What is the difference between these two registry settings involved in downloading more than 2 files at a time for IE8+

Question

I'm trying to determine what each of these affect. Adding a DWORD to both of these settings for iexplore.exe and setting the decimal value to 10 allows your to create more connections to servers when using IE, but Im curious why there are 2 entries...

What is the difference between:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\MAIN\FeatureControl\FEATURE_MAXCONNECTIONSPER1_0SERVER

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\MAIN\FeatureControl\FEATURE_MAXCONNECTIONSPERSERVER

Answer 1

The first one sets the connection limit that you want for HTTP 1.0 connections, and the second one is for HTTP 1.1 connections.

From Wikipedia:

HTTP/1.1 is a revision of the original HTTP (HTTP/1.0). In HTTP/1.0 a separate connection to the same server is made for every resource request. HTTP/1.1 can reuse a connection multiple times to download images, scripts, stylesheets et cetera after the page has been delivered. HTTP/1.1 communications therefore experience less latency as the establishment of TCP connections presents considerable overhead.