HTTP 101 Switching Protocols vs 103 Early Hints
Both HTTP 101 (Switching Protocols) and 103 (Early Hints) belong to the 1xx Informational category. 101 indicates that the server understands the Upgrade header field request and indicates which protocol it is switching to. Meanwhile, 103 means that used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.
Описание
The server understands the Upgrade header field request and indicates which protocol it is switching to.
Когда вы это видите
When upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
Как исправить
This is normal behavior during protocol upgrades. Ensure your client supports the target protocol.
Описание
Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.
Когда вы это видите
When a server wants the browser to start loading CSS/JS before the full response is ready.
Как исправить
No fix needed. This optimization helps speed up page loading.
Ключевые различия
HTTP 101: The server understands the Upgrade header field request and indicates which protocol it is switching to.
HTTP 103: Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.
You encounter 101 when when upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
You encounter 103 when when a server wants the browser to start loading CSS/JS before the full response is ready.
Когда что использовать
For 101 (Switching Protocols): This is normal behavior during protocol upgrades. Ensure your client supports the target protocol. For 103 (Early Hints): No fix needed. This optimization helps speed up page loading.