> ## Documentation Index
> Fetch the complete documentation index at: https://docs.provenlog.com/llms.txt
> Use this file to discover all available pages before exploring further.

# RFC 3161 Timestamping

> Third-party proof that records existed at a given time

RFC 3161 timestamping proves to any third party that your audit records existed at a particular time — not just that they're internally consistent.

## How it works

`plog timestamp` signs the current [Merkle root](/concepts/merkle-trees) with an RFC 3161 Timestamp Authority (TSA). The TSA returns a signed timestamp token that can be independently verified.

One signature covers all events across all chains — the Merkle root represents the entire audit trail.

## Usage

```bash theme={null}
# Request a timestamp from the default TSA (freetsa.org)
plog timestamp

# Use a custom TSA
plog timestamp --tsa-url https://your-tsa.com

# List stored timestamps
plog timestamp --list

# Verify the latest timestamp against current state
plog timestamp --verify
```

## API

```bash theme={null}
# Request a timestamp
curl -X POST http://localhost:7600/v1/timestamp

# List timestamps
curl http://localhost:7600/v1/timestamps

# Verify latest
curl http://localhost:7600/v1/timestamps/verify
```

## What it proves

| Without timestamping             | With timestamping                          |
| -------------------------------- | ------------------------------------------ |
| Events are internally consistent | Events provably existed at a specific time |
| Hash chain is valid              | Third-party attestation of the Merkle root |
| Self-attested integrity          | Independent temporal proof                 |

## Storage

Timestamps are stored with their certificate chain for offline verification. Each timestamp references the Merkle root it was created from, allowing you to prove the state of the audit trail at any point in time.