is there limit on concurrent connection number when browser downloading html resources?

Generally, in order to speed up overwhole loading, browser would open ser开发者_开发知识库val concurrent connection to download the resource files parallelly.

I want to know, for a certain browser, is there a limit on the concurrent connection number?

Since you don't provide much detail only some general pointers:

The HTTP standard defines a connection limit per client<->server. In Windows for example there is a registry setting which can be used to change that... Not all browsers/browsers versions and/or OS/OS versions implement the standard-defined limit(s) and/or take the registry setting into account...

It's browser dependent.

For example, FireFox has a default of 30 global max, and 15 per server, which can be increased to 65535.

FAQs:_About:config_Entries">http://kb.mozillazine.org/Firefox_:FAQs:_About:config_Entries

And apparently Chrome's limits are lower (6) with no ability to configure.

Google for more information