Patent US5745573A successfully refreshed from Google Patents.
US5745573A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System and method for controlling access to a user secret
Assignee: McAfee LLC
•
Filing: 1997-01-10
•
Granted: 1998-04-28
•
Expires: 2017-01-10
Abstract
Abstract A system and method for data escrow cryptography are described. An encrypting user encrypts a message using a secret storage key (KS) and attaches a data recovery field (DRF), including an access rule index (ARI) and KS, to the encrypted message. The DRF and the encrypted message are stored in a storage device. To recover KS, a decrypting user extracts and sends the DRF to a data recovery center (DRC) that issues a challenge based on access rules (ARs) originally defined by the encrypting user. If the decrypting user meets the challenge, the DRC sends KS in a message to the decrypting user. Generally, KS need not be an encryption key but could represent any piece of confidential information that can fit inside the DRF. In all cases, the DRC limits access to decrypting users who can meet the challenge defined in either the ARs defined by the encrypting user or the ARs defined for override access.
Inventors
- 👤 Steven B. Lipner
- 👤 David M. Balenson
- 👤 Carl M. Ellison
- 👤 Stephen T. Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:10
CPC Classifications
H; H04; H04L; H04L9/00; H04L9/32; H04L9/3271; H04L9/08; H04L9/0894
Claims Analysis
Total Claims: 41
Claim 1
Independent Claim
135 words
A data recovery center, comprising: means for receiving an access rule from an access rule defining system in communication with the data recovery center, wherein said access rule includes an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; means for generating an access rule index and associating said access rule index with said access rule, wherein an access rule index is included within a data recovery field and allows the data recovery center to locate an access rule that control access, by an emergency decryptor, to a secret within a data recovery field; and means for communicating said access rule index to said access rule defining system.
Claim 2
Dependent Claim
135 words
A data recovery center, comprising: means for receiving an access rule from an access rule defining system in communication with the data recovery center, wherein said access rule includes an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; means for generating an access rule index and associating said access rule index with said access rule, wherein an access rule index is included within a data recovery field and allows the data recovery center to locate an access rule that control access, by an emergency decryptor, to a secret within a data recovery field; and means for communicating said access rule index to said access rule defining system.
Claim 3
Dependent Claim
168 words
The data recovery center of claim 1, further comprising access rule re-definition means for enabling said access rule defining system to re-define an existing access rule, said access rule re-definition means comprising: means for receiving from said access rule defining system a request to re-define said existing access rule, said request comprising a previously created access rule index associated with said existing access rule and a new access rule; means for retrieving from a storage device coupled to said data recovery center said existing access rule using said previously created access rule index as an index into said storage device; means for interacting with said access rule defining system in accordance with said existing access rule definition retrieved from said storage device to determine whether said access rule defining system is authorized to re-define said existing access rule; and means for replacing said existing access rule with said new access rule if said access rule defining system is determined to be authorized to re-define said existing access rule.
Claim 4
Dependent Claim
20 words
The data recovery center of claim 1, wherein said access rule is an authentication test that verifies a person's identity.
Claim 5
Dependent Claim
59 words
The data recovery center of claim 1, wherein said access rule comprises N prompt/reply pairs and is satisfied when said access rule defining system the numbers A and K (K≦A≦N) such that said access rule definition is satisfied if a user provides correct responses to K of the A prompt/reply pairs (K≦A≦N) that said data recovery center randomly selects.
Claim 6
Dependent Claim
46 words
The data recovery center of claim 1, wherein said access rule is a compound authorization rule of the form, k≦n, such that said access rule definition is satisfied if k of the n access rules identified by k of the n access rule indexes are satisfied.
Claim 7
Dependent Claim
23 words
The data recovery center of claim 1, wherein said access rule index is an address at which said access rule definition is stored.
Claim 8
Dependent Claim
14 words
The data recovery center of claim 1, wherein said secret is an encryption key.
Claim 9
Independent Claim
138 words
A method in a data recovery center, comprising the steps of: (1) receiving an access rule from an access rule defining system in communication with the data recovery center, wherein said access rule includes an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; (2) generating an access rule index and associating said access rule index with said access rule, wherein an access rule index is included within a data recovery field and allows the data recovery center to locate an access rule that control access, by an emergency decryptor, to a secret within a data recovery field; and (3) communicating said access rule index to said access rule defining system.
Claim 10
Independent Claim
138 words
A method in a data recovery center, comprising the steps of: (1) receiving an access rule from an access rule defining system in communication with the data recovery center, wherein said access rule includes an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; (2) generating an access rule index and associating said access rule index with said access rule, wherein an access rule index is included within a data recovery field and allows the data recovery center to locate an access rule that control access, by an emergency decryptor, to a secret within a data recovery field; and (3) communicating said access rule index to said access rule defining system.
Claim 11
Dependent Claim
160 words
The method of claim 8, further comprising the step of: (4) enabling a access rule defining system to re-define an existing access rule; step (4) comprising the steps of: (a) receiving from said access rule defining system a request to re-define said existing access rule, said request comprising a previously created access rule index associated with said existing access rule and a new access rule; (b) retrieving from a storage device coupled to said data recovery center said existing access rule using said previously created access rule index as an index into said storage device; (c) interacting with said access rule defining system in accordance with said existing access rule retrieved from said storage device to determine whether said access rule defining system is authorized to re-define said existing access rule; and (d) replacing said existing access rule with said new access rule if said access rule defining system is determined to be authorized to re-define said existing access rule.
Claim 12
Dependent Claim
43 words
The method of claim 8, wherein said step (1) comprises the step of receiving an access rule from an access rule defining system in communication with the data recovery center, wherein said access rule is an authentication test that verifies a person's identity.
Claim 13
Dependent Claim
65 words
The method of claim 8, wherein said step (1) comprises the step of receiving an access rule from an access rule defining system in communication with the data recovery center, wherein said access rule comprises N prompt/reply pairs and is satisfied when said access rule defining system provides correct responses to K of the A prompt/reply pairs (K≦A≦N) that said data recovery center randomly selects.
Claim 14
Dependent Claim
64 words
The method of claim 8, wherein said step (1) comprises the step of receiving an access rule from an access rule defining system in communication with the data recovery center, wherein said access rule is of the form, k≦n, such that said access rule is satisfied if k of the n access rules identified by k of the n access rule indexes are satisfied.
Claim 15
Dependent Claim
41 words
The method of claim 8, wherein said step (2) comprises the step of generating an access rule index and associating said access rule index with said access rule, wherein said access rule index is an address that references an access rule.
Claim 16
Dependent Claim
150 words
In an environment comprising a data recovery center and a access rule defining system, a method in said access rule defining system comprising the steps of: (1) generating an access rule, said access rule including an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; (2) registering said access rule with said data recovery center; (3) receiving from said data recovery center registration information resulting from registering said access rule with said data recovery center; and (4) storing said registration information in an access rule index file, wherein registration information is included within a data recovery field and allows said data recovery center to locate an access rule that controls access, by an emergency decryptor, to a secret within the data recovery field.
Claim 17
Dependent Claim
150 words
In an environment comprising a data recovery center and a access rule defining system, a method in said access rule defining system comprising the steps of: (1) generating an access rule, said access rule including an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; (2) registering said access rule with said data recovery center; (3) receiving from said data recovery center registration information resulting from registering said access rule with said data recovery center; and (4) storing said registration information in an access rule index file, wherein registration information is included within a data recovery field and allows said data recovery center to locate an access rule that controls access, by an emergency decryptor, to a secret within the data recovery field.
Claim 18
Dependent Claim
22 words
The method of claim 14, wherein said step (1) comprises the step of generating an authentication test that verifies a person's identity.
Claim 19
Dependent Claim
57 words
The method of claim 14, wherein said step (1) comprises the step of generating an access rule that comprises N prompt/reply pairs, wherein said access rule comprises N prompt/reply pairs and is satisfied when said access rule defining system provides correct responses to K of the A prompt/reply pairs (K≦A≦N) that said data recovery center randomly selects.
Claim 20
Dependent Claim
46 words
The method of claim 14, wherein said step (1) comprises the step of generating an access rule of the form, k≦n, such that said access rule is satisfied if k of the n access rules identified by k of the n access rule indexes are satisfied.
Claim 21
Dependent Claim
44 words
The method of claim 14, wherein said step (3) comprises the step of receiving from said data recovery center registration information resulting from registering said access rule with said data recovery center, wherein said registration information is an address that references an access rule.
Claim 22
Dependent Claim
158 words
A controller for enabling a processor to control access to user secret data, comprising: means for enabling said processor to generate an access rule, said access rule including an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; means for enabling said processor to register said access rule with a data recovery center; means for enabling said processor to receive from said data recovery center registration information resulting from registering said access rule with said data recovery center; and means for enabling said processor to store said registration information in an access rule index file, wherein registration information is included within a data recovery field and allows said data recovery center to locate an access rule that control access, by an emergency decryptor, to a secret within the data recovery field.
Claim 23
Dependent Claim
158 words
A controller for enabling a processor to control access to user secret data, comprising: means for enabling said processor to generate an access rule, said access rule including an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; means for enabling said processor to register said access rule with a data recovery center; means for enabling said processor to receive from said data recovery center registration information resulting from registering said access rule with said data recovery center; and means for enabling said processor to store said registration information in an access rule index file, wherein registration information is included within a data recovery field and allows said data recovery center to locate an access rule that control access, by an emergency decryptor, to a secret within the data recovery field.
Claim 24
Dependent Claim
18 words
The controller of claim 19, wherein said access rule is an authentication test that verifies a person's identity.
Claim 25
Dependent Claim
57 words
The controller of claim 19, wherein said access rule comprises N prompt/reply pairs and is satisfied when said access rule defining system numbers A and K (K≦A≦N) such that said access rule definition is satisfied if a user correctly provides correct responses to K of the A prompt/reply pairs (K≦A≦N) that said data recovery center randomly selects.
Claim 26
Dependent Claim
44 words
The controller of claim 19, wherein said access rule is a compound authorization rule of the form, k≦n, such that said access rule definition is satisfied if k of the n access rules identified by k of the n access rule indexes are satisfied.
Claim 27
Dependent Claim
21 words
The controller of claim 19, wherein said access rule index is an address at which said access rule definition is stored.
Claim 28
Dependent Claim
12 words
The controller of claim 19, wherein said secret is an encryption key.
Claim 29
Dependent Claim
161 words
A controller for enabling a processor to register a access rule defining system for data access control operations, comprising: means for enabling said processor to receive an access rule from an access rule defining system in communication with the data recovery center, wherein said access rule includes an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; means for enabling said processor to generate an access rule index and associating said access rule index with said access rule, wherein an access rule index is included within a data recovery field and allows the data recovery center to locate an access rule that control access, by an emergency decryptor, to a secret within a data recovery field; and means for enabling said processor to communicate said access rule index to said access rule defining system.
Claim 30
Dependent Claim
161 words
A controller for enabling a processor to register a access rule defining system for data access control operations, comprising: means for enabling said processor to receive an access rule from an access rule defining system in communication with the data recovery center, wherein said access rule includes an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; means for enabling said processor to generate an access rule index and associating said access rule index with said access rule, wherein an access rule index is included within a data recovery field and allows the data recovery center to locate an access rule that control access, by an emergency decryptor, to a secret within a data recovery field; and means for enabling said processor to communicate said access rule index to said access rule defining system.
Claim 31
Dependent Claim
18 words
The controller of claim 25, wherein said access rule is an authentication test that verifies a person's identity.
Claim 32
Dependent Claim
57 words
The controller of claim 25, wherein said access rule comprises N prompt/reply pairs and is satisfied when said access rule defining system numbers A and K (K≦A≦N) such that said access rule definition is satisfied if a user correctly provides correct responses to K of the A prompt/reply pairs (K≦A≦N) that said data recovery center randomly selects.
Claim 33
Dependent Claim
44 words
The controller of claim 25, wherein said access rule is a compound authorization rule of the form, k≦n, such that said access rule definition is satisfied if k of the n access rules identified by k of the n access rule indexes are satisfied.
Claim 34
Dependent Claim
21 words
The controller of claim 25, wherein said access rule index is an address at which said access rule definition is stored.
Claim 35
Dependent Claim
12 words
The controller of claim 25, wherein said secret is an encryption key.
Claim 36
Dependent Claim
134 words
An access rule defining system comprising: means for generating an access rule, said access rule including an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; means for registering said access rule with said data recovery center; means for receiving from said data recovery center registration information resulting from registering said access rule with said data recovery center; and means for storing said registration information in an access rule index file, wherein registration information is included within a data recovery field and allows said data recovery center to locate an access rule that controls access, by an emergency decryptor, to a secret within the data recovery field.
Claim 37
Dependent Claim
134 words
An access rule defining system comprising: means for generating an access rule, said access rule including an authentication test or a compound authorization rule, said access rule defining at least a portion of a procedure for authenticating an identity of an emergency decryptor, wherein emergency decryption comprises decryption using a data recovery field; means for registering said access rule with said data recovery center; means for receiving from said data recovery center registration information resulting from registering said access rule with said data recovery center; and means for storing said registration information in an access rule index file, wherein registration information is included within a data recovery field and allows said data recovery center to locate an access rule that controls access, by an emergency decryptor, to a secret within the data recovery field.
Claim 38
Dependent Claim
21 words
The access rule defining system of claim 31, wherein said access rule is an authentication test that verifies a person's identity.
Claim 39
Dependent Claim
43 words
The access rule defining system of claim 31, wherein said access rule comprises N prompt/reply pairs and is satisfied when said access rule defining system provides correct responses to K of the A prompt/reply pairs (K≦A≦N) that said data recovery center randomly selects.
Claim 40
Dependent Claim
42 words
The access rule defining system of claim 31, wherein said access rule is of the form, k≦n, such that said access rule is satisfied if k of the n access rules identified by k of the n access rule indexes are satisfied.
Claim 41
Dependent Claim
20 words
The access rule defining system of claim 31, wherein said registration information is an address that references an access rule.
References Cited (Backward Citations)
US4200770A
Cited
US4405829A
Cited
US4386233A
Cited
US4607137A
Cited
US4590470A
Cited
US4926480A
Cited
US4947430A
Cited
US4868877A
Cited
US5005200A
Cited
US5214702A
Cited
US5313637A
Cited
US5191611A
Cited
US4996711A
Cited
US5386470A
Cited
US5265163A
Cited
US5276736A
Cited
US5263157A
Cited
US5144665A
Cited
US5226080A
Cited
US5224163A
Cited
WO1992009161A1
Cited
EP0493232A1
Cited
US5267313A
Cited
US5200999A
Cited
US5265164A
Cited
US5276901A
Cited
US5210795A
Cited
US5347578A
Cited
US5280527A
Cited
US5276737B1
Cited
US5315658A
Cited
WO1993021708A1
Cited
US5276737A
Cited
US5315658B1
Cited
US5341426A
Cited
US5351293A
Cited
US5406628A
Cited
US5299263A
Cited
US5436972A
Cited
US5371794A
Cited
US5481613A
Cited
US5557346A
Cited
US5557765A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-04-27 | 2001-10-27 | 2002-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-04-27 | 2005-10-27 | 2006-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-04-27 | 2009-10-27 | 2010-04-28 | $7700.00 | Window Closed / Lapsed |