Time stamping is a technique used to prove the existence of certain digital data prior to a specific point in time. With the recent development of electronic commerce, time stamping is now widely recognized as an important technique used to ensure the integrity of digital data for a long time period. Various time stamping schemes and services have been proposed. When one uses a certain time sta...

electronic document existed at a certain point in time and that it has not been modified since then. Different time-stamping schemes have already been proposed. Most of them use the concept of trusted Time-Stamping Authority (TSA). A TSA is in charge of time-stamping documents and delivering a timestamping certificate for each time-stamped document. The purpose of this paper is to propose a new...

Metal stamping die design is a complex, experiencebased and time-consuming task. Various artificial intelligence (AI) techniques are being used by worldwide researchers for stamping die design to reduce complexity, dependence on human expertise and time taken in design process as well as to improve design efficiency. In this paper a comprehensive review of applications of AI techniques in manuf...

Efficient secure time-stamping schemes employ a 2-level approach in which the time-stamping service operates in rounds. We say that a time-stamping service is accountable if if it makes the TSA and other authorities accountable for their actions by enabling a principal to detect and later prove to a judge any frauds, including attempts to reorder time-stamps from the same round. We investigate ...

This study deals with the cumulative pitch variations in DIN male contacts. A connector provides a separable interface between two subsystems of an electronic system. DIN is a series of connector which stands for Deutsch Institut fur Normung. They are used for applications like switching, transmission, radio base stations, control units and machines. Connector manufacturing involves stamping, m...

The Internet and World Wide Web (WWW) are evolving as an important communication technology. This paper aims to develop methodology for enabling better concurrent stamping part and die development, in the evolving Web technology. The characteristics of concurrent stamping part and die design are presented, and the necessity and feasibility of building Web-based concurrent stamping part and die ...

4 Implementation 9 4.1 Time-stamping Algorithm . . . . . . . . . . . . . . . . . . . . . . 9 4.2 Correctness of the Implementation . . . . . . . . . . . . . . . . . 11 4.2.1 Preliminary Results . . . . . . . . . . . . . . . . . . . . . 11 4.2.2 Proofs of Safety Conditions . . . . . . . . . . . . . . . . . 12 4.3 Progress Condition . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4.3.1 Pro...

This paper describes a new electronic official seal stamping based on Group Signature, USB Key. Bill/Contract in Ecommerce must be seal stamped to gain tamper proof and nonrepudiation. The seal stamping control is designed based on the certificate-based public key. This technique is more efficient for generating and verifying individual/group signatures in terms of computational efforts and com...

We discuss the availability questions that arise when digital time stamps are used for preserving the evidentiary value of electronic documents. We analyze the time-stamping protocols known to date and point out some weaknesses that have not been addressed so far in scienti c literature. Without addressing and solving them, any advantage of the linkage-based protocols over the hash-and-sign tim...

This paper describes the results of a research activity conducted cooperatively by an academic and an industrial party. It presents a practical solution for and an experience in the implementation of time stamping services and their exposition to the Internet for inter-enterprise integration. State-of-the-art time stamping algorithms and crucial issues related to their practical implementation ...