A little bump in the wire that makes the Internet faster

Fair queuing seems to have been an idea that was used for a while and then forgotten. It's been an obscure option on Cisco medium-speed routers for years, but only on by default for 2mb/s links and below.[1] Most of the attention on congestion control went into the TCP side, not the router side. There was too much attention to packet dropping, rather than packet reordering. In a router, you can do three things about congestion - drop, reorder, and delay. For decades, most of the action revolved around dropping, with Random Early Drop being popular. Reordering means you get to make decisions about what to reorder. That leads to policy issues, traffic shaping, quality of service, administrative interfaces, tuning knobs, and customer service/help desk calls. Which is why QoS never went much of anywhere outside of some tightly managed networks.

A big contribution of the bufferbloat guy is that he promotes the original dumb fair queuing - each source IP/source port/destination IP/destination port is one flow, and you service each flow equally. Nice and simple. No tuning. If that was in the middle of the network, you'd worry about people getting more bandwidth by gaming port numbers or something. But what's the point of gaming your own personal DSL router? In practice, the things that need really good latency on home DSL uplinks are acks, voice over IP, and game user action traffic, all of which are low-bandwidth. So the simple approach is good enough.

Early routers had barely enough CPU time to copy the bytes, let alone do fair queuing. So it wasn't in early routers. It's also a bit complex for a FPGA, so it's not in the big ones which route in hardware. (Nor is it that helpful there, because backbone routers don't buffer much.) That's how we got here.

It's embarrassing that this is still necessary to talk about. There's no excuse for big DSL operators deploying millions of routers with giant dumb FIFO buffers. Come on, AT&T.

A fair queuing add-on box is a definitive win only if the next link has a fixed data rate. DSL yes, cable maybe, cellular probably not. Cable modems at DOCSIS 3.1 and above are supposed to have DOCSIS-PIE [2], which is supposed to fix this.

Now will someone please do a startup that builds a little box? As a hobbyist thing this goes nowhere. As a little box you buy at WalMart, it does.

Or, AT&T guys, get your act together and ship this as standard. Thank you.

[1] https://www.cisco.com/c/en/us/td/docs/ios/12_2/qos/configura... [2] https://tools.ietf.org/html/draft-ietf-aqm-docsis-pie-02

John Nagle

> The only catch is... what upload/download speeds should we give to cake? Okay, I cheated for that one. I just asked my dad what speed his DSL link goes in real life, and plugged those in.

So the critical problem remains unsolved. If the ISP ever increases their speed cap, it goes to waste; if they decrease the speed cap, the fix stops working. I use a similar solution, but I have to turn it off and retest a few times a year, because Comcast sometimes changes the speed without notifying me.

I think the blog really overdid it with the analogies.

He mentioned that over 20Mbps you really don’t notice better browsing speed. He’s right. I have gigabit internet - usually around 950Mbps up and down. Nothing takes advantage of it in the real world. The best real world throughout I’ve gotten is through my work VPN in the middle of the night or transferring something to AWS. Even then it’s only 100Mbps. BackBlaze tops out at around 70Mbps with multiple threads running.

Video streaming at its highest but rate is only 15Mbps.

Worked like a charm. I remember that it was specifically designed to get rid of buffer bloat, with traffic prioritization for streaming, VOIP, etc. I honestly think it was config-less though, so it doesn’t make sense unless it was also testing the speed on a regular basis and adjusting itself.

Edit: found it: Hawking Broadband Booster (HBB1) https://www.amazon.com/dp/B0009PLO0Q/ref=cm_sw_r_cp_api_jEiB...

I got my Eth port 1 to bridge to WAN but it's not doing any shaping - my port 4 to Wan standard dual-nat shaping is working, however.

I'm currently using an EdgeRouter Lite iii which reduces the download speed from gigabit to 130 Megabits per second when SQM is turned on.

However this is too much editorializing - I don't bother reading any more with this style of writing.

>Okay, new analogy: oil pipelines! Wait, those are unfashionable now too. Uh... beer taps... no, apparently beer is bad for diversity or something... chocolate fountains!

You installed rate limiter that drops packets and doesn't buffer.

You don't need to write it like you're writing ad copy "This one little secret".

Post the situation, the plan, and details/documentation.

I do not have the time to read a literal 6,000 words.