving attendance time by eliminating verification questions in this implementation of the invention. Additional fraud in telephone services such as SIM cloning or telephone number cloning can also be minimized by using the transparent token.

Claims (6)

1) “USER AUTHENTICATION SECURITY METHOD FOR DTMF SIGNAL PUBLIC TELEPHONY”, consisting of the user with a mobile cellular device, and a server integrated with the audible response unit (IVR) characterized by enabling the user to use an application on the Your mobile cellular device that automatically generates and sends a transparent token to a publicly-telephony-audible response unit using DTMF signal, time-based and synchronized with the server for secure authentication between parties. 2) “SECURITY METHOD FOR AUTHENTICATING USERS BY DTMF SIGNAL PUBLIC TELEPHONY” according to claim 1 characterized in that a transparent token is generated on the user's mobile device from a security calculation using OTP seed and user information. ID of your mobile device; the IVR translates the DTMF signal for the received transparent token and compares it to the calculated equivalent on the server that is synchronized 3) “SECURITY METHOD FOR AUTHENTICATING USERS BY DTMF SIGNAL PUBLIC TELEPHONY” according to claim 1 characterized in that an application installed on the user's mobile cellular device is responsible for generating a single number OTP seed; by calculating security using OTP token and mobile device specific information (Device ID); by incorporating this transparent token number into the company phone number, and by dialing the app to the company number along with the generated transparent token. 4) "SECURITY METHOD FOR USER AUTHENTICATION BY DTMF SIGNAL PUBLIC TELEPHONY" according to claim 1 characterized in that transparent token calculation is performed on the user's mobile device and server, and sent for validation and authentication on the server Authentication 5) “SECURITY METHOD FOR AUTHENTICATING USERS BY PUBLIC TELEPHONY USING DTMF SIGNAL” according to claims 1 and 4 characterized in that in the installation of the mobile application the OTP seed has a determined expiration time. 6) “SECURITY METHOD FOR AUTHENTICATING USERS THROUGH DTMF SIGNAL PUBLIC TELEPHONY” according to claim 5 and characterized by the process of installation and initial configuration of the transparent token there is a need for the user to securely receive the OTP seed, which is used for OTP token generation, which in turn is used for transparent token calculation.