docs for static IP ranges (#830)

Author: bryantanderson

fern/docs.yml

@@ -689,6 +689,8 @@ navigation:
                 path: security-and-privacy/PCI.mdx
               - page: Proxy server guide
                 path: security-and-privacy/proxy-server.mdx
+              - page: Static IP addresses
+                path: security-and-privacy/static-ip-addresses.mdx
               - link: SOC-2 Compliance
                 href: https://security.vapi.ai/
           - section: Legal

fern/security-and-privacy/static-ip-addresses.mdx

@@ -0,0 +1,46 @@
+---
+title: Static IP addresses
+subtitle: Whitelist Vapi IP addresses 
+slug: security-and-privacy/static-ip-addresses
+---
+
+
+## Introduction to Vapi static IP addresses
+
+Vapi supports static IP addresses for outbound HTTP requests. When enabled, all HTTP requests from Vapi to your server will originate from a fixed set of IP addresses, allowing you to configure strict firewall rules and network security policies.
+
+## Why use static IP addresses
+
+Static IP addresses provide an additional layer of security for your infrastructure by allowing you to:
+
+- **Control network access** - Restrict incoming traffic to only trusted sources
+- **Simplify firewall rules** - Define precise IP based access controls
+- **Meet compliance requirements** - Satisfy security policies that mandate IP whitelisting
+- **Audit traffic sources** - Verify that requests are genuinely from Vapi's infrastructure
+
+## Vapi's static IP addresses
+
+When static IP addressing is enabled, all webhook requests from Vapi will originate from the following CIDR block:
+
+- `167.150.224.0/23`
+
+## Enabling static IP addresses
+
+You can enable static IP addressing through the server object
+
+### Example
+
+```json
+{
+  "serverUrl": "https://your-server.example.com/webhook",
+  "staticIpAddressesEnabled": true
+}
+```
+
+<Warning>
+Always test static IP configuration in a staging environment before deploying to production to avoid service disruptions.
+</Warning>
+
+## Need help?
+
+If you have questions about static IP addressing, contact our support team at support@vapi.ai.