> On 26 Jan 2020, at 09:42, HilaireFernandes <hila...@drgeo.eu> wrote:
>
> Sven Van Caekenberghe wrote
>> Sounds nice, and indeed a (more) fun way to teach programming.
>>
>> But I still fail to see why you have to filter incoming UDP packets on
>> their origin address.
>
> If third party software on the workstation are connected to other network
> services, don't you want to filter out? Or am I missing something?
I think so: you listen on an UDP socket on a specific port (and optionally
bound to a specific network interface on your machine), then you get only
datagrams directed to you - this happens at the OS level.
A (at host:port) sends a datagram to B (at host:port), to reply, B looks at the
datagram to figure out the sender's info and replies.
You can study the example UDPSocketEchoTest to see how this works.
HTH,
Sven
