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Digital Signatures with PDFlib PLOP DS

PDFlib PLOP and PLOP DS 5.1 – Digital Signatures in PDF – is now released. Customers can download a free trial at http://www.pdflib.com/download/plop-and-plop-ds/.

PDFlib GmbH announces the release of PDFlib PLOP and PLOP DS version 5.1.

PDFlib PLOP is a versatile tool for linearizing, optimizing, repairing, analyzing, encrypting and decrypting PDF documents. PLOP DS additionally applies digital signatures to PDF documents according to the latest standards and technologies.

The highlight of version 5.1 is the support for certificate security in PDF documents. Many further enhancements regarding digital signatures have been implemented.

PLOP 5.1 brings improvements in the following areas:

  • certificate security: encrypt a document against a set of recipients which are identified by their digital certificate
  • pCOS interface 11 for retrieving details of documents encrypted with certificate security
  • Support for signing with a Hardw
  • Support for signing with a Hardware Security Module (HSM)
  • Time-stamping according to RFC 5816
  • Optimized file size and processing time  for generating signatures
  • Support for indirect CRLs
  • Enhanced robustness of CRL retrieval
  • Improvements for multi-threaded signing
  • PAdES/CAdES signatures created by default
  • Custom build for attaching external cryptographic engine for hashing and signing

Read more about PDFlib PLOP and PDFlib PLOP DS...


PDFlib GmbH is completely focused on PDF technology. Customers worldwide use PDFlib products since 1997. The company closely follows development and market trends, such as ISO standards for PDF. PDFlib GmbH products are distributed in 100 countries all over the world with major markets in North America, Europe, and Japan….

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