When I open my application after a while, I received log:
440: CFNetwork internal error (0xc01a:/BuildRoot/Library/Caches/com.apple.xbs/Sources/CFNetwork/CFNetwork-758.4.3/Loading/URLConnectionLoader.cpp:289)
I solved my situation, it is not AFNetwork's issue, I use a invalid SSL certification and SDWebImage, when use the option 'SDWebImageAllowInvalidSSLCertificates' in SDWebImage and get a http image (not https image), you will get this error. the protocol (http or https) not being recognized automaticly by SDWebImage.
my solution: I not change SDWebImage’s code, I just write a wrapper for recognized protocol (http or https). I use '0' option for http images and 'SDWebImageAllowInvalidSSLCertificates' option for https images (my https certification is self signed or invalid). If yours cer is valid , I think SDWebImage works well.