Nested Digital Signatures in Fixed Fields
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current digital signature schemes face challenges in embedding and validating multiple nested digital signatures without altering the file size of digitally produced documents, leading to corruption of previous signatures and difficulties in maintaining a verifiable chain of custody.
Innovation Solution
The implementation of a system and method that uses fixed fields in digital documents to embed multiple nested digital signatures, employing cryptographic techniques like hash algorithms to ensure signatures remain affixed and uncorrupted, allowing for independent verification and preservation of the chain of review.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If digital signatures are embedded within the digitally produced document itself, then the digital signature cannot be stripped off (forensically stronger), but the content of the digitally produced document is effectively changed and the size of the digitally produced document is necessarily changed
Solution Approach 1:
The patent embeds multiple digital signatures within fixed fields of a single digital document, nesting signatures sequentially without altering the overall document structure or file size. Each signature is placed in a predetermined fixed field, allowing multiple signatures to coexist nested within the document's metadata structure.
Solution Approach 2:
The patent pre-allocates fixed fields within the digital document structure before signatures are applied. These fixed fields are prepared in advance to accommodate digital signatures, ensuring that when signatures are embedded, they do not alter the document's file size or corrupt existing content.
2Reliability
If a second digital signature is added in sequence after the first digital signature, then a chain of custody is established, but the first digital signature is generally corrupted thereby rendering difficult precise reconstruction of the chain of custody
Solution Approach 1:
The patent divides the digital document into fixed fields, with specific fields designated for digital signatures. By segmenting the document structure and allocating dedicated fixed fields for each signature, the patent allows multiple signatures to be added sequentially without interfering with or corrupting previously embedded signatures, thereby preserving the integrity of the entire chain of custody.
3Adaptability or versatility
If digital signatures are wrapped in a digitally signed envelope, then multiple layers of wrapping corresponding to multiple individual digital signatures can be applied, but the wrapped file is no longer readily identifiable as the original file and the digital signature is effectively detached from the digitally produced and signed document
Solution Approach 1:
The patent merges multiple digital signatures directly into the digital document by embedding them in fixed fields within the document's own structure. This combining approach eliminates the need for separate envelope wrappers, allowing the document to maintain its original format and identity while incorporating multiple signatures internally, thus preserving both file identification and signature association.
Data Source
AI summary
A system and method are provided for implementing a digital signature scheme for embedding and validating multiple nested digital signatures in digitally produced documents without modifying a file size of the digitally produced and signed documents or otherwise corrupting previously-embedded digital signatures. A number of fixed fields are included in a digitally produced document, upfront, that will be populated with multiple digital signatures. With the fixed fields in the digitally produced documents, the entire file is cryptographically “hashed” and the individual digital signatures are independently verifiable via simple cryptographic schemes. Multiple digital signatures are embedded in documents including complex file formats in a manner that does not corrupt the documents. Known cryptographic techniques such as, for example, a known hash algorithm, are applied to the digitally produced documents including the multiple sequentially input digital signatures in a process that is independently verifiable.