Connection Header with NSURLRequest

Hi,

While I'm developing an application, I constantly getting Error Domain=NSURLErrorDomain Code=-1005 "The network connection was lost." which is not expected and happens intermittently.

While I was looking into some solutions on the web, there are few scenarios that could potentially cause this issue.

Eliminating all other possibilities, I've been left with only one possiblity which is "Connection: Keep-Alive" header in the response.

One note is, I do not have an access to the server to change the behvaiour.

Funny thing is that according to the RFC standard, if the client request with "Connection: close" in the request header, the response should return "Connection: close" respectively.

However, I've observed in iOS SDK, even with "Connection: close" header in the request, this connection header in the request keeps being ignored and the server returns a response with "Connection: Keep-Alive" header. I've also double checked with Android SDK, and other REST client by sending the same request to the same server with "Connection: close" header in the request, all other clients are getting response with respective response header "Connection: close".

I understand that this "The network connection was lost." error may not really be related to iOS SDK if the server respects RFC standard; however, as I do not have an access to the server environment, I am trying to resolve this issue on the client side.

Is this a bug on iOS SDK that "Connection" header in the request is not being respected in the response? or am I doing something wrong or missing something?

For a note, I've tested with iOS 9.1 to iOS 11 on Xcode 9.3.1, and all scenario provides the same result.

And I'm using NSURLSession along with NSURLSessionDataTask to make the request.

Please advise.

Thanks,