I opened https://github.com/quicwg/base-drafts/issues/5000 to track this (it's our only issue, but I see no reason not to save this).
On Tue, Apr 25, 2023, at 07:11, Ian Swett wrote: > You're correct that this sentence is in contrast to the first sentence > of the section: > "When a PTO timer expires, a sender MUST send at least one > ack-eliciting packet in the packet number space as a probe." > > The intent was 2, that when there is no unsent or unacknowledged data > available, a sender MAY mark all packets in flight as lost. As an > individual, I would not recommend this, but in the same way we allow > retransmitting packet contents in their entirety, we allow this. > > I agree this is slightly unclear and whenever we do 9002bis, it'd be > ideal to clarify this. > > Ian > > On Thu, Apr 20, 2023 at 3:13 AM Timo Völker <[email protected]> > wrote: >> Hi, >> >> I wonder what the word “Alternatively” refers to in RFC9002 Section 6.2.4. >> Sending Probe Packets. >> >> I would summarize the Section before the word as follows: >> >> "When a PTO timer expires, a sender MUST send at least one ack-eliciting >> packet [...] >> An endpoint SHOULD include new data in packets that are sent on PTO >> expiration. >> Previously sent data MAY be sent if no new data can be sent. [...] >> When there is no data to send, the sender SHOULD send a PING or other >> ack-eliciting frame in a single packet, rearming the PTO timer." >> >> Then, the sentence that confuses me: >> >> "Alternatively, instead of sending an ack-eliciting packet, the sender MAY >> mark any packets still in flight as lost." >> >> Alternatively to what? >> >> (1) Alternatively to send a probe packet at all. >> Or >> (2) Alternatively to send a probe packet in case the sender has no unsent or >> previously sent data available? >> >> Based on the history of the Section, my guess is (2). But, I can’t tell >> based on the current text. Since both options are in contrast to the first >> sentence of the Section, I might have missed something. >> >> Timo
