problems about name for namespace and template parameters

Recently I read some code about websocketpp, and the following code is what I'm confused about:

#include <somefile.hpp>
template <typename config>
class endpoint : public config::socket_type {          //--------A--------//
    typedef typename config::concurrency_type concurrency_type;//-----B------//
    ....
}

In the somefile.hpp, there is namespace which also called config. So I don't know whether the name "config" in A and B denoted the that namespace or the template parameter. I guess it is template parameter.

Thx for all people asking my questions.