Abstract:
An apparatus and method are disclosed for determining authentication frequency (i.e., the length of time between authenticating and re-authenticating a user) and challenge type (e.g., username/password, fingerprint recognition, voice recognition, etc.) based on what software applications a user is running on a data-processing system, and how those applications are being used (e.g., what functions are used, what data is input to or output by the application, how often and for how long applications are used, what input devices and output devices are used, etc.) Advantageously, the illustrative embodiment enables authentication frequency and challenge type to be adjusted based on the likelihood of malicious activity and/or the potential cost of malicious activity, as inferred from current and past application usage. In addition, the illustrative embodiment enables selection of an authentication challenge type that is less intrusive to a user based on current application usage.

Description:
CROSS-REFERENCE TO RELATES APPLICATIONS 
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 11/942,670, filed 19 Nov. 2007 (now pending), entitled “Determining Authentication Challenge Timing And Type” (Attorney Docket: 630-280us), which is incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to computer security in general, and, more particularly, to authentication. 
       BACKGROUND OF THE INVENTION 
       [0003]    In some instances it is desirable for security reasons to require that the user of a data-processing system (e.g., a wireless telecommunications terminal, a personal computer, a server, etc.) be authenticated before the user is permitted to access an application or resource of the data-processing system. Typically a user is presented with an authentication challenge, and the user must supply a valid response to the challenge. Examples of different types of authentication challenges include:
       requiring a user to furnish his or her username and password;   requiring a user to consult an electronic token device or a list of numbers in order to furnish a one-time password;   requiring a user to answer a pre-arranged secret question (e.g., “What is your mother&#39;s maiden name?”, “What was your first telephone number?”, etc.); and   biometrics (e.g., fingerprint recognition, voice recognition, retinal or iris scan, etc.).
 
Furthermore, in some instances the user of wireless telecommunications terminal  110  might be periodically challenged (i.e., the user is periodically re-authenticated) for greater security.
       
 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention enables authentication frequency (i.e., the length of time between authenticating and re-authenticating a user) and challenge type (e.g., username/password, fingerprint recognition, voice recognition, etc.) to be determined based on what software applications a user is running on a data-processing system (e.g., a payroll application, a browser-based banking application, an email client, etc.), and how those applications are being used (e.g., what functions are used, what data is input to or output by the application, how often and for how long applications are used, what input devices are used, what output devices are used, the speed and manner in which data is input to an application, etc.) In accordance with the illustrative embodiment, both current and historical application usage can be considered in these determinations. 
         [0009]    The present invention is advantageous in that it enables authentication frequency to be increased (i.e., less time between re-authentication challenges, which corresponds to tighter security) and the challenge type to be stronger (i.e., more secure) in situations where it is more likely that a malicious user has gained access to a data-processing system, or where a false person having access can be dangerous to the real user. For example, such situations might include:
       when there is a large withdrawal from a banking application;   when a particular operation in a human-resources application is invoked repeatedly for several different employees;   when application usage is substantially different than the norm for a particular data-processing system at a particular day and time (say, a weekday morning); or   when the semantic content of a message sent via an email client application is unusual, or might be damaging to the real user or his or her employer.       
 
         [0014]    The present invention also advantageously enables the selection of an authentication challenge type that is less intrusive to a user based on current application usage. For example, a voice recognition challenge might be issued when a user is typing away at the keyboard in a spreadsheet application, while a typed username/password challenge might be issued when a user is playing a voice-controlled videogame. 
         [0015]    The illustrative embodiment comprises: presenting a first authentication challenge at a data-processing system at time t 1 ; and presenting a second authentication challenge at a data-processing system at time t 2 ; wherein the magnitude of t 2 -t 1  is based on usage of one or more applications of said data-processing system at one or more instants in time interval [t 1 , t 2 ]. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  depicts the salient elements of data-processing system  100 , in accordance with the illustrative embodiment of the present invention. 
           [0017]      FIG. 2  depicts a flowchart of a method for determining re-authentication challenge frequency and type, in accordance with the illustrative embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION  
       [0018]    For the purposes of the specification and claims, the term “calendrical time” is defined as indicative of one or more of the following: 
         [0019]    (i) a time (e.g., 16:23:58, etc.), 
         [0020]    (ii) one or more temporal designations (e.g., Tuesday, November, etc.), 
         [0021]    (iii) one or more events (e.g., Thanksgiving, John&#39;s birthday, etc.), and 
         [0022]    (iv) a time span (e.g., 8:00 PM to 9:00 PM, etc.). 
         [0023]      FIG. 1  depicts the salient elements of data-processing system  100 , in accordance with the illustrative embodiment of the present invention. As shown in  FIG. 1 , data-processing system  100  comprises transceiver  110 , memory  120 , clock  130 , input devices  140 - 1  through  140 -N, where N is a positive integer, output devices  150 - 1  through  150 -M, where M is a positive integer, and processor  160 , interconnected as shown. 
         [0024]    Transceiver  110  is capable of receiving external signals (e.g., via a wired network, via a wireless network, etc.) and forwarding information encoded in these signals to processor  160 , and of receiving information from processor  160  and transmitting signals that encode this information (e.g., via a wired network, via a wireless network, etc.), in well-known fashion. 
         [0025]    Memory  120  is capable of storing data, program source code, and executable instructions, as is well-known in the art, and might be any combination of random-access memory (RAM), flash memory, disk drive, etc. In accordance with the illustrative embodiment, memory  120  is capable of storing one or more applications (e.g., a payroll application, a video game, an email client, etc.), and of storing information regarding the use of these applications, such as how often an application is used, the time of last use, what functions in an application are used, how often functions are used, and so forth. 
         [0026]    Clock  130  is capable of transmitting the current time, date, and day of the week to processor  160 , in well-known fashion. 
         [0027]    Input devices  140 - 1  through  140 -N are capable of receiving input from a user and of forwarding the input to processor  160 , in well-known fashion. Examples of input devices  140 - 1  through  140 -N might include a numeric keypad, an alphanumeric keyboard, a fingerprint sensor, a microphone, a magnetic card reader, and so forth. 
         [0028]    Output devices  150 - 1  through  150 -M are capable of receiving information, including authentication challenges, from processor  160 , and of outputting the information to a user, in well-known fashion. Examples of output devices  150 - 1  through  150 -M might include a video display, a speaker, a vibration mechanism, and so forth. 
         [0029]    Processor  160  is a general-purpose processor that is capable of reading data from and writing data into memory  120 , of executing applications stored in memory  120 , and of executing the tasks described below and with respect to  FIG. 2 . As will be appreciated by those skilled in the art, in some embodiments of the present invention processor  160  might be a special-purpose processor, rather than a general-purpose processor. 
         [0030]      FIG. 2  depicts a flowchart of a method for determining re-authentication challenge frequency and type, in accordance with the illustrative embodiment of the present invention. In accordance with the illustrative embodiment, the tasks of  FIG. 2  are performed by data-processing system  100 . As will be appreciated by those skilled in the art, however, in some other embodiments of the present invention, one or more tasks of  FIG. 2 , such as the determination of the challenge frequency and type at task  240 , might instead be performed by another entity (e.g., an authentication server, etc.) and the result transmitted to transceiver  110  of data-processing system  100 . 
         [0031]    At task  210 , data-processing system  100  determines which of its applications are being used, and which functions of the applications are being used, in well-known fashion. 
         [0032]    At task  220 , the input capabilities of data-processing system  100  are determined. As will be appreciated by those skilled in the art, in embodiments of the present invention in which task  220  is performed by data-processing system  100  itself, data-processing system  100  merely has to check which of input devices  140 - 1  through  140 -N are currently enabled and functional; while in some other embodiments of the present invention, an authentication server or some other entity might transmit a message to data-processing system  100  that explicitly asks for its input capabilities; while in yet some other embodiments, an authentication server or some other entity might transmit a message to data-processing system  100  that asks for its manufacturer and model (e.g., Apple iPhone®, etc.), and then consult a database to determine the input capabilities of data-processing system  100  (under the assumption that all of data-processing system  100 &#39;s capabilities are currently enabled and functional). 
         [0033]    At task  230 , an authentication challenge type T and time Δ between challenges are determined based on:
       which applications of data-processing system  100  are currently being used, and for how long   which applications of data-processing system  100  have been used since the last authentication challenge at data-processing system  100 , as well as how often and for how long   historical usage of these applications, both in general and with respect to the current calendrical time   which application functions are currently being used,   which application functions have been used since the last authentication challenge at data-processing system  100 , and how often they have been used   historical usage of application functions, both in general and with respect to the current calendrical time   inputs to applications (e.g., the values of data, the number of inputs, the semantic content of text or spoken inputs, etc.),   outputs from applications (e.g., the values of data, the number of outputs, the type of outputs [e.g., audio, text, etc.], the semantic content of an output, etc.),   how input is supplied to applications (e.g., which input devices are used, the speed and manner in which input is supplied, such as how fast a user types or how often the backspace is used to make corrections, etc.), and   the input capabilities of data-processing system  100 .       
 
         [0044]    As will be appreciated by those skilled in the art, by considering what application functions are used and what inputs are supplied to the functions, the illustrative embodiment is capable of considering the potential cost or harm to the real user, or to his or her organization, in the determinations of task  230 . For example, a large cash withdrawal or a drastic reduction in the price of an item for sale could be very costly to the real user, while a defaced web page or a denial of service attack could result in unfavorable press for the real user&#39;s employer. 
         [0045]    As will further be appreciated by those skilled in the art, in some embodiments of the present invention, an authentication challenge type might comprise a plurality of successive challenges, rather than a single challenge, thereby enabling even “stronger” authentication challenges. For example, a challenge type determined at task  230  might be “fingerprint recognition, followed by iris scan.” 
         [0046]    As will further be appreciated by those skilled in the art, for embodiments of the present invention in which task  230  is performed by data-processing system  100 , the current day and time might be obtained from clock  130 , or might be obtained from an external source via transceiver  110 . Moreover, although in the illustrative embodiment historical application usage information is stored in memory  120 , in some other embodiments of the present invention this information might be stored in an external database and accessed by data-processing system  100  via transceiver  110 . As will further be appreciated by those skilled in the art, in some embodiments of the present invention, the collection, storing, and organization of this historical information might be performed by data-processing system  100  itself, while in some other embodiments of the present invention, another entity (e.g., an authentication server, etc.) might perform these functions. 
         [0047]    At task  240 , an authentication challenge of type T is generated, in well-known fashion. 
         [0048]    At task  250 , the authentication challenge generated at task  240  is presented to the user of data-processing system  100  at a time in accordance with Δ, in well-known fashion. After task  250 , the method of  FIG. 2  terminates. 
         [0049]    It is to be understood that the disclosure teaches just one example of the illustrative embodiment and that many variations of the invention can easily be devised by those skilled in the art after reading this disclosure and that the scope of the present invention is to be determined by the following claims.