[standards-jig] VoIP, JEP-0065 and UDP?
m at tthias.net
Sun Jan 25 15:58:50 UTC 2004
Krzysztof Szyntar schrieb am 2004-01-25 16:55:21:
> If I understand correctly, you say that it's imposible to get an answer to
> your UDP packets if you are connected through a NAT?
No that is not what I said.
> That's not quite true. Most NATs, after someone sends a UDP datagram,
> leave the port it went through open (for a minute or so) and listen
> for some result.
Right. But you do not need an external proxy for this. Two clients both
behind NAT can open their NAT each other without the need for a third
> That's why services such as ping are possible.
ping does not use UDP. Ping uses ICMP.
> So if we take advantage of this behaviour, we can definitely construct
> a UDP proxy.
Why a proxy if it is possible with the same technique without it?
More information about the Standards