HTTP 101 Switching Protocol（协议切换）状态码表示服务器应客户端升级协议的请求（Upgrade请求头）正在切换协议。
服务器会发送一个Upgrade响应头来表明其正在切换过去的协议。
该过程在协议升级机制(Protocol upgrade mechanism)中详细描述。
101 Switching Protocol
在使用 WebSockets 时会用到协议切换。
HTTP/1.1 101 Switching Protocols Upgrade: websocket Connection: Upgrade
| Specification | Title |
|---|---|
| RFC 7231, section 6.2.2: 101 Switching Protocol | Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content |
Upgrade426 Upgrade RequiredAcceptAccept-CHAccept-CH-LifetimeAccept-CharsetAccept-EncodingAccept-LanguageAccept-PatchAccept-RangesAccess-Control-Allow-CredentialsAccess-Control-Allow-HeadersAccess-Control-Allow-MethodsAccess-Control-Allow-OriginAccess-Control-Expose-HeadersAccess-Control-Max-AgeAccess-Control-Request-HeadersAccess-Control-Request-MethodAgeAllowAlt-SvcAuthorizationCache-ControlClear-Site-DataConnectionContent-DispositionContent-EncodingContent-LanguageContent-LengthContent-LocationContent-RangeContent-Security-PolicyContent-Security-Policy-Report-OnlyContent-TypeCookieCookie2Cross-Origin-Embedder-Policy [我来译!]Cross-Origin-Opener-Policy [我来译!]Cross-Origin-Resource-PolicyDNTDPRDateDevice-MemoryDigestETagEarly-DataExpectExpect-CTExpiresFeature-PolicyForwardedFromHostIf-MatchIf-Modified-SinceIf-None-MatchIf-RangeIf-Unmodified-SinceIndexKeep-AliveLarge-AllocationLast-ModifiedLinkLocationNEL [我来译!]OriginPragmaProxy-AuthenticateProxy-AuthorizationPublic-Key-PinsPublic-Key-Pins-Report-OnlyRangeRefererReferrer-PolicyRetry-AfterSave-DataSec-Fetch-Dest [我来译!]Sec-Fetch-ModeSec-Fetch-Site [我来译!]Sec-Fetch-User [我来译!]Sec-WebSocket-AcceptServerServer-TimingSet-CookieSet-Cookie2SourceMapHTTP Strict Transport SecurityTETiming-Allow-OriginTkTrailerTransfer-EncodingUpgrade-Insecure-RequestsUser-AgentVaryViaWWW-AuthenticateWant-Digest [我来译!]WarningX-Content-Type-OptionsX-DNS-Prefetch-ControlX-Forwarded-ForX-Forwarded-HostX-Forwarded-ProtoX-Frame-OptionsX-XSS-Protection100 Continue101 Switching Protocol103 Early Hints200 OK201 Created202 Accepted203 Non-Authoritative Information204 No Content205 Reset Content206 Partial Content300 Multiple Choices301 Moved Permanently302 Found303 See Other304 Not Modified307 Temporary Redirect308 Permanent Redirect400 Bad Request401 Unauthorized402 Payment Required403 Forbidden404 Not Found405 Method Not Allowed406 Not Acceptable407 Proxy Authentication Required408 Request Timeout409 Conflict410 Gone411 Length Required412 Precondition Failed413 Payload Too Large414 URI Too Long415 Unsupported Media Type416 Range Not Satisfiable417 Expectation Failed418 I'm a teapot422 Unprocessable Entity425 Too Early426 Upgrade Required428 Precondition Required429 Too Many Requests431 Request Header Fields Too Large451 Unavailable For Legal Reasons500 Internal Server Error501 Not Implemented502 Bad Gateway503 Service Unavailable504 Gateway Timeout505 HTTP Version Not Supported506 Variant Also Negotiates507 Insufficient Storage508 Loop Detected510 Not Extended511 Network Authentication RequiredCSP: base-uriCSP: block-all-mixed-contentCSP: child-srcCSP: connect-srcCSP: default-srcCSP: font-srcCSP: form-actionCSP: frame-ancestorsCSP: frame-src [我来译!]CSP: img-src [我来译!]CSP: manifest-src [我来译!]CSP: media-src [我来译!]CSP: navigate-to [我来译!]CSP: object-src [我来译!]CSP: plugin-types [我来译!]CSP: prefetch-src [我来译!]CSP: referrer [我来译!]report-toCSP: report-uri [我来译!]CSP: require-sri-forCSP: sandboxCSP: script-src [我来译!]CSP: script-src-attr [我来译!]CSP: script-src-elem [我来译!]CSP: style-src [我来译!]CSP: style-src-attr [我来译!]CSP: style-src-elem [我来译!]CSP: trusted-types [我来译!]CSP: upgrade-insecure-requestsCSP: worker-src登录以获得 MDN 账户的好处。若您尚未创建账户，将在登录后看到该操作提示。