Secure Time Stamp Authority (TSA)

ADSS TSA Server provides independent and irrefutable proof of time for transactions, documents and digital signatures. It can be used to create legal weight evidence that business transactions occurred at a defined moment in time, that e-documents existed at a particular time and that they have not been subsequently altered. It can also independently prove when a digital signature was applied by the signer so that its validity can be verified in the long-term, even after expiry or revocation of signer’s digital credentials.


ADSS TSA complies with the IETF RFC 3161 and RFC 5816 specifications and can be used for internal TSA needs or to provide infrastructure-class commercial TSA services to multiple external parties. It offers a number of advantages for managed service providers in the authentication, logging/reporting and token management features. ADSS TSA Server also supports ETSI EN 319 422 time stamping profile and ETSI EN 319 421 policy requirements for time stamping authorities.

Features & Benefits

Multiple TSA profiles

Set-up multiple virtual TSA servers all from the same physical machine with easy central management console, and lower total cost of ownership when compared to having separate TSA servers with dedicated hardware and software costs. Each TSA profile can use different TSA policies, perhaps with different time accuracies and TSA signing keys.

Product certifications

Often business applications already have an established Know Your Customer (KYC) registration process. Such business applications can act as very effective Registration Authorities (RAs) and easily integrate with ADSS CA Server using configurable registration and certification processes.

RFC 3161/5816 timestamps support

RFC 3161 and RFC 5816 are the definitive standard for secure cryptographic timestamping. ADSS TSA Server has been independently tested for compliance against this specification. It has been widely tested with a range of 3rd party timestamp client applications.

Key points

>> RFC 3161/5816 compliant TSA services

>> Supports Microsoft Authenticode timestamps

>> Security management is CWA 14167-1 certified allowing Qualified TSA service to be provided