Secure digital signatures

Introduction to digital signing technology

In today's digital world, the need for additional layers of security has become more important to protect businesses and the end consumer.

As the digital services world evolves, the ability to complete or sign documents digitally has become more important. There are a number of business considerations to align with important levels of electronic signing all surrounding the usual ‘who’, ‘what’ and ‘why’

  •        Is the ‘signing entity’ who they say they are?  - a ‘trusted identity’
  •        Can the signature and associated identity be validated?
  •        Does the signing model provide legal assurance?

Digital signing technology acts as an assurance that the document issuer is authentic and the document has not been tampered with. 

The security

When a document is submitted for digital signature, a hash algorithm of the PDF is sent to the digital signing authority. The value is based on the full content of the PDF document, and is then digitally signed by encrypting the hash value with the signer’s private key, and returned to be included in the generated PDF.

When the PDF is viewed in Adobe, the document hash is decrypted using a public key. If the decrypted values match Adobe has verification that the document has been signed by the verified signing authority and not modified and displays the blue digital signature banner.

An example of a document that has been digitally signed is shown below. This displays a blue band at the top, which indicates that the certificate is authentic and has not been tampered with. Additional details including the date/time of digital signature and the signing authority can also be accessed (see panel on left) by anyone opening the document in an up to date Adobe product.

Benefits to users

There are many benefits of using digital identity technology including: 

  • Added security, with unique identifying information, permanently embedded within a document e.g. PDF 
  • Each signature includes a date stamp to verify the time of signing
  • Global acceptance of digital signatures on legally binding documents because they understand that the security protocols that meet international standards in the field
  • Withstand stringent independent verification which cannot be altered by unauthorised parties
  • Saves time as documents can be signed immediately and produced when requested
  • Costs can be reduced as there is no need to print and post certificates

A number of our clients are currently using our digital signing service including the Isle of Man Ship Registry who apply digital signatures to ship certificates issued by the Registry. The certificates are produced in PDF format by the system, and are then sent to GlobalSign for signing, in real-time. Signed PDFs can then be dispatched to recipients all over the globe, safe in the knowledge that if they are intercepted and tampered with on-route, this will be immediately apparent to the true recipient – helped significantly by the ubiquity of the PDF format and the Adobe Acrobat Reader software. Furthermore, digitally signed certificates prove unequivocally that they were issued by the Isle of Man Ship Registry, at the date/time stamped into the document.

Learn more

Learn more about digital signing by contacting Bruce McGregor