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<font size=3>At 03:11 PM 1/23/2006, Bob Braden wrote:<br>
<blockquote type=cite class=cite cite="">Joe,<br><br>
I think you are confusing ARPAnet NCP port assignments with TCP/IP<br>
port assignments.</blockquote><br>
it's worse than that.<br><br>
without prejudice to my views on the subject 'history''s accuracy, or
even comprehensibility, my first reaction to the message this one was
responding to was 'what? we didn't have ports when rfc 33 would
have been written; i'm not even sure we had sockets yet.'<br><br>
so i looked at what purports to be a transcription of rfc 33 according to
the first googhit on 'rfc index' and immediately noticed that it had a
1973 [sic: 3, as in three] publication date, which is absurd. [but
enough other 2-digit rfcs refer to it that i'll take the 3 as a typo for
0.] sure enough, we had sockets, not ports.<br><br>
the date typo red herring aside, a little skimming [and some
firefox-finding] made it clear that rfc 33's use of 'port' was
rhetorical, not technical. that is, it couches everything in terms
of sockets at the beginning, and uses the term a number of times, then
goes on to some meant-to-be useful abstractions about ports later in the
document, or perhaps was sneakily trying to get the name changed but that
definitely didn't take if it was the intent. 'sockets' was the term
of art for years. [it might be the case that 'port' appeared often
enough in the later part of the document, which was presumably led to by
a search on something like 'rfc ports', that 'socket' didn't get noticed
up at the top, i suppose.] it's also worth noting that rfc 33
predated the final form of the arpanet host-host protocol, although it
was apparently a fairly major step on the path to the ah-hp.<br><br>
i'm utterly disinclined to dig out the references, especially when i know
from personal experience that some references aren't available in the rfc
archives, but my memory's pretty clear on the following: the original
arpanet host-host protocol [often miscalled ncp, which was really the
term supposed to be used for the combination of the host-host and
host-imp protocol interpreters in given hosts] used pairs of simplex
sockets for processes to communicate over/through, and the underheralded
'initial connection protocol' used 'well-known sockets' to allow a user
process to get the number [probably the even number, but who cares] of
the base socket of the even-odd pair it would be able to use to 'talk' to
the desired server process [telnet = 3, ftp = 23 sounds faintly familiar
but is almost certainly wrong]. well-known sockets were the first
thousand or so. the rest of the socket world could be used freely
by pairs of processes for whatever purpose they 'wanted' [provided, of
course, they knew what numbers to use ... which was what the initial
connection protocol achieved for telnet, ftp, and some others i can't be
bothered to try to remember].<br><br>
the real point is that when tcp came along, duplex communication paths
seemed more sensible, and they were called ports [i suspect after
starting out being called sockets as well, but i wasn't going to the tcp
design meetings because i wasn't implementing a tcp interpreter, so can't
be sure]. the similarities to good old ah-hp socket pairs were
pretty striking, tho ... and, of course, telnet and ftp user processes
then went off to well-known ports instead of well-known sockets [but
since as well as being duplex ports also didn't have to be unique on both
ends the initial connection protocol became pretty much moot].<br><br>
to end on a charming anecnote, what's left of my memory's hazy [and i'm
too lazy to refresh it] on the exact 'shape' of socket
numbers/identifiers, but i do clearly recall -- and a quick look back at
rfc 33 confirms, even tho i'm pretty sure the 'shape' it specifies isn't
what eventually was settled on -- that they used to have a final 8-bit
field called 'aen', for 'another eight-bit number', and good old ed
[or edwin, as he prefers] meyer, who was my officemate at project mac at
the time, suggested that the field should be called 'pin' rather than
'aen', since pins and sockets went together. sadly, it doesn't seem
to've made it into the literature, and i'm not at all sure that he even
proposed it in public, but i'm pretty sure the source code for the
multics host-host protocol interpreter went along with the joke
[especially since he wrote the initial implementation of it, and his
group leader was -- and still is -- inordinately fond of puns].<br><br>
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<font size=3>cheers, map<br><br>
[whose shoulder problems caused him to break down some time ago and
create a 'signature' file to apologize for the lack of his formerly
customary e-volubility -- and who's been employing shiftless typing for a
long time now to spare his wristsnfingers, in case you didn't know ...
and who's further broken down and done
http://www.lafn.org/~ba213/mapstuff.html , rather grudgingly]<br>
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