What is the difference between drmz and drmx files?
PDF documents can be encrypted by Drumlin in one of two ways:
(i) .drmx files are generated using Rijndael 256bit two-part key encryption of the PDF and the header block (separately encrypted) and then encapsulated within a proprietary wrapper. .drmx files are extremely strongly encrypted, but have higher processor overheads, so are only available for use on PCs and Mac computers at present. Authorization codes for .drmx files are 20 characters long, so need the copy/paste mechanism or .dac files to enter the code without a lot of typing. The .drmx file format can be read by Javelin3 for PC, Javelin3Pro for PC and Javelin for Mac, plus Drumlin itself as a reader. These files cannot be read by mobile devices, so if very strong security is required with mobile devices not supported, then .drmx can be a good option. Because it uses a split key system care should be taken when updating these files, because if the same source PDF filename is used then the same documentID record will be assigned as default, but with a new random key. This means that previously issued versions of the document cannot be authorized once a new version has been generated. This does not happen with .drmz files as they do not use a split-key system. It is recommended that if you decide to use drmx format files, new versions are issued as new documents, i.e. if the original PDF file was myfile.pdf, then for an update/new version (even with permission changes only) then start with a new name for the source file, e.g. myfile1.pdf, and then the service will assign a new documentID to the file. This will avoid problems with different encryption keys between updates.
(ii) .drmz files can be read using Javelin on all platforms, desktop/laptop and mobile devices. Because mobile devices have more limited processing power and simple memory allocation we use a one-part proprietary encryption/encoding system, with the same structure as the .drmx file, i.e. with the PDF separately encrypted from the header block and then encapsulated in our .drmz file format.For most purposes .drmz files are the recommended format to use. drmz files can be updated and used to replace an existing file without any encryption related issues.
We would describe the .drmz format as commercial-level security for cross-platform usage whilst the .drmx format as industrial or military strength