4 ms·
Looking in /etc/services, it seems that most early protocols used odd numbers on the server side (echo, finger, chargen, qotd, etc) I wonder if the standard wa
by isostatic 8y ago
Looking in /etc/services, it seems that most early protocols used odd numbers on the server side (echo, finger, chargen, qotd, etc)
I wonder if the standard was originally
Client -> Server -- send to an odd port
Server -> Client -- send to an even port
By the time RFCs reached 4 figures, that (if it did exist) had gone -- gopher was assigned to port 70 for example.
- js2 8y agoIt’s apparently due to hysterical raisins. The NCP host-host protocol was simplex and required a pair of sockets. The convention for the return socket was to connect to a “port” one less than the receiving port. At least I think. See the connection establishment process described starting on page 7 of https://tools.ietf.org/html/rfc33 https://tools.ietf.org/html/rfc33
- isostatic 8y agoThanks, something I hadn't encountered: "On January 1, 1983, known as flag day, NCP was officially rendered obsolete when the ARPANET changed its core networking protocols from NCP to the more flexible and powerful TCP/IP protocol suite, marking the start of the modern Internet." I was 13 months old then, and (After conversations at tonight's summer party) I'm apparently "old". Sigh. > hysterical raisins Took a while to realise you went for "historical reasons". But then see summer party (and tomorrow's P45)....