> For the complete documentation index, see [llms.txt](https://doc.peeringhub.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.peeringhub.io/guides/generating-certificate/acme-protocol-reference/get-nonce.md).

# Get nonce

JWS header must contain a fresh nonce, received from the ACME server. Each nonce value can be used only once, and only within a limited period of time (usually 1 hour). To acquire a new nonce value, send a HEAD or a GET request to the newNonce URL. ACME server shall return an empty response with a newly generated nonce string in a Replay-Nonce header.

```
HEAD https://stica.peeringhub.io/acme/new-nonce

HTTP/1.1 200 OK
Replay-Nonce: ABECF2EDB773493ABC9C6E000420DBEC
Content-Length: 0
```

ACME server should generate a fresh nonce value in reply to every HTTP request, described in this document. The new nonce value should be included into Replay-Nonce header.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://doc.peeringhub.io/guides/generating-certificate/acme-protocol-reference/get-nonce.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.