Patent DE68242C successfully refreshed from Google Patents.
Patent US5625689A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5625689A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for secure data storage and manipulation using magnetic media

Assignee: Washington University in St. Louis
•
Filing: 1995-04-05
•
Granted: 1997-04-29
•
Expires: 2015-04-05
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Data recorded on a magnetic medium may be securely identified and manipulated for use in credit balance applications by determining a magnetic fingerprint benchmark on the medium as well as a distance between this benchmark and any pre-selected magnetic feature such as a magnetic transition of a data bit of the data set. Verification of the data may be achieved by measuring this distance and comparing it with the distance recorded at the time that the data was originally placed on the medium. As there is a detectable difference in accuracy between reading this distance as contrasted with illegitimate attempts to write false data at a pre-selected distance from the benchmark, attempts at forgery are detectable.

Inventors

  • 👤 Ronald S. Indeck
  • 👤 Marcel W. Muller

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 23:03
CPC Classifications
G; G06; G06K; G06K1/00; G06K1/12; G06K1/125; G06F; G06F21/00; G06F21/70; G06F21/78; G06F21/79; G06K19/00; G06K19/06; G06K19/06187; G06K19/08; G06K19/10; G06K19/12; G11; G11B; G11B20/00; G11B20/10; G11B20/10009; G11B20/18; G11B20/1816; G11B20/24; G11B5/00; G11B5/02; G11B5/027; G11B5/035; G11B5/48; G11B5/54; G11B5/58; G11B33/00; G11B33/10; G11B5/008; G11B5/00813; G11B5/488

Claims Analysis

Total Claims: 26
Claim 1
Independent Claim 54 words
A method for recording verifiable data on a magnetic medium, said method comprising the steps of: writing data onto a magnetic medium, determining a relative position of said data on said medium with respect to a benchmark on said magnetic medium, and storing said relative position for later use in verifying said stored data.
Claim 2
Independent Claim 54 words
A method for recording verifiable data on a magnetic medium, said method comprising the steps of: writing data onto a magnetic medium, determining a relative position of said data on said medium with respect to a benchmark on said magnetic medium, and storing said relative position for later use in verifying said stored data.
Claim 3
Dependent Claim 26 words
The method of claim 1 further comprising the step of: locating a benchmark on said magnetic medium by locating a magnetic fingerprint of said magnetic medium.
Claim 4
Dependent Claim 27 words
The method of claim 2 wherein said determining step includes the step of: measuring the distance between said benchmark and a magnetic feature of said recorded data.
Claim 5
Dependent Claim 21 words
The method of claim 3 wherein said storing step includes the step of recording said measured distance as said relative position.
Claim 6
Dependent Claim 21 words
The method of claim 1 wherein said storing step includes the step of storing said relative position on said magnetic medium.
Claim 7
Dependent Claim 21 words
The method of claim 4 wherein said storing step includes the step of storing said relative position on said magnetic medium.
Claim 8
Dependent Claim 24 words
The method of claim 6 wherein the step of measuring includes the step of measuring the distance between said benchmark and a pre-determined bit.
Claim 9
Dependent Claim 12 words
The method of claim 7 wherein said bit is a data bit.
Claim 10
Dependent Claim 37 words
The method of claim 7 further comprising the step of verifying said data including the steps of measuring the distance between said benchmark and said predetermined bit, and comparing said measured distance with said recorded measured distance.
Claim 11
Dependent Claim 37 words
A magnetic medium having verifiable data recorded thereon including a benchmark located on said magnetic medium, data recorded on said magnetic medium, and said data being recorded at a determined relative position with respect to said benchmark.
Claim 12
Dependent Claim 37 words
A magnetic medium having verifiable data recorded thereon including a benchmark located on said magnetic medium, data recorded on said magnetic medium, and said data being recorded at a determined relative position with respect to said benchmark.
Claim 13
Dependent Claim 20 words
The magnetic medium of claim 10 wherein said benchmark comprises a magnetic fingerprint at any position on said magnetic medium.
Claim 14
Dependent Claim 17 words
The magnetic medium of claim 11 wherein said determined relative position is recorded on said magnetic medium.
Claim 15
Dependent Claim 25 words
The magnetic medium of claim 11 wherein said determined relative position comprises the distance between said benchmark and a magnetic feature of said recorded data.
Claim 16
Dependent Claim 17 words
The magnetic medium of claim 13 wherein said determined relative position is recorded on said magnetic medium.
Claim 17
Independent Claim 43 words
A method for verifying data stored on a magnetic medium, said magnetic medium having a benchmark located thereon, said method comprising the steps of: measuring the distance between said data and said benchmark, and comparing said measured distance with a pre-recorded measured distance.
Claim 18
Independent Claim 43 words
A method for verifying data stored on a magnetic medium, said magnetic medium having a benchmark located thereon, said method comprising the steps of: measuring the distance between said data and said benchmark, and comparing said measured distance with a pre-recorded measured distance.
Claim 19
Dependent Claim 26 words
The method of claim 15 wherein said benchmark comprises a magnetic fingerprint and wherein the step of measuring includes the step of locating said magnetic fingerprint.
Claim 20
Dependent Claim 33 words
The method of claim 16 wherein the step of measuring includes the steps of locating a magnetic feature of said data and measuring the distance between said magnetic fingerprint and said magnetic feature.
Claim 21
Dependent Claim 18 words
The method of claim 17 further comprising the step of retrieving the magnetic fingerprint from a stored location.
Claim 22
Dependent Claim 45 words
The method of claim 18 wherein both of said magnetic fingerprint and said pre-recorded measured distance are stored on said magnetic medium, and further comprising the step of retrieving both of said magnetic fingerprint and said pre-recorded measured distance from storage on said magnetic medium.
Claim 23
Independent Claim 81 words
A method for securely controlling the manipulation of data stored on a magnetic medium, said method comprising the steps of: verifying the authenticity of data stored on said magnetic medium by comparing the distance between said data and a benchmark on said magnetic medium, with a stored value corresponding to said distance, manipulating said data if said comparison is satisfactory, storing said manipulated data on said magnetic medium, and storing a new measured distance between said manipulated data and said benchmark.
Claim 24
Independent Claim 81 words
A method for securely controlling the manipulation of data stored on a magnetic medium, said method comprising the steps of: verifying the authenticity of data stored on said magnetic medium by comparing the distance between said data and a benchmark on said magnetic medium, with a stored value corresponding to said distance, manipulating said data if said comparison is satisfactory, storing said manipulated data on said magnetic medium, and storing a new measured distance between said manipulated data and said benchmark.
Claim 25
Dependent Claim 26 words
The method of claim 20 wherein said benchmark comprises a magnetic fingerprint and wherein said step of comparing includes the step of locating said magnetic fingerprint.
Claim 26
Dependent Claim 35 words
The method of claim 21 wherein values corresponding to both of said magnetic fingerprint and said distance are stored on said magnetic medium and wherein the comparison step includes the step of retrieving said values.

References Cited (Backward Citations)

US4038596A Cited
US4806740A Cited
US4985614A Cited
US5365586A Cited
US5408505A Cited
US5428683A Cited
US5546462A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-04-28 2000-10-28 2001-04-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-04-28 2004-10-28 2005-04-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-04-28 2008-10-28 2009-04-29 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag