SIP 300 Multiple Choices vs 420 Bad Extension
SIP 300 (Multiple Choices) is a 3xx Redirection response, while 420 (Bad Extension) is a 4xx Client Failure response. 300 indicates that the address in the request resolved to several choices, each with its own location. The user or UA can select a preferred communication endpoint. In contrast, 420 means that the server did not understand the protocol extension specified in a Require or Proxy-Require header. The Unsupported header lists the unknown extensions.
Descrição
The address in the request resolved to several choices, each with its own location. The user or UA can select a preferred communication endpoint.
Quando você o vê
When a user has multiple registered devices or contact addresses and the server cannot determine which one to use.
Como corrigir
Select one of the provided Contact addresses and resend the request to that specific URI.
Descrição
The server did not understand the protocol extension specified in a Require or Proxy-Require header. The Unsupported header lists the unknown extensions.
Quando você o vê
When the request includes a Require header with SIP extensions that the server does not support.
Como corrigir
Check the Unsupported header in the response. Remove the unsupported extension from the Require header or make it optional via Supported.
Diferenças principais
300 is a 3xx Redirection response, while 420 is a 4xx Client Failure response.
SIP 300: The address in the request resolved to several choices, each with its own location. The user or UA can select a preferred communication endpoint.
SIP 420: The server did not understand the protocol extension specified in a Require or Proxy-Require header. The Unsupported header lists the unknown extensions.
You encounter 300 when when a user has multiple registered devices or contact addresses and the server cannot determine which one to use.
You encounter 420 when when the request includes a Require header with SIP extensions that the server does not support.
Quando usar qual
For 300 (Multiple Choices): Select one of the provided Contact addresses and resend the request to that specific URI. For 420 (Bad Extension): Check the Unsupported header in the response. Remove the unsupported extension from the Require header or make it optional via Supported.