Sony SNC-DF70P User Manual page 22

a router which does not correspond to the multicast
or the fire-wall is installed between the camera and
the computer, the video/audio may not played
properly. In this case, select TCP or UDP
(Unicast).
4
Click OK to close the dialog.
If you do not change the transmission setting, click
Cancel.
22
Switching TCP/UDP Transmission Mode