> Hi people, just a follow up to my earlier post.
>
> What is the best connection method (set of components?) using TCP\IP (or
> not??)
No need to step outside of the IP family, and as _everyone_ uses it these
days (that arn't running on a default 95 install)
> That can do the following.
>
> 1. send text in both directions.
TCP works, UDP would also work. I think its synchronous tho - only one way
at a time, tho I'm not sure why I think that :)
> 2. send streams in both directions.
UDP would be the best idea, I think. Depends if:
a) the packets need to come in inorder. (yes = tcp, no = udp)
b) the packets MUST GET THERE or its all over(yes=tcp, no = udp)
c) a massive level of performance is needed (yes = udp, no = tcp)
d) broadcast is needed (yes = UDP or TCP multicast(ouch), no = either one)
TCP/IP is reliable, point to point, connection-oriented protocol. You bring
up a connection, send data, receive data (etc), and disconnect. the server
then goes back to listening (well, it kinda was before). It is generally
synchronous (tho windows allows you to use call-backs).
UDP/IP is not reliable, is broadcast or point-to-point, and its
data-gram/packet oriented. You get the IP and port of the remote machine and
send a packet. Thats it. No reponse packet, no nothing. You can also send it
to a broadcast address for the entire subnet. Its usually async in nature
(send and forget). EXCELLENT for streaming servers like real-audio (where
you get clicks for missed packets). it doesn't traverse filewalls well tho.
I did an remote telemetry thing at uni, between an SGI (nice :) ) and a PC.
It had a TCP control 'socket' (give me this, stop, start etc), and UDP for
the telemetry data - if I missed a packet, the world was not over.
ObAside, the SGI had a 100meg network card in it, and I used it from home.
It flooded my modem, so I couldn't kill it, and the pipe from Tamaki to
AKUni was so "small" (2meg) that I bought that down too. good job it was
about 2am :) I couldn't do that with TCP,only UDP.
> 3. Maintain a connection and know when disconnected.
TCP. Period.
> Nic, your a bit of a wizz at this sort of stuff as I recall,
Not really - my flatmate, Damon, is/was rather a god at it - he wrote a nice
sockets library, head and shoulders above the likes of DWinsock. I know a
lot of the theory, not a lot of the practice.
N
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