Document Hashing is a cryptographic process that converts an electronic document into a fixed-size hash value or hash code. This unique hash represents the document’s contents in a compact form. In eSignature workflows, hashing ensures that even a minor change in the document alters the hash value, making it easy to detect any tampering. It is a key element in maintaining data integrity during digital signing.
Why is Document Hashing Important in eSignatures?
- Ensures Integrity: Verifies that a document remains unaltered from the time it is signed, as any changes produce a different hash value.
- Enhances Security: Combined with digital signatures, hashing ensures that signatures are linked to the specific content of a document, preventing forgery.
- Speeds Verification: Cryptographic hash functions like SHA-256 generate quick hash values, making the verification process efficient even for large documents.
- Enables Legal Compliance: Required for compliance with regulations like eIDAS and ESIGN Act, which demand that digitally signed documents maintain integrity.
Key Features of Document Hashing in eSignature Platforms
- One-Way Hash Function: Hashing functions like SHA-256 produce unique hash values for each document, ensuring irreversibility.
- Digital Fingerprint: The hash serves as a digital fingerprint for the document, making it easy to detect any modifications.
- Fixed-Length Output: Hashing generates a fixed-length output regardless of the size of the input, simplifying the verification process.
- Integration with Digital Signatures: Works with public-private key encryption to ensure that the signed document is secure and tamper-evident.
Certinal eSign’s Document Hashing Features
- SHA-256 Encryption: Certinal uses SHA-256 for document hashing, offering high security and integrity for signed documents.
- Tamper Detection: Certinal’s platform checks the hash value at the time of verification, ensuring that any alterations to the document are immediately flagged.
- Seamless Integration: Certinal integrates document hashing into its signing process, ensuring that every digitally signed document remains secure from creation to storage.
- Hash Verification: Certinal provides users with easy access to verify document hashes, making audit processes simpler and more transparent.
How Document Hashing Works in Certinal eSign
- Upload the Document: The document is uploaded to Certinal, where a unique hash value is generated using SHA-256.
- Hashing During Signing: The hash value is encrypted with the signer’s private key, creating a digital signature.
- Verification: Upon retrieval, the system recalculates the hash value and compares it to the original. Any discrepancies indicate that the document has been altered.
- Secure Storage: The hash value is stored as part of Certinal’s audit trail, providing a tamper-evident
FAQs
- What is hashing in digital signature?
Hashing in digital signatures transforms a document’s content into a unique hash value. This ensures that even a small change to the document will produce a different hash, making tampering detectable.
- Which hashing function is used in the signature?
Most eSignature solutions, including Certinal, use SHA-256 for hashing due to its balance of security and efficiency in producing unique hash values.
- How to generate a digital signature using a hash code?
To generate a digital signature, a hash code of the document is created using a hash function like SHA-256. This hash is then encrypted with the signer’s private key, creating a secure digital signature.