Digital Signature

A digital signature is a bit stream that represents a dataset or part of a dataset. It is generated by a mathematical algorithm referred to as a hashing algorithm. (See Hashing Algorithm)

The signature is generated using a key. The distribution of these keys is an organizational and logistical issue. However, companies that are certification authorities take care of this distribution.

The integrity requirement within the DICOM standard is addressed through the definition of digital signatures. Digital signatures are especially important for reports and it might be expected that DICOM structured reports will implement these. The signature themselves are stored at the end of the DICOM object, i.e. after the pixel data or SR contents, to allow for pipeline processing of the data.
Digital signatures were demonstrated at several meetings, notably the European Congress of Radiology (ECR) conference in Vienna, and public source implementations and demonstration software is available.