What is a PAdES signature?

PAdES signature is a digital signature format for PDF files. It is the securest way to sign PDF or Word documents electronically online.

How to e-sign PDF documents online?

Upload PDF document

Click Create new > Document. Choose your PDF file to upload and will be displayed in our document preview.

Add signature fields to PDF

Once PDF document is uploaded, simply drag and drop signature fields on it and assign them to signers by adding signer emails.

Sign PDF document online

Once the PDF document is ready for signing click on the Sign button and your secure digital signature will be added.
Now you can download a signed version of the file or share it over Agrello platform.

What it means to create a digital signature?

Before diving into PAdES format, lets recap what is a digital signature.

A digital signature is a mathematical technique for validating the authenticity and integrity of a message, piece of software, or digital document. It's the digital equivalent of a handwritten signature or a stamped seal, but it's far more secure. A digital signature is designed to prevent tampering and impersonation in digital communications.

Digital signatures can be used to verify the origin, identity, and status of electronic documents, transactions, or digital messages. They can also be used by signers to acknowledge informed consent.

Digital signatures are legally binding in many countries, including the United States, in the same way that traditional handwritten document signatures are.

How do digital signatures function?

Public key cryptography, also known as asymmetric cryptography, underpins digital signatures. Two keys are generated using a public key algorithm, such as RSA (Rivest-Shamir-Adleman), resulting in a mathematically linked pair of keys, one private and one public.

Digital signatures are created using two mutually authenticating cryptographic keys in public key cryptography. The person who creates the digital signature encrypts signature-related data with a private key, and the only way to decrypt that data is with the signer's public key.

If the recipient is unable to open the document using the signer's public key, there is a problem with the document or the signature. Digital signatures are authenticated in this manner.

What is the difference between digital signature and electronic signature?

Although the terms electronic signature and digital signature are frequently used interchangeably, the two concepts are distinct. The primary distinction between the two is that a digital signature is used to protect documents and is certified by certification authorities, whereas an electronic signature is frequently associated with a contract that the signer agrees to. 

A digital signature is a unique digital characteristic, similar to a fingerprint embedded in a document. To be associated with the document, the signer must have a digital signing certificate. The digital signing certificate is issued by the certification authority.

It's similar to a driver's license or a passport. A digital certificate aids in determining whether or not a document has been tampered with. It is essential for identity verification.

A digital signature is also used to protect digital documents, which is an important feature. Fraudsters can forge documents to submit online using an electronic signature, but it is nearly impossible with a digital signature. Only an authorized person can view the electronic document and make changes or edits.

When a digital signature is used on a document, the digital certificate is linked to the signed data in a single, unique fingerprint. Because these two components of a digital signature are distinct, they are more practical than wet signatures because their origin can be verified. This cryptographic operation facilitates the following actions:

  • demonstrating the document's authenticity and source
  • ensuring that no changes were made to the document after signing
  • confirming the signer's identity.

An electronic signature is any electronic symbol, process, or sound associated with a record or contract that the interested party intends to sign, according to US law. Thus, the intention to sign a document or agreement is the primary feature of an electronic signature. Another distinction between an electronic signature and a digital signature is that an electronic signature can be oral, a simple mouse click, or any other electronic authorization.

An electronic signature's main feature is that it reveals the signer's intent to sign the document. It usually complies with contracts or other agreements made by two parties. As previously stated, there are various types of electronic signatures. They become legally binding once all parties have shown their commitment to enter into a particular contract.

Another benefit of an electronic signature is that it assist in document authenticity verification.

The parties involved should be able to be identified once it has been signed. However, because there is no digital certificate, it can be difficult to verify an electronic document.

Another distinguishing feature of an electronic signature is that it is used to execute a contract. In a contract, for example, two people usually agree to perform certain obligations. If both parties sign this agreement, it becomes legally binding. You can use an electronic signature in this case. Furthermore, because they are simple to use, electronic signatures are frequently used in contracts.

To sum up - digital signatures are more secure electronic signatures as they make the signers more easily identifiable and ensure that the document has not been dampered after signing. So we can use both terms, but bare in mind that not all e-signatures are digital signatures.

What is PAdES signature?

PAdES is an acronym that stands for PDF Advanced Electronic Signatures. It is a technical standard that refers to a set of extensions and restrictions used when signing PDF documents electronically.

One significant advantage of PAdES is that electronically signed documents can remain valid for long periods of time even if the underlying cryptographic algorithms are compromised. Regardless of technological or other advances in the future, it must be possible to validate the document to confirm that the signature was valid at the time it was signed - a concept known as Long-Term Validation.

ETSI published the PAdES technical specification (European Telecommunications Standards Institute). When applying digital signatures to documents, PDF is one of the most commonly used formats. Thus, the concept of the digital signature was introduced in PDF 1.3 (1999), and it was refined in subsequent versions.

Above all, digital signatures are essential in corporate document workflows. The emphasis here is on digital release, acceptance, and approval processes, as well as contract signing. As a result, digital signatures and standards have come to occupy a large space in the business world and are extremely important, particularly in terms of digital document archiving and security. While no specific PDF signature format had previously been defined, it was still possible to visualize digital signatures using graphical and textual elements.

Since version 1.3, it is also part of the PDF specification how to include a signature, which PDF objects are involved and what exactly is the scope of the signed area in the PDF.

What are the benefits of PAdES?

One significant advantage of PAdES is that documents signed electronically in this manner are valid for a long time, even if the underlying algorithms fail.
PAdES recognizes the importance of archiving digitally signed documents for many years. The signature on the document must be verifiable at any time in the future. This is known as Long-Term Validation (LTV).

PAdES also has the advantage of not requiring any additional software. Existing programs can easily use it. The document can be read using a PDF reader, and more advanced PDF readers can also display the signature information.

The PDF document contains the signature information. This ensures that you have everything you need.

Are electronic signatures allowed by law? Absolutely.

In many countries around the world, electronic signatures are legal, trusted, and enforceable. While laws differ, Agrello provides the most flexibility in a single global e-signature solution. You can choose the right type for each use case ranging from simple e-signatures to e-signatures with strong identification to highly secure, regulated digital signatures in the cloud.

Many countries around the world accept e-signature as evidence in court. Certain highly secure, regulated digital signatures are frequently regarded as equivalent to an ink signature.

In the United States, the E-Sign Act and the Uniform Electronic Transactions Act (UETA) established the legal framework for the use of e-signature across all states.

The Electronic Identification and Trust Services Regulation (eIDAS) created legislation in the European Union that helped standardize e-signature status across national borders.

If you use Agrello, is your document secure?

Agrello has made significant investments in cyber security and complies with US, EU, and international security practices.