trusted-timestamp

In my build process, I want to include a timestamp from an RFC-3161-compliant TSA. At run time, the code will verify this timestamp, preferably without the assistance of a third-party library. (This is a .NET application, so I have standard hash and asymmetric cryptography functionality readily at my disposal.) RFC 3161, with its reliance on ASN.1 and X.690 and whatnot, is not simple to implement, so for now at least, I'm using Bouncy Castle to generate the TimeStampReq (request) and parse the TimeStampResp (response). I just can't quite figure out how to validate the response. So far, I've

If I set a timestamp with signing, what happens? What if I don't set? Is it essential? Why is it recommended? Timestamping is used to specify time when the digital signature is made. This is needed to properly validate the signature. If signature timestamp is present, the application which validates (verifies) the signature, will check whether the certificates involved into signature validation were valid at the moment of signing. If there's no timestamp for the signature, certificate validity is checked for the moment of signature validation, which is not always acceptable. Example:

Would like to know if anybody knows any free(trial) time-stamp server service. I would like to test time stamping features in itext. Like I used Start Com class 1 as free CA for testing purposes. Hope I made it clear. Hoping someone knows a place Thanks jnm2 You can try one of these publicly accessible RFC 3161 compliant time-stamping services: https://freetsa.org Supports HTTP, HTTPS and TCP transports and has other features http://time.certum.pl http://dse200.ncipher.com/TSS/HttpTspServer http://tsa.safecreative.org 5 free requests per day (may not be valid as root CA is 'test') - Safe