Merge pull request #124213 from RussellR-MSFT/patch-4

ANPTA: Update front-door-http-headers-protocol.md

Author: Court72

articles/frontdoor/front-door-http-headers-protocol.md

@@ -35,7 +35,7 @@ Azure Front Door includes headers for an incoming request unless they're removed
 | X-Azure-SocketIP |  `X-Azure-SocketIP: 127.0.0.1` </br> Represents the socket IP address associated with the TCP connection that the current request originated from. A request's client IP address might not be equal to its socket IP address because the client IP can be arbitrarily overwritten by a user.|
 | X-Azure-Ref | `X-Azure-Ref: 0zxV+XAAAAABKMMOjBv2NT4TY6SQVjC0zV1NURURHRTA2MTkANDM3YzgyY2QtMzYwYS00YTU0LTk0YzMtNWZmNzA3NjQ3Nzgz` </br> A unique reference string that identifies a request served by Azure Front Door. This string is used to search access logs and critical for troubleshooting.|
 | X-Azure-RequestChain | `X-Azure-RequestChain: hops=1` </br> A header that Front Door uses to detect request loops, and users shouldn't take a dependency on it. |
-| X-Azure-FDID | `X-Azure-FDID: 55ce4ed1-4b06-4bf1-b40e-4638452104da` <br/> A reference string that identifies the request came from a specific Front Door resource. The value can be seen in the Azure portal or retrieved using the management API. You can use this header in combination with IP ACLs to lock down your endpoint to only accept requests from a specific Front Door resource. See the FAQ for [more detail](front-door-faq.yml#what-are-the-steps-to-restrict-the-access-to-my-backend-to-only-azure-front-door-) |
+| X-Azure-FDID | `X-Azure-FDID: a0a0a0a0-bbbb-cccc-dddd-e1e1e1e1e1e1` <br/> A reference string that identifies the request came from a specific Front Door resource. The value can be seen in the Azure portal or retrieved using the management API. You can use this header in combination with IP ACLs to lock down your endpoint to only accept requests from a specific Front Door resource. See the FAQ for [more detail](front-door-faq.yml#what-are-the-steps-to-restrict-the-access-to-my-backend-to-only-azure-front-door-) |
 | X-Forwarded-For | `X-Forwarded-For: 127.0.0.1` </br> The X-Forwarded-For (XFF) HTTP header field often identifies the originating IP address of a client connecting to a web server through an HTTP proxy or load balancer. If there's an existing XFF header, then Front Door appends the client socket IP to it or adds the XFF header with the client socket IP. |
 | X-Forwarded-Host | `X-Forwarded-Host: contoso.azurefd.net` </br> The X-Forwarded-Host HTTP header field is a common method used to identify the original host requested by the client in the Host HTTP request header. This is because the host name from Azure Front Door might differ for the backend server handling the request. Any previous value is overridden by Azure Front Door. |
 | X-Forwarded-Proto | `X-Forwarded-Proto: http` </br> The `X-Forwarded-Proto` HTTP header field is often used to identify the originating protocol of an HTTP request. Front Door based on configuration might communicate with the backend by using HTTPS. This is true even if the request to the reverse proxy is HTTP. Any previous value will be overridden by Front Door. |