Increase Concurrent Downloads in IE

The HTTP spec specifies that you can not have more than 2 transfers when using HTTP 1.1, or more than 4 transfers in HTTP 1.0.

So what this means is that you can’t download a bunch of files from the same server at the same time.

More info on this problem can be found at http://support.microsoft.com/kb/183110.

You can configure WinInet to exceed this limit by creating and setting the following registry entries:

Note By changing these settings, you cause WinInet to go against the HTTP protocol specification recommendation. You should only do this if absolutely necessary and then you should avoid doing standard Web browsing while these settings are in effect:

HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionInternet Settings

MaxConnectionsPerServer REG_DWORD (Default 2)
Sets the number of simultaneous requests to a single HTTP 1.1 Server

MaxConnectionsPer1_0Server REG_DWORD (Default 4)
Sets the number of simultaneous requests to a single HTTP 1.0 Server

These settings are made for a particular user and will have no affect on other users who log on to the computer.

In Internet Explorer 5, it is possible to change the connection limit programmatically by calling the InternetSetOption function on NULL handle with the following flags (note that it will change connection limit for the whole process):

INTERNET_OPTION_MAX_CONNS_PER_SERVER INTERNET_OPTION_MAX_CONNS_PER_1_0_SERVER

Note If the process has established a connection to a server, if you change the connection limit by calling InternetSetOption, the function does not have any effect to subsequent connections on the same server. This occurs even if a previous connection is disconnected prior to the call to InternetSetOption. Connection limit does affect all other servers.

Keywords: IE Downloads, Concurrent Downloads, 2 downloads

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s