---
title: Protocol validation rules
description: Protocol validation rules for network traffic.
image: https://developers.cloudflare.com/zt-preview.png
---

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# Protocol validation rules

Cloudflare Network Firewall (formerly Magic Firewall) supports [Session Initiation Protocol (SIP) ↗](https://datatracker.ietf.org/doc/html/rfc2543) to inspect traffic validity and enforce a positive security model.

You can use the `sip` field when creating a rule to determine if packets are valid SIP Layer 7 (L7) protocol. Refer to [Cloudflare Network Firewall fields](https://developers.cloudflare.com/cloudflare-network-firewall/reference/network-firewall-fields/), specifically the `sip` field, for more information on this topic.

Contact your account manager if you need Cloudflare Network Firewall to support additional protocols.

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