In case of modification of the drawing, the signature disappears immediately.

Publisher:	SummerCAD
Downloads:	1
Software Type:	Shareware, 58.00
File Size:	7.63M
OS:	Windows All
Update Date:	28 January, 2014

Digital Signature is not just a scanning bitmap of a handwriting signature, is not also just a bitmap vectorized. It's smart, it's base on PKI. It's SmartSignSafty For AutoCAD.
First, look at the signature by a traditional pen on paper, and your purpose is nothing more than 'Trust' and 'Responsibility'. As your signature is accepted, the content of the document paper has been accepted too, and you have the responsibility for the content.
A service that provides a proof of the integrity and origin of data.
An authentication that can be asserted to be genuine with high assurance.
Digital Signature is the same as the properties of tamper-proofing, anti-clone and non-repudiation of disputed charges.
The purpose of signature:
Tamper-proofing: using digital signature can help you to identify the documents are original, and not unauthorized modified.
Anti-clone: you digital signature is not like a bitmap, and it cannot be copied. The digital signature is a string encrypted using Pubic Key Infrastructure, and it's composed by your certificate, and document contents. Access to the public key does not enable a fraudulent party to fake a valid signature.
Non-repudiation: an entity that has signed some information cannot later deny having signed it.
Advantages of SmartSignSafty:
1. With the properties of tamper-proofing, anti-clone and non-repudiation.
2. Smart. In case of modification of the drawing, the signature disappears immediately.
3. Visualization. Like the traditional handwriting signature, it can be displayed and plotted.