[tcpm] 793bis: reset generation section

[Wesley Eddy <[e-mail]>]

Gorry had a few comments on the "Reset Generation" section of 793bis 
that I have some proposed responses for:


On 8/28/2019 11:39 AM, Gorry Fairhurst wrote:
> ---
> OLD:
>     As a general rule, reset (RST) must be sent whenever...
> - I can't fathom what was intended, isn't this a RFC2119 SHOULD?

I think there's more specific text elsewhere, so we probably shouldn't 
put 2119 language here.  Instead of "must be sent" we might just say "is 
sent".


> ---
> OLD:
>    SYNs addressed to a non-existent connection are
>    rejected by this means.
> - Is that a complicated way of saying an RST is sent, or is it 
> something else, please clarify,
> is the word "addressed" correct here? Could this be rewritten as a 
> "SYN segment that
> does not match an existing connection..."

I'm fine with this editorial change, if nobody objects.


> - This then leads me to ask why this does not refer to SYN cookies?

I'm not sure that's needed or directly relevant, because SYN cookies are 
for protecting actual listening sockets (not non-existent ones).


> ---
> OLD:
>       any unacceptable segment (out of window sequence number or
>       unacceptable acknowledgment number) must elicit only an empty
>       acknowledgment segment containing
> - what does "elicit" mean here and what is an empty ACK segment?

I think it's just editorial, but we could change:

"elicit only an empty acknowledgement segment"

to:

"be responded to with an empty acknowledgement segment (without any user 
data)"