New UDP commands example

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Re: New UDP commands example

By cicciocb
- Tue Apr 05, 2016 10:12 am #44874 Unfortunately I don't think will be so easy.
It seems that this should require a combination of mDNS and mDNS responder.
Maybe I'm wrong but the DNS is just a way to associate names to IPs; at the end you still require the list of the names!
This will oblige to set a specific name into each ESP, but the DNS server will not be able to recognise the ESPs from the other devices on the network (PC, tablet, ..).

I think that probably the broadcast / multicast technique is more adapted with this need.
One simple idea could be to dedicate a pin for the identification, running a specific code at startup only if this pin is 1, for example.
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Re: New UDP commands example

By Electroguard
- Tue Apr 05, 2016 4:07 pm #44918 I was thinking of something fairly simple just using the arbitrarily assigned names rather than network names.

Assume all nodes started out with identical network names of "DEFAULT", all with the ability to flash out their DHCP IP address at bootup on the blue LED, and all with the ability to broadcast a UDP "Who's There?" using the flashing button (which acts just like any normal GPIO after bootup).

Each time you add a new node, you connect to it's flashed address and rename it to whatever it needs to be for its intended role.

For transmitter nodes like PIR sensors etc, there may already be some called PIR1, PIR2, PIR3 etc, so better to use the local "Who's There?" button to get all existing nodes to respond with their names, then an appropriate name can be assigned without risk of adding any duplicates.
Similarly for receiver nodes, in which case the newly assigned name obviously needs to match the name that will be used by any relevent tranmitter nodes to address it by.

The important points are that our network configuration can initially be a standard default for all, and nodes can subsequently be called something relevent to our system rather than have anything network-related imposed on them.


By the way cicciocb, any chance you could you do a stripped down version of your udp util which is name-oriented rather than IP oriented please?

It needs to issue a "Who's There?" broadcast and list the responders names and associated IP addresses of course, but it would be handy to have a textbox for sending name-based broadcast requests to anything, rather than just those names returned from a "Who's There?" query.

To try to explain things better, if I wanted a voice announcer node in the lounge, and another one in the office, I might name one MP3lounge and the other MP3office. This would allow them to be addressed uniquely by full name when required, or alternatively by group, just using the initial common part of the name. So it would be useful for the util to be able to send test messages to partial names like MP3 which wouldn't show up in the list of available returned names from any "Who's there" request.
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