When sending UDP broadcast messages on the photon, the messages are received ok on other photons, but they are not received by the sender. This behaviour is different from the “old” firmware on the core and AFAIK not compliant with the specification for broadcast messages.
I am flashing locally, currently on the “latest” branch at tag “v0.4.4.rc.6”.
Any insights?
To receive multicast UDP messages, the firmware must be instructed to join a multicast group. This is being worked on and scheduled for the next (0.4.5) release.
Afaik, this is within spec and is how kernels typically implement multicast.
Aren’t broadcast and multicast two different things?
Good to know that multicast will be fixed, and most likely I will switch to this once it is released as it is probably more efficient for my use-case. (are your referring to this post?)
However, in case one would choose to use broadcast (e.g. sending to 192.168.0.255) instead of multicast, I believe the sender should always receive its own packet, which currently is not happening, but was working on the Core. (Probably one of few things working correctly with UDP on the core ;))
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Hi @mdma
[I see @nicodegunst answered while I was typing! I have to get faster!]
Broadcast and multicast are different things. When a host joins a multicast group, it sends an IGMP message to the router to say “Please route this group to me, I’m listening now.” I think that is what the WICED join command does (in addition to allowing the received packet through). Broadcast packets are not generally routed beyond the local subnet and no IGMP message is sent.
I think there must be another way in WICED to listen for broadcast messages.
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You’re right guys, I mis-read the OP - been awake for a long time and have the multicast fix in my mind! Ignore that post…in fact I’m surprised you can read it through all the brainfog! 
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Multicast would definitely be awesome, keep up the good work!