Example methods are provided for a first endpoint to perform congestion control during communication with a second endpoint over a public network, the second endpoint being in a private network. The method may comprise generating a plurality of tunnel segments containing unreliable transport protocol data destined for the second endpoint and determining whether congestion control is required based on a data amount of the plurality of tunnel segments and a congestion window associated with a tunnel connecting the first endpoint with the private network. The method may further comprise, in response to determination that congestion control is required, performing congestion control by dropping at least some of the plurality of tunnel segments otherwise, sending the plurality of tunnel segments through the tunnel supported by the reliable transport protocol connection. [Fig. 3]