305
SIP
305 Use Proxy
The requested resource must be accessed through the proxy given by the Contact header field.
On this page
When You See This Code
When the request must be routed through a specific outbound proxy server.
How to Fix
Resend the request through the proxy specified in the Contact header of this response.
Specification
Compare With
Guides
401 Unauthorized vs 403 Forbidden: When to Use Each
Security & Authentication
SIP Response Codes: Understanding VoIP Call Flow
Real-Time Protocols
SIP Call Flow: Understanding Session Setup
Real-Time Protocols
WebRTC Signaling with SIP and WebSocket
Real-Time Protocols
RFC 3261: SIP Protocol Deep Dive
Protocol Deep Dives
TLS 1.3: Faster, Simpler, More Secure
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TLS Versions
Frequently Asked Questions
What is SIP 305 Use Proxy?
The requested resource must be accessed through the proxy given by the Contact header field.
When do you see SIP 305 Use Proxy?
When the request must be routed through a specific outbound proxy server.
How to fix SIP 305 Use Proxy?
Resend the request through the proxy specified in the Contact header of this response.