Getting started

CNX's TSA has two kinds of endpoint — see Endpoints for the full comparison:

• free.tsa.cnx.net.kh — self-service, no registration. Use this to evaluate the service or for informal, non-contractual use.
• A subscriber endpoint (<your-org>.tsa.cnx.net.kh) — authenticated, keeps a retained history of issued tokens with CNX acting as witness of record. Provisioning requires CNX to bind your authentication method — contact noc@cnx.net.kh to set one up.

Making a first request

A timestamp request sends a hash of your data, not the data itself. This function hashes a file with SHA-256 and posts an RFC 3161 query to the free endpoint, writing the response token alongside the original file:

stamp() {
  openssl ts -query -sha256 -data "$1" -no_nonce \
    | curl -s -H "Content-Type: application/timestamp-query" \
        --data-binary @- https://free.tsa.cnx.net.kh/ \
    > "$1.tsr"
}

stamp report.pdf

report.pdf.tsr is the timestamp token. See Request and token format for what it contains, and Verifying a timestamp to check it independently.