Multicast output

[AnWaKZ]

'm trying to receive an SRT stream and send a UDP multicast through a specific network interface without an IGMP request. I've checked it works locally, but not from another computer. What could be the problem?

srt-live-transmit "srt://192.168.1.10:9999" "udp://239.1.1.10:10000?adapter=192.168.10.10" -a -s -f

[AnWaKZ]

Wireshark shows the source = 192.168.10.10 and destination = 192.168.10.10 to be the same

[ethouris]

Did you set also the source?

See the documentation for details.

Also note that a problem might be platform-specific. On Windows there are different rules for setting things for multicast, although the app should handle it.

[AnWaKZ]

For multicast the scheme is:

udp://GROUPADDR:PORT?parameters...
The HOST part (here: GROUPADDR) is mandatory always and designates the target multicast group. The @ character is handled in this case, but it's not necessary, as the IGMP addresses are recognized by their mask.
For sending to a multicast group:

The iptos parameter designates the Type-Of-Service (TOS) field for outgoing packets via IP_TOS socket option.

The ttl parameter will set time-to-live value for outgoing packets via IP_MULTICAST_TTL socket options.

The adapter parameter can be used to specify the adapter to be set through IP_MULTICAST_IF option to override the default device used for sending