Adaptive system profile

Abstract

An approach to generating and regenerating a profile value from features of a system (e.g., a computer system), allows for certain changes of features of the system over time. The system may correspond to a client computer or a particular component of the client computer or a user of a client computer, and may also correspond to a combination of the user (i.e., a biometric characterization of the user) and the client computer or a component of the computer. The profile value may be used, for example, for purposes including identification, authentication, key generation, and other cryptographic functions involving the system.

What is claimed is: 
     
         1 . A method for repeatedly generating a profile value on a system, the method comprising:
 in a first phase,
 determining a plurality of features of the system, 
 grouping the determined features into a plurality of groups such that at least some features of the plurality of features is omitted from each group of one or more of the groups, 
 computing a function of the features in each of the groups to yield a plurality of corresponding group-specific values, and 
 encoding a profile value using the group-specific values to yield an encoding, and storing said encoding and removing the profile value from the system, 
 wherein the encoding is such that fewer that all the group-specific values are required to regenerate the profile value using the encoding; and 
   repeatedly in successive phases after the first phase,
 determining some or all of the plurality of features of the system, 
 grouping the determined features into at least some of the plurality of groups used in a prior phase of the first phase or the successive phases, and 
 recomputing the function of the features in each of the at least some of the groups to yield a plurality of corresponding recomputed group-specific values, and 
 decoding the profile value using the stored encoding and the recomputed group-specific values. 
   
     
     
         2 . The method of  claim 1  wherein the profile value comprises a pseudo-random value. 
     
     
         3 . The method of  claim 1  further comprising, in the first phase and in a successive phases, using the profile value to generate a cryptographic key. 
     
     
         4 . The method of  claim 3  further comprising, in a successive phase, using the cryptographic key for an interaction between the computing system and another computing system. 
     
     
         5 . The method of  claim 3  further comprising, in a successive phase, using the decoded profile value for at least one of authentication and secure communication between the computing system and another computing system. 
     
     
         6 . The method of  claim 1  wherein the features of the system comprise a feature selected from a group consisting of hardware features, software features, user features, and environment features. 
     
     
         7 . The method of  claim 1  wherein during at least some of the successive phases after the first phase, the method further includes:
 repeating encoding of the profile value using recomputed group-specific values to yield a recomputed encoding, and storing said recomputed encoding for use a subsequent phase. 
 
     
     
         8 . The method of  claim 1  wherein encoding the profile value using the group-specific values to yield the encoding includes separately encoding the profile value using each group-specific values to yield corresponding group-specific encodings. 
     
     
         9 . The method of  claim 8  wherein decoding the profile value using the stored encoding and the recomputed group-specific values includes using the group-specific encodings to generate a plurality of decodings of the profile value. 
     
     
         10 . The method of  claim 9  wherein decoding the profile value further includes determining the profile value according to a relative majority of the decodings of the profile value. 
     
     
         11 . The method of  claim 9  wherein decoding the profile value further includes determining the profile value according to a threshold number of the decodings of the profile value having a same value. 
     
     
         12 . The method of  claim 1  wherein the plurality of groups are specified using a random number. 
     
     
         13 . The method of  claim 12  wherein grouping the determined features in the initial phase and in the successive phases includes determining the random number. 
     
     
         14 . The method of  claim 1  wherein computing a function of the features in a group includes using a non-invertible mathematical function. 
     
     
         15 . The method of  claim 1  wherein the system belongs to a group consisting of a personal computing device and a device with an embedded processor. 
     
     
         16 . The method of  claim 1  wherein the system comprises a person, and the features comprise one or more biometric features of the person. 
     
     
         17 . The method of  claim 1  wherein the system comprises a computing system, and the features comprise one or more computing hardware features of the computing system. 
     
     
         18 . The method of  claim 1  wherein the system comprises a computing system, and the features comprise one or more software features of the computing system. 
     
     
         19 . Software comprising instructions stored on a non-transitory machine-readable medium that when executed by a processor to:
 in a first phase,
 determine a plurality of features of a system, 
 group the determined features into a plurality of groups such that at least some features of the plurality of features is omitted from each group of one or more of the groups, 
 compute a function of the features in each of the groups to yield a plurality of corresponding group-specific values, and 
 encode a profile value using the group-specific values to yield an encoding, and storing said encoding and removing the profile value from the system, 
 wherein the encoding is such that fewer that all the group-specific values are required to regenerate the profile value using the encoding; and 
   repeatedly in successive phases after the first phase,
 determine some or all of the plurality of features of the system, 
 group the determined features into at least some of the plurality of groups used in a prior phase of the first phase or the successive phases, and 
 recompute the function of the features in each of the at least some of the groups to yield a plurality of corresponding recomputed group-specific values, and 
 decode the profile value using the stored encoding and the recomputed group-specific values.