Abstract: A distributed digital certificate validation method of a client connectable in communication with a host is provided. A first connection is made with the host to establish data communication with the host. A request for a certificate validation result is sent to the host. A file containing at least the requested certificate validation result is imported from the host and the imported file is stored locally for later retrieval of at least the requested certificate validation result.

Abstract: A method of validating a digital certificate comprises retrieving from a first data store a digital certificate, retrieving from a second data store a plurality of certificate revocation lists (CRLs), and selecting one of the plurality of CRLs to validate the digital certificate as of a date which is before the current date.

Abstract: A system for handling files containing digitized images, such as digitized bank checks. Four digitized image-files are obtained for each check: front and back at the beginning of a process, and front and back at the end of the process. Four digital signatures are generated, one for each image-file. The four image-files are to be consolidated into a single composite file. However, for technical reasons, the content of the image-files must be altered somewhat. Thus, if the image-files are later extracted from the composite file, the extracted files will not correspond to the original image-files, and will produce different digital signatures. The invention allows the original image-files to be accurately extracted from the composite file.

Abstract: A distributed digital certificate validation method of a client connectable in communication with a host is provided. The method comprises making a first connection with the host to establish data communication with the host, sending to the host a request for a certificate validation result, importing from the host a file containing at least the requested certificate validation result, and storing the imported file locally for later retrieval of at least the requested certificate validation result.

Abstract: A method of validating a digital certificate comprises retrieving from a first data store a digital certificate, retrieving from a second data store a plurality of certificate revocation lists (CRLs), and selecting one of the plurality of CRLs to validate the digital certificate as of a date which is before the current date.

Abstract: A modified multi-page TIFF file. A Tagged Image Format File (TIFF) conforms to a published standard. The TIFF file contains an initial header, which contains a pointer to another header, which points both to (1) the first graphical image and (2) a second header. The second header points to both (1) the second image and (2) a third header, and so on. The headers allow a TIFF reader to locate any selected graphic image, and display it. The invention interleaves auxiliary information within the TIFF file, for example, between a header and a graphical image. The auxiliary information does not interfere with the TIFF reader, and the TIFF reader does not detect the auxiliary information.

Abstract: A signal extraction and character recognition system is provided for an MICR system using E13B font characters and a magneto-resistive read head. Each character is treated as defining a block comprising a matrix of equal sized zones. Because adjacent characters are separated by space (e.g., non-residually magnetized regions), the read head output signal is used to first identify the start of each character. As the document bearing the characters moves relative to the head, the signal strength from each vertical zone is summed. The relative vertical column signal strength is then compared to the vertical column signal strength for the preceding column to form a ratio set. The ratios are then quantized into one of three levels, depending upon whether R>T.sub.1 (a first threshold, preferably 4/3), R<T.sub.2 (a second threshold, preferably 3/4), T.sub.2 .ltoreq.R.ltoreq.T.sub.1. The patterns of these three quantized levels uniquely identify the 14 characters in the E13B character set.

Abstract: A method for locating the start of a MICR character in E13B font so as to facilitate character recognition. A Calculated Character Start Position (CCSP) is generated by using a predetermined number of voltage samples corresponding to a portion of MICR waveform generated by reading a MICR character on a document. The CCSP is generated by averaging the predetermined number of voltage samples within the window which tends to minimize the harmful effects of noise. Noise from magnetic ink spatter is sometimes wrongly interpreted as the start of a character. A process of "jiggling" is used to assist character recognition techniques by utilizing different character start positions to determine whether or not a template match in character recognition techniques occurs when the new or different character start position is used.

Abstract: A method and system for use in reading magnetic characters comprised of bars and intervals dimensioned as short intervals or long intervals as is done in CMCs7 encoding. The interval between adjacent bars of a character is obtained by calculating the zero crossing point between a peak of a first polarity and a peak of a second polarity associated with a "bar" in the associated scanning signal. The zero crossing point may be compared to the midpoint of the associated "bar". The intervals are then determined by obtaining the distance or interval between the zero crossing points of adjacent "bars".