Hi Andy,
Some panasonic TV’s send data to a multicast group. I assume it is part of the Discovery function for the Android and iOS apps. When the TV is turned on, it immediately sends out a multicast to port 1900 as below.
Ethernet II, Src: WistronN_f1:65:5a (60:02:b4:f1:65:5a), Dst: IPv4mcast_7f:ff:fa (01:00:5e:7f:ff:fa)
Internet Protocol Version 4, Src: 192.168.Y.XX, Dst: 239.255.255.250
0100 … = Version: 4
… 0101 = Header Length: 20 bytes
Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT)
Total Length: 368
Identification: 0x9c00 (39936)
Flags: 0x00
Fragment offset: 0
Time to live: 4
Protocol: UDP (17)
Header checksum: 0x66c1 [validation disabled]
Source: 192.168.Y.XX
Destination: 239.255.255.250
[Source GeoIP: Unknown]
[Destination GeoIP: Unknown]
User Datagram Protocol, Src Port: 13719 (13719), Dst Port: 1900 (1900)
Source Port: 13719
Destination Port: 1900
Length: 348
Checksum: 0x9f73 [validation disabled]
[Stream index: 529]
Hypertext Transfer Protocol
NOTIFY * HTTP/1.1\r\n
HOST: 239.255.255.250:1900\r\n
CACHE-CONTROL: max-age=1800\r\n
LOCATION: http://192.168.Y.XX:55000/dmr/ddd.xml\r\n
NT: urn:schemas-upnp-org:service:AVTransport:1\r\n
NTS: ssdp:alive\r\n
SERVER: FreeBSD/8.0 UPnP/1.0 Panasonic-MIL-DLNA-SV/1.0\r\n
USN: uuid:4D454930-0100-1000-8001-20C6EBEC2E6A:
schemas-upnp-org:service:AVTransport:1\r\n
\r\n
[Full request URI: http://239.255.255.250:1900*]
If the binding matched the source address and multicast to port 1900 then it could provide status. Not sure how to do this, may be there is a feature request for the binding.
dkw