Security printing jobs incorporate variable data into explicit regions, called deterrents, which can be read later, usually by a visible spectrum imager (e.g. scanner or camera). In order to initiate a security printing job, a number of authorization steps must be performed. These include the press operator entering the username, password and, possibly, biometric information. Other identification information includes the press identifier (serial number, MAC address, etc.), timestamp, job identification number, lot number (if appropriate), SKU, manufacturer ID, etc. All of these physical security data can be used to drive aspects of the variable data printing (VDP) associated with the security VDP job. This physical security data is digested (trimmed to uniform lengths for each of the input fields, exceptions handled, etc.), concatenated into a single binary string, and digitally signed as necessary to produce the desired security and/or string length. This binary string now represents the physical security data. Next, the binary string is used to drive the security VDP data. This paper will elaborate on several approaches—scrambling, hashing, encryption, sequential XOR—used to convert physical security strings into hybridized security VDP data. The advantages of this on-ramp approach to preventing spoofing of security VDP jobs, and its advantages in brand protection and anti-counterfeiting, are then discussed.
Steven J Simske, Marie Vans, "Security On-Ramp for Variable Data Printing" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP26), 2010, pp 612 - 615, https://doi.org/10.2352/ISSN.2169-4451.2010.26.1.art00063_2