TimeStamp service (Chronological Validation) uses Public Key Infrastructure and reliable time sources to provide reliable timestamps, according to international standards.
The purpose of time-stamping service is to provide timestamps used as support for electronic signatures, as Directive 1999/93 / EC of the European Parliament and of the Council of 13 December 1999, the Law 290-D / 99 and other applicable national legislation.
Nevertheless, the time stamps may also be used for any other purpose which requires proof that certain data existed at a certain date / time.
The time stamps issued by DigitalSign, respect and implement the following standards:
- ETSI TS 102.023: Electronic Signatures and Infrastructures (ESI); Policy requirements for time-stamping authorities
- RFC 3628: Requirements for Time-Stamping Authorities
The Policy and Time Stamping Certification Practice and Certification Practice Statement (CPS) from DigitalSign, can be found at: http://www.digitalsign.pt/en/dpc
To obtain a timestamp, you must make a request to a timestamps server (Time Stamping Server). This server, after receiving a request, generates a timestamp (signed) with the current date and legal time.
The Time Stamping service allows you to certify the date and time that any type of electronic document was signed, so that the user can prove its integrity, authenticity and authorship.
This stamp certifies the accuracy of the time and date of the application / document, but also the integrity and non-repudiation of content. The date / time provided by the time-stamping service, is the Portuguese Current time which is provided by the Astronomical Observatory of Lisbon (OAL).
DigitalSign, is a Portuguese entity accredited for issuing timestamps. See here the relationship (Trusted-Service Status List 7.2 - Page 40) of Certifying Entities that are accredited or registered by the Accreditation Authority (http://www.gns.gov.pt/gns/pt/tsl/).
Technological Solution Certifications
The Time Stamping Service from DigitalSign, has as technological solution the ADSS system (Advanced Digital Signatures Services).
The ADSS has been assessed and certified by the National Security Authority (http://www.gns.gov.pt/assinatura-electronica.aspx) under the security requirements defined in document CWA 14167-1 - "Security Requirements for Trustworthy System Managing Certificates for Electronics Signatures".
High Availability Solution
DigitalSign, given the criticality of Time Stamping service, implemented this service at its Data Center in Guimarães, and has the same solution in redundancy in the data center of British Telecommunications in Lisbon, for the purpose of disaster recovery and Load Balancing.