# File lib/fog/terremark/vcloud.rb, line 69
        def default_network_id
          if default_vdc_id
            @default_network_id ||= begin
              networks = get_vdc(default_vdc_id).body['AvailableNetworks']
              if networks.length == 1
                networks.first['href'].split('/').last.to_i
              else
                nil
              end
            end
          else
            nil
          end
        end