Cryptographically secure paper document, method for marking and method for identifying it

The invention relates to information technologies and can be used to protect paper documents from forgery.The cryptographically secure paper document contains an identification tag, made in the form of an individual image, consisting of a plurality of perforations, randomly obtained by an electric discharge process, and a digital code. The document further contains a two-dimensional barcode, which includes information about the individual image, the digital code, the content of the document, and a digital signature.The method for marking a paper document consists in applying on it the above identification tag, its scanning with a scanning and processing storage device, compressing the scanned image, introducing into the memory of the scanning and processing device the information about the identification tag and the content of the document, signing the said information with the digital signature, conversing the signed information into a two-dimensional barcode, imprinting the obtained two-dimensional barcode on the paper document next to the identification tag.The method for identifying a paper document consists in reading the two-dimensional barcode imprinted on it with the help of a scanning and processing storage device, disclosing the digital signature using the public key, obtaining the compressed information about the identification tag, identifying the paper document by comparing the information obtained as a result of reading the two-dimensional barcode and the compressed scanned image on the paper document. Inventia se refera la tehnologiile informationale si poate fi utilizata pentru protectia contra falsificarii documentelor de hârtie.Documentul de hârtie protejat criptografic contine un marcaj de identificare, executat în forma de o imagine individuala, formata dintr-o totalitate de perforatii, obtinute printr-un proces aleatoriu de descarcari electrice, si un cod numeric. Documentul mai contine un cod de bare bidimensional, care include informatie despre imaginea individuala, codul numeric, continutul documentului, precum si o semnatura digitala.Procedeul de marcare a documentului de hârtie consta în aplicarea pe acesta a marcajului de identificare sus-mentionat, scanarea acestuia cu un dispozitiv de scanare si procesare cu memorie, comprimarea imaginii scanate, introducerea în memoria dispozitivului de scanare si procesare a informatiei despre marcajul de identificare si continutul documentului, semnarea informatiei mentionate cu semnatura di