by Darius Kazemi, Jan 22 2019
RFC-22 is an update to RFC-11. It is authored by Vint Cerf and dated October 17, 1969. Twelve days before the first message will be sent over the ARPANET!
There is a new control message format that's been defined by UCLA. It does not conform to ASCII, as it's a control message and not plain text. Hooray.
There are now 9 control messages that can be sent over a control link (link 0 or 1, depending on the nature of the message, I think):
- establish primary connection on link X
- establish auxiliary connection on link Y related to link X (if you'll recall, this means that link X sends commands and link Y sends files and data and things)
- acknowledge that we got your primary connection establishment message and are complying
- acknowledge that we got your auxiliary connection establishment message and are complying
- acknowledge that we got your primary connection establishment message and are NOT complying
- acknowledge that we got your auxiliary connection establishment message and are NOT complying
- message that says “please stop spamming link N, you are ruining things for everyone”
- message warning you that we are about to close a link
- message that says “ok you can go back to spamming link N”
Then the specific packing of bits (the header format) is laid out.
In RFC-11, text commands (presumably in ASCII) like “OPENAUX” were supposed to be sent to say things like “open an auxiliary connection”. Now we just send some packed data with a special numerical code. This means we send far less data over the network in order to do basic things like establish connections. This new encoding is like an order of magnitude more efficient in terms of the number of bytes being sent around.