code: function closeOldestServer() {
          var oldest = null;
          Object.keys(self._peerServers).forEach(function (k) {
            if (oldest == null) {
              oldest = k;
            }
            else {
              if (self._peerServers[k].lastActive <
                self._peerServers[oldest].lastActive) {
                oldest = k;
              }
            }
          });
          if (oldest) {
            closeServer(self, self._peerServers[oldest], null, false);
          }
        }
docs: This is the server that will listen for connection coming from the application