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Re: [colorforth] Re-connecting

John Drake wrote:


And yet MANY lists of "common ports" show POP3

running BOTH on TCP AND UDP.  Good grief, people
act like I'm making this up.  Anyway, I see no
reason for assinine comments like "are you smoking
something" or "you're being silly" or whatever.
Maybe they're all derived from the same list. Maybe it's just a standard way of setting them up. Maybe POP2 had a UDP implementation once and the POP3 list was derived from there...
Set against that, you have the RFC, the very nature of a POP3 connection (which last time I used telnet to port 110, assumed a constant connection between the two machines, the dropping of which would signal the end of the connection), and a noticeable paucity of POP3 servers that advertise UDP support.
You're taking one source that says what you want to hear and saying that all the sources that contradict it are wrong. Well, you're welcome to do that, but it's verging on the solipsistic. Alternatively you could consider that perhaps the common ports list is the least authoritative source that's been brought up so far... since its only function is to give numeric ports human-readable names. 


Yeah, I'm aware of the advantages of TCP over UDP.

I'm aware that TCP is connection oriented and UDP
is "connectionless".  And yeah, I wouldn't want
to not get my email.  Yet UDP is used for TFTP.
Wouldn't it be bad not to get the last few bytes
of a 10 MB file coming down over a 56K connection?
It would, but since TFTP (_trivial_ file transfer protocol) is designed purely for booting servers with and is hopelessly insecure, anyone seriously doing such a thing should be shot... and of course, if you don't get the last K of your kernel from the LAN, it's a lot more solvable - you just reboot. There was a real file transfer protocol that used UDP; it was called FSP - but I don't have happy memories of using it. FTP (which is robust, stable, complex, and can be made secure) uses TCP. 


This is the bottom line.  For WHATEVER reason
some POP3 servers are listening on UDP.
Please provide an IP address of one... or at least a reference to some code we can actually run for ourselves that supports that assertion. At the moment, all I can see that you have to go on is one line of one widely-dispersed file, which I dare say not even its authors would claim was authoritative, and I think it's worthwhile pointing out that if you're expecting to be able to talk to your ISP's POP3 server using UDP then you're highly likely to be disappointed... 


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