[boost] How to resolve connection via route in proxy server?

Hi, I can use boost to query and to resolve TCP connection from a remote server which has a public IP address: boost::asio::ip::tcp::resolver::query query(host, port); resolver.async_resolve(query, boost::bind(&ConnectionClient::handleResolve, this, boost::asio::placeholders::error, boost::asio::placeholders::iterator)); But how can I connect to the remote server which does not have a public IP address, I have to connect it via route from a proxy server public IP address? Thank you. Kind regards.