HTTP Status Code 417 – Expectation Failed

One or more conditions given in the request header fields evaluated to false when tested on the server. This response code allows the client to place preconditions on the current resource state (its current representations and metadata) and, thus, prevent the request method from being applied if the target resource is in an unexpected state.

The server cannot or will not process the request due to something that is perceived to be a client error (e.g., malformed request syntax, invalid request message framing, or deceptive request routing).

The server understands and is willing to comply with the client’s request, via the Upgrade header field, for a change in the application protocol being used on this connection. The server MUST generate an Upgrade header field in the response that indicates which protocol(s) will be switched to immediately after the empty line that terminates…

Risk deterrence is the process of implementing deterrents to would-be violators of security and policy. Example: Implementing warning banners on your system login pages that only authorized personnel can access those systems.

The concept of threat modeling is where potential threats are identified, categorized, and analyzed. There are two different ways threat modeling can be performed: proactive and reactive. Proactive threat modeling: performed during the design and development phase. Reactive threat modeling: performed after a product has been created and deployed. Once potential threats are discovered, the…

The method could not be performed on the resource because the server is unable to store the representation needed to successfully complete the request. This condition is considered to be temporary. If the request that received this status code was the result of a user action, the request MUST NOT be repeated until it is…