UDP Broadcast IP List

Ability to list specific IP Addresses to send UDP data to instead of the current UDP Broadcast to every device on the network.

Would allow to target that broadcast to only the devices that needs them.

is that even possible with UDP? I’m not an network expert, but I thought UDP is always broadcast to any node inside the subnet (network mask). It doesn’t carry an address of the receiving nodes. Of course you could send an address as part of the message, but then the node still needs to receive the message and decide it is for this node on not. Also the sender doesn’t know those addresses of the receivers. With TCP it is a totally different story.


Doh! Good point. Forgot UDP doesn’t include an IP, only a port.

I was just wondering really if there’s a way to get data from the hub to particular devices rather than everything on the network.

Sure you one could use tcp instead of udp. But then the data only goes to a single device. During that time the network is occupied so it doesn’t save time to use tcp over udp, it only saves processing power at the device that decide to listen to the udp traffic and decide not to use the data (I left out some details). Advantage of udp is that it can go to multiple devices at the same time, there is however no feedback on the network protocol to make sure the data arrives at the intended receivers.

TCP/UDP are layer 4 protocols, they don’t need to know about IP addressing because that occurs at layer 3 (IP). Yes, you can unicast UDP packets (ie route them).


Why ? Is there a problem the current implementation causes ?

I kinda like it, FWIW. I have multiple computers listening, one running weewx, one (container) running my UDP listener that feeds influxdb. Works great.