METHOD AND DEVICE FOR EMBEDDING PUBLIC KEY INTO ELECTRONIC DOCUMENT, METHOD AND DEVICE TO TAKE OUT PUBLIC KEY EMBEDDED IN THE ELECTRONIC DOCUMENT, AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To embed a public key into an electronic document, such as an elec tronic mail and a home page on WWW, to which ciphering system is introduced, in a compact form, rather than in the case of employing a conventional public key represented by a dry and uninspired long character string and to take out the key from the document. SOLUTION: A public key, embedded into electronic document device, and a public key taking out from electronic document device are constituted of each function of an input section 11, a public key embedding section 12, a public key taking out section 13, an output section 14 and a display section 15. The public key is not added to an electronic document as a character string, but rather the public key is embedded into an image as watermark information and the image, to which the key is embedded, is added to the document. The image is made into two or three-dimensional image icons, so that the public key is made into a familiar and compact form for a beginner.