I feel like that’s an ungenerous characterization. First, QUIC should contain some minimal connection info unencrypted that can be middleware to do some basic traffic shaping. It’s also intentionally very careful to avoid showing too much to avoid “smart” middleware that permanently ossifies the standard as has happened to TCP.
Finally, traffic shaping on a single machine is pretty easy and most routers will prefer TCP traffic to UDP.
Finally, the correct response to overwhelm is to drop packets. This is true for TCP and UDP to trigger congestion control. Middleware has gotten way too clever by half and we have bufferbloat. To drop packets you don’t need knowledge of streams - just that you have a non-skewed distribution you apply to dropping the packets so that proportionally all traffic overwhelming you from a source gets equally likely to be dropped. This ironically improves performance and latency because well behaving protocols like TCP and QUIC will throttle back their connections and UDP protocols without throttling will just deal with elevated error rates.
So what? You dropping packets, and they are still coming, eating BW and buckets.
Because traditionally UDP did not have any flow control, you just treat is as kinda CBR traffic and so you just want to leave it queues as fast as it can.
If there was a lot of TCP traffic around, you just drop packets there and vioala, congestion kick sin and you have more room for importand UDP traffic.
Now, if you start to drop UDP packets your UX drops.. packet loss in FPS games is
terrible, even worse than a bit of jitter. Thank you.
But your complaint is about QUIC, not generic UDP. QUIC implements TCP-like flow control on top of UDP, designed to play well with TCP congestion control.
QUIC does play well with others. It's just implemented in the userspace QUIC library instead of the network stack.
I really don’t follow your complaint. QUIC (and other similar UDP protocols like uTP used for BitTorrent) implement congestion control. If packets get dropped, the sender starts backing off which makes you a “fair” player on the public internet.
As for gaming, that remains an unsolved problem, but QUIC being UDP based isn’t any different than TCP. It’s not like middleware boxes are trying to detect specific UDP applications and data flows to prioritize protecting gaming traffic from drops, which I think is what you’re asking for.
Finally, traffic shaping on a single machine is pretty easy and most routers will prefer TCP traffic to UDP.
Finally, the correct response to overwhelm is to drop packets. This is true for TCP and UDP to trigger congestion control. Middleware has gotten way too clever by half and we have bufferbloat. To drop packets you don’t need knowledge of streams - just that you have a non-skewed distribution you apply to dropping the packets so that proportionally all traffic overwhelming you from a source gets equally likely to be dropped. This ironically improves performance and latency because well behaving protocols like TCP and QUIC will throttle back their connections and UDP protocols without throttling will just deal with elevated error rates.