USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB • Hacker News Board

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#171

Post by cletus » Tue, Mar 05, 2019, 12:09 AM UTC

izacus wrote: post #86

sp332 wrote: post #3

Ars Technica just wrote an article about the confusing names of USB versions https://arstechnica.com/gadgets/2019/02/usb-3-2-is-going-to-... and now they have another one about this name. https://arstechnica.com/gadgets/2019/03/thunderbolt-3-become...

I feel like hand-wringing around that is a bit overexaggerated - at the end of the day the differences really matter for only really tiny subset of devices that need those 10GBit+ transfers and in that case you can guide yourself by the "SuperSpeed 10Gbit" "Superspeed 20Gbit" logos on the actual box. For everything else the protocols are forward and backward compatible, so you just plug in the cable and it works.

This issue is neither new nor irrelevant.

When USB 2.0 was introduced, it was a huge increase in speed. USB 1.1 is 11 Mbps whereas 2.0 is 480 MBps (theoretical). When this happened some camera manufacturers (Nikon I believe was one of them?) were identified as changing the marketing on their cameras to "USB 2.0". What this actually meant though was "USB 2.0 Full Speed", which is USB 1.1 speeds. USB 2.0 Hi-speed is 480.

Consumers don't need this or want it. Manufacturers just don't want to say "USB ".

You see the same thing with AT&T deciding its LTE iPhones are 5G because they want their network to sound more impressive than it is.

It's also why the strength bars on your phone show the strongest signal (2G/3G/4G) that your phone is getting, not the one its actually using.

The truth matters. False advertising matters. Markets only work with a minimum level of trust. All of this legerdemain erodes that trust.

I'm Australian and this is one place where I think the ACCC (equivalent to the FTC/FCC rolled into one) has way more teeth than their US equivalents. The ACCC, for example, ended ISPs advertising "unlimited" ISP plans that weren't truly unlimited (which was basically all of them). This also covered ISPs with hard or soft data caps where throttling would come into play. The ACCC also took ISPs to task on the truth in advertised speeds for services (which matters are lot for xDSL).

A more sensible standard would've been something like:

USB

eg USB 3.1C, USB 3.0A.

Or put the letter first.

But this whole USB 3.2 Gen 1 = USB 3.1 Gen 2 or whatever is just pure nonsense.

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#172

Post by microcolonel » Tue, Mar 05, 2019, 12:09 AM UTC

WhitneyLand wrote: post #124

What's optional? That's the most important thing to know is what's optional in the spec. That could make it great or a major pain. I'm referring to how many features the specification defines as "optional" for manufactures and that the USB organization requires for logos. This is why even USB-C is a nightmare. Consider a USB-C cable or device port. It could be charge only, data only, monitor support. There are even m…

I think there needs to be some brand for the full-fat port with everything connected to a certain standard.

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#173

Post by bits » Tue, Mar 05, 2019, 12:54 AM UTC

Whoa. Does the addition of Thunderbolt imply that all USB4 host systems are exposed to DMA attacks[0]?

Doesn't this open up every USB system (all systems?) to arbitrary, uncontrolled memory access including silently flashing new firmware/microcode to system components?

0: https://en.wikipedia.org/wiki/DMA_attack

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#174

Post by rjeli » Tue, Mar 05, 2019, 1:00 AM UTC

gumby wrote: post #78

781 wrote: post #22

Earlier quoted context omitted.

PCI Express is already working at those data rates.

Thunderbolt is PCIe.

Not quite: https://twitter.com/whitequark/status/1097777102563074048

"Thunderbolt, uh, does not expose PCIe lanes directly. Thunderbolt is an MPLS-like packet switching network that can encapsulate PCIe TLPs over a PHY and MAC without a spec, chips without documentation, and software with barely any support."

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#175

Post by dcbadacd » Tue, Mar 05, 2019, 1:08 AM UTC

cesarb wrote: post #157

elagost wrote: post #144

Earlier quoted context omitted.

I very much agree with you. I've deliberately avoided USB-C for this very reason. It's not that hard - I don't buy new gear very often, and I'm still using an old 5th-gen iPod every day - but there will be a day when I don't have much of a choice anymore. Bluetooth headphones, external hard drives, game controllers, media players, phones... The worst part about USB-C is that it can be implemented so wrong it bricks y…

> The worst part about USB-C is that it can be implemented so wrong it bricks your device! The miswiring that bricked his device, swapping GND and VBUS, could also happen with older USB plugs. There's nothing specific to USB-C about it, USB plugs have a defined polarity for the power pins since the very first version of the standard.

There's also the Nintendo Switch issue

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#176

Post by inetknght » Tue, Mar 05, 2019, 1:12 AM UTC

nickysielicki wrote: post #168

Retric wrote: post #162

Earlier quoted context omitted.

USB-C can send significantly more power, which makes it harder to protect devices in these cases.

It only happens after negotiation, so the higher potential wattage plays no role here. You'd need both a bad cable and an out-of-spec wall wart.

Do you think that combination of circumstances is rare enough that we shouldn't wonder about it?

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#177

Post by userbinator » Tue, Mar 05, 2019, 1:13 AM UTC

WhitneyLand wrote: post #124

What's optional? That's the most important thing to know is what's optional in the spec. That could make it great or a major pain. I'm referring to how many features the specification defines as "optional" for manufactures and that the USB organization requires for logos. This is why even USB-C is a nightmare. Consider a USB-C cable or device port. It could be charge only, data only, monitor support. There are even m…

The only way you can make a specification like USB "universal" is for parts of it to be optional. No one is going to build a USB mouse with a 40Gbit link speed, for example.

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#178

Post by dcbadacd » Tue, Mar 05, 2019, 1:15 AM UTC

StreamBright wrote: post #97

p1esk wrote: post #84

Earlier quoted context omitted.

Is it fast enough for 4K120 or 8k displays?

Do we need 8K displays at all? https://www.youtube.com/watch?v=ehvz3iN8pp4 https://www.youtube.com/watch?v=VxNBiAV4UnM

That's approaching the visual acuity of humans. I think 8K is going to be what we're going to end up with everything.

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#179

Post by [deleted] » Tue, Mar 05, 2019, 1:16 AM UTC

derefr wrote: post #114

gambiting wrote: post #100

Earlier quoted context omitted.

So remind me, why can you walk into any apple store, pick up a new MacBook and a 5K LG monitor, and when you plug in the monitor using the USB-C cable that was bundled with the MacBook it just won't work at all? My point is - the standards might be back and forward compatible. But the cables and ports definitely aren't - and your average consumer has absolutely no way of knowing. They look absolutely identical on the…

No wiring issues necessary; the MacBook just isn't powerful enough to drive a 5K display. (I think the question you meant to ask is why the MacBook can't drive an external 4K Thunderbolt display using its included cable, which is more interesting—IIRC, it can do so through an HDMI adapter plugged into the USB-C port, but it cannot do so over a USB-C cable. This still isn't about the cable, though; you can take the Ma…

[deleted]

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#180

Post by holy_city » Tue, Mar 05, 2019, 1:25 AM UTC

jsgo wrote: post #14

penagwin wrote: post #8

Here's an idea, let's make different connector shapes depending on the cable/connector's capabilities, lets do one for connectors that support display, one for power, one for thunderbolt, that way they're easy for the average consumer to identify! Oh wait that's the issue USB was supposed to solve in the first place....

My hope is that Type-C is going to be all of those things so that in the future, I only need one kind of cable (until the inevitable new plug that supplants it, but hopefully universally used as well). Currently, I have to pay attention to a USB3 Type-C cable vs a Thunderbolt 3 cable as there is a difference (I was shopping for a long TB3 cable and was unable to find one. Instead, seems the longer ones tend to be USB…

This is one of those "it's a bug, not a feature" things. I don't mind having unified connectors so long as we have segregation between powered/unpowered connections at the cable level. It prevents faults by design.

There's no reason that an unpowered device should have the same connector as a powered one, and quite a few reasons why it shouldn't.