4 ms·
There are no such thing as "UDP connections". UDP is datagram based : you send a packet to an address, either it reaches its destination either it not (regardle
by paraboul 13y ago
There are no such thing as "UDP connections". UDP is datagram based : you send a packet to an address, either it reaches its destination either it not (regardless of the order). A packet can be dropped in case of network congestion, TTL that reaches 0, etc.
That is : One can easily rewrite a TCP-like on top of UDP.
- pjc50 13y agoAlmost every real use of UDP is "pseudo connection based", and lots of NAT systems operate on that basis: that a packet going (host,port) -> (host2,port2) implies both that there might be packets in the reverse direction and further packets between that pair of ports. This isn't baked into the protocol, but in practice everyone relies on it.
- jws 13y agoNAT mapppings will time out.
- BatFastard 13y agoWhile a UDP datagram not a "connection" in the TCP sense. You often send a packet via UDP from a port on one machine, to a different port on the same or different machine. If one of those ports changes, then it effectively "breaks" the connection. Since you are no longer getting data on the port you expect to receive it from. So while a pair of UDP ports are not a "connection", it is often a useful abstraction to treat them as one.
- the_mitsuhiko 13y agoA firewall treats continuous messages exchange between two endpoints as a connection. This is also what NAT punching takes advantage of.
- hawleyal 13y agoYou are objecting to semantics, not substance.