Signature Cells

A cell that represents a model signature is called a "signature cell." It is created and managed as a normal cell in a cell library and then placed in the model that is being signed. What makes a signature cell special is that it is digitally signed. Digitally signing the cell prevents tampering and associates a digital certificate with the cell. Internally, a signature cell contains an embedded cell, which is the cell’s (hidden) signature.

Signature Cell Structure
Cell <John Doe>
Graphics (OLE, text, etc.) Orphan Cell Header (signature linkage)

Signature Cell Structure

Cell <John Doe>

Graphics (OLE, text, etc.)

Orphan Cell Header (signature linkage)

This method of associating a certificate with cell graphics reduces errors in placing signature cells but does not make signature cells more or less secure or trustworthy.

Note: When creating a signature cell, set the current level to default and place all its elements on the default level. This ensures that placing a signature cell will not break existing signatures.