What exactly does the PAdES format mean? Increasingly, digital documents are electronically signed. And, once recorded, they must be stored correctly – sometimes for several years, sometimes permanently.
In this context, the different extensions of the PAdES format allow different types of temporary validity to be established. In this article we will see specifically what this format and its different extensions consist of, its difference with other options and its use through Viafirma Documents.
What is the PAdES format?
PAdES is the acronym for PDF Advanced Electronic Signatures. It is a technical standard to refer to a set of extensions and restrictions that are used when electronically signing PDF documents.
This standard specifies precise profiles that make it compatible with ETSI standards for digital signatures.
By default, the electronic signature is always embedded within the signed PDF document, which can only be read by individuals. The PAdES system does not support parallel signing (the same document signed by several recipients without following a sequential order) and requires PDF software such as Adobe to sign and verify the electronic signature.
Types of extensions
Within this signature format, different profiles defined by PAdES (ETSI TS 102 778) have been developed, responding to different needs and scenarios:
- PAdES Basic. Basic profile that meets the requirements specified in ISO 32000-1.
- PAdES-BES Profile (Enhaced). Specifies an advanced PDF signature based on CAdES-BES and incorporates the option to include a time stamp (CADES-T) in the signature.
- EPES Profile (Enhaced). This profile specifies an advanced PDF signature based on CAdES-EPES. It adds to the previous level a signature policy identifier and, optionally, a reference to the type of commitment made.
- PAdES-LTV Profile (Long Term). Long-lived signature format. This profile allows the validity of PDF signatures to be extended indefinitely. It can be used in conjunction with the PAdES-CMS, PAdES-BES or PADES-EPES profiles. This profile is used to guarantee validation many years after the signature has been made. In other words, it guarantees long-term validity.
Differences with other formats
The choice between the two will depend on the type of document and what you want to do with them once they are electronically signed.
We show you other formats compatible with our solutions:
- CAdES (CMS Advanced Electronic Signatures): It is a set of signed data extensions with cryptographic message syntax (CMS), making it suitable for advanced electronic signature. Its main advantage is that electronically signed documents can also remain valid for long periods; even if the underlying cryptographic algorithms are broken.
- XAdES (XML Advanced Electronic Signatures): It is a set of extensions that are added to the XML-DSig recommendations, it is an XML file. It is suitable for signing financial transactions electronically. Its XML data structure is human readable and contains all the information necessary to identify the signatory.
If you are still not sure which electronic signature format to choose to optimise your processes, tell us about your use case and we will contact you as soon as possible.
Viafirma Documents: A complete, simple and secure solution that supports the PAdES format.
From the backend of our Viafirma Documents solution, we can configure our signature policies, requiring to add a series of evidences to the signer (images, OTP verification, etc) when he accesses the signature page. Once all the steps are completed, the document will be electronically signed and the evidences will be considered as attached files to the PDF, reinforcing even more the legality of the whole process.
For a document to be signed remotely, server-side signature is a prerequisite. This will be done automatically by uploading any valid certificate (either the corporate or the manager’s one) to the tool. Although in case of not having one, the default Viafirma certificate will be used. Once uploaded, in its configuration a drop-down menu will appear with the different PAdES signature extensions, where we will choose the one that best suits our needs.