SIP 301 Moved Permanently vs 401 Unauthorized
SIP 301 (Moved Permanently) is a 3xx Redirection response, while 401 (Unauthorized) is a 4xx Client Failure response. 301 indicates that the user can no longer be found at the address in the Request-URI. The client should direct future requests to the new address in the Contact header. In contrast, 401 means that the request requires user authentication. The response includes a WWW-Authenticate header with a challenge for the realm.
Description
The user can no longer be found at the address in the Request-URI. The client should direct future requests to the new address in the Contact header.
When You See It
When a user has permanently changed their SIP address. All future calls should be directed to the new URI.
How to Fix
Update your address book or routing tables to use the new Contact URI provided in the response.
Description
The request requires user authentication. The response includes a WWW-Authenticate header with a challenge for the realm.
When You See It
When making a request that requires Digest authentication. Common for REGISTER and INVITE requests to authenticated SIP trunks.
How to Fix
Resend the request with proper Authorization header containing valid credentials (Digest authentication).
Key Differences
301 is a 3xx Redirection response, while 401 is a 4xx Client Failure response.
SIP 301: The user can no longer be found at the address in the Request-URI. The client should direct future requests to the new address in the Contact header.
SIP 401: The request requires user authentication. The response includes a WWW-Authenticate header with a challenge for the realm.
You encounter 301 when when a user has permanently changed their SIP address. All future calls should be directed to the new URI.
You encounter 401 when when making a request that requires Digest authentication. Common for REGISTER and INVITE requests to authenticated SIP trunks.
When to Use Which
For 301 (Moved Permanently): Update your address book or routing tables to use the new Contact URI provided in the response. For 401 (Unauthorized): Resend the request with proper Authorization header containing valid credentials (Digest authentication).