electronic signer whitepaper

White Paper – Electronic Signer

The Electronic signerThe electronic signer application offers all the neccesary features to sign documents. To serve a broad as possible market, the Portable Document Format (PDF) was chosen as the document format for use with the electronic signer. Both the “classical” manual handwritten signature and digital signature may be used to sign documents. It is also possible to add other electronic fields in a document such as a date field, read and understood etc.

Signing with an electronic PenWhen using the electronic signer on a Tablet PC or using a specific signing device connected to the PC, documents can be signed by hand using the stylus. The look and feel of this signing process is identical to signing the paper version. Drawing the signature is only allowed on predefined fields on the document. These fields are indicated by standard PDF form fields, which can be added by LetterGen during the document creation. When saving the document, the signatures are embedded into the PDF document. For workflow process reasons, signature fields not signed in a previous step remain available for signing in a next workflow step.

On the PDF document the signature area will show as follows:

After signing, the signature will be integrated in the PDF document.

White Paper - Electronic Signer (2009-06-04) P. 1/6BTR Services NV www.LetterGen.com

A sample signing workflow with the electronic Pen

(1) Create a PDF document with text fields that have an identifier that starts with #SIG# (manual signature) or #TXT# (manual text field).

(2) Visualization of the document in the PDF SignControl. The inkPicture control floats above the text fields in the PDF document.

(3) The user can sign or write a text in the inkPicture control.(4) The signatures/texts will be saved in the output PDF document.


S/T S/T S/T S/T I I

+

I I

=

I IS/T

Original documentS/T = Signature/Text field

Type: PDF

S/T = Signature/Text field I = inkPicture control Document to signI = InkPicture control

Type: PDFSignControl

1 signatureI = InkPicture control


OuputSignature - S/T = Signature/Text

fieldType: PDF

(1) (2)

(3)(4)

Digitally signing with the eID or DIGIPASS CertiIDAn electronic signature is a legally recognized electronic tool, that indicates that a person accepts the contents of an electronic message or document.

Digitally signing of documents is based on Public Key Infrastructure. By means of PKI based smartcards, such as the Belgian eID, or a DIGIPASS CertiID from VASCO, the electonic fingerprint of the document is being signed by a 1024 bit RSA key resulting in a digital signature. Along with this signature a certificate (X509) is added to the document to provide the identity of the signer. The combination of the signature and the certifcate delivers non-repudiation proof of the identity of the signer as well as authenticity of the signed document. Since the signed document is fully PDF compliant both the document and the signatures can be displayed and validated by a viewer using Acrobat Reader.

Any user that modifies and saves the document after it has been electronically signed, will invalidate the electronic signature(s).

On the electronic signer the signing field will be shown as hereunder.

Once the signature is saved it will show in a viewer like Acrobat Reader as follows. Also when printed, the signature will be shown in the document, assuring the signatory's identity and document integrity.


A sample signing workflow using the eID or DIGIPASS CertiID

(1) Create a PDF document with text fields that have an identifier that starts with #SIG# (eID or DIGIPASS CertiID signature).

(2) Visualization of the document in the PDFSignControl. The panel control floats above the text fields in the PDF document.

(3) The user can sign in the panel control by clicking on the control. A popup lights up where the user can enter his PIN code. After the user has signed, an image shows up on the panel.

(4) All signature fields are signed.Remark: Before the signatures on the PDFSignControl will be saved in the PDF document there will be a check if every signature field is signed. (optional)

(5) The signatures will be saved in the output PDFdocument.


S S S S P P

+

P P

=

P P

Original documentS = Signature field

Type: PDF

S = Signature field P = Panel Document to signP = Panel


1 signature imageP = Panel


OutputPDF digital signature

Type: PDF

(1) (2)

(3)(5)

All signaturesP = Panel


(4)

P P

All signatures in one sessionCheck if every field is filled in

Combination Digital Signature and handwritten textAn additional feature provided by the electronic signer are handwritten fields. These operate in exactly the the same way as handwritten signatures. These type of fields are available for documents on which for example the signer is asked to explicitly write down his signature or date for example. The User has read the document and accepts the content before signing the document. The handwritten textfield may be used in combination with manual signatures or digital signatures.

(1) Create a PDF document with text fields that have an identifier that starts with #TXT# (manual signature).

(2) Visualization of the document in the PDFSignControl. The panel control floats above the text fields in the PDF document.

(3) The user can write a text in the inkPicture control.(4) The user can write a text in the next inkPicture control.(5) The user can sign in the panel control by clicking on the control. A popup lights up

where the user can enter his PIN code. After the user has signed, an image shows up on the panel.

(6) All signature fields are signed.Remark: Before the signatures on the PDFSignControl will be saved in the PDF document there will be a check if every signature field is signed. (optional)

(7) The signatures will be saved in the output PDF document.


S S P P

+

P P

=

P P

Original documentT = Text field - S = Signature field

Type: PDF

T = Text field - S = Signature field I = InkPicture - P = Panel Document to signI = InkPicture - P = Panel


1 signature imageI = InkPicture - P = PanelType: PDFSignControl

OutputPDF digital signature

Type: PDF

(1) (2)

(5)(7)

All signaturesI = InkPicture - P = Panel


(6)

P P

All signatures in one session

T T

S S

T T I I I I

P P

(3)

I I

Manual textI = InkPicture - P = Panel


P P

(4)

I I

Manual textI = InkPicture - P = Panel


- Check if every text field is filled in- Disable every text field

I II I

Check if every field is filled in

Technical RequirementsThe electronic signer application runs as a standalone .Net 2.0 application. Most of the electronic signer's visible components can be configured using a config file. Input and output of the document may be done by supplying a filename or via transfer via stdin/stdout.

System Requirements

● Windows XP SP2 or higher● .NET runtime 2.0● Administrative rights● Smart card-reader● The Belgium Identity Card Run-time (download from

http://www.belgium.be/zip/eid_datacapture_nl.html)


http://www.belgium.be/zip/eid_datacapture_nl.html

electronic signer whitepaper

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