Thunderbolt 3 and USB converge with new 40 Gbps USB4 specification

[Arthur]

Super Ultra Mega Speed USB?

 

Source: USB Promoter Group (PDF) (via Ars Technica, Tom's Hardware)

 

Fulfilling its 2017 promise to make Thunderbolt 3 royalty-free, Intel has given the specification for its high-speed interconnect to the USB Implementers Forum (USB-IF), the industry group that develops the USB specification. The USB-IF has taken the spec and will use it to form the basis of USB4, the next iteration of USB following USB 3.2.

 

Thunderbolt 3 not only doubles the bandwidth of USB 3.2 Gen 2×2, going from 20Gb/s to 40Gb/s, it also enables the use of multiple data and display protocols simultaneously. We would expect the USB4 specification to be essentially a superset of the Thunderbolt 3 and USB 3.2 specifications, thus incorporating both the traditional USB family of protocols (up to and including the USB 3.2 Gen 2×2) and the Thunderbolt 3 protocol in a single document. Down the line, this should translate into USB4 controllers that support the whole range of speeds.

 

Intel has previously announced that its Ice Lake platform, due to ship later this year, will integrate both Thunderbolt 3 and USB 3.1 Gen 2 (aka USB 3.2 Gen 2) controllers. Currently, offering Thunderbolt 3 requires the use of an additional chip, one of Intel's Alpine Ridge Thunderbolt 3 controllers. Integration into the platform means that system-builders no longer need to choose whether or not to include the extra chip; the capability will be built in, and as such, we'd expect to see it become nearly universal.

 

We should also take the opportunity to marvel once again at USB-IF's prowess for naming things. While previous versions included a space between "USB" and the version number—giving us "USB 3.2," "USB 2.0," and so on—with USB4 it has for some unfathomable reason decided to discard the space. This is the same organization that numbered successive USB 3 generations "Gen 1," "Gen 2," and "Gen 2×2," so nothing it does on the naming front should really surprise us, but the inconsistency is nonetheless quite remarkable.

 

The USB Promoter Group, the standards body behind the USB specification, announced it would step forward to the USB 4 architecture in the middle of 2019. The new speedy interface blends in Thunderbolt 3 support and offers twice the bandwidth of USB 3.2, meaning it supports up to 40 Gbps of throughput.

 

The USB specification is perhaps the most ubiquitous of interfaces in the computing industry. From mobile devices to laptops and desktop PCs, billions of devices have shipped that support the interface since its inception in 1995. Each step forward to a new specification, and the increased speed and compatibility that comes along with it, spurs a wave of new devices that range from cheap USB flash drives to new external storage enclosures. The USB interface has had its challengers over the years, but its royalty-free model and broad use, along with a steady cadence of higher speeds through improved specifications, has staved off the competition.

 

To further expand the range of devices using the Thunderbolt 3 specification, Intel has contributed its protocol to the USB standards committee, which integrated the protocol into USB 4. Intel's contribution comes without royalties, meaning that other chip manufacturers can build supporting silicon without paying a fee.

 

USB4 doubles throughput up to 40 Gbps across a two-lane interface with certified USB Type-C cables. The USB Promoter Group will also introduce a new USB Type-C Specification to handle USB 4 bus discovery.

 

Thunderbolt 3 integration also enables the simultaneous transfer of both data and display protocols, meaning that you can daisy-chain 4K monitors and other Thunderbolt 3 devices, like external storage or GPU enclosures, together into one cable that connects to your PC. Thunderbolt 3 passes data across four lanes of PCIe 3.0, while also supplying eight lanes of DisplayPort 1.2 that supports up to two 4K displays at 60 Hz. Thunderbolt 3 also provides up to 100W of power for system charging and 15W for bus-powered devices.

 

As expected, USB 4 will retain compatibility with USB 2.0 and 3.2, the latter of which was recently renamed in a bid to simplify the somewhat confusing USB naming schemes. The USB Promoter Group hasn't assigned a new marketing term for the interface (like SuperSpeed USB), though it plans to soon.

 

Intel has already announced that it is baking in support for the Thunderbolt 3 specification directly into its forthcoming 10nm Ice Lake processors, eliminating the need for third-party control chips. That tight level of integration builds upon the existing Thunderbolt 3 support in Windows 10 and macOS.

 

[...]

 

The USB 4 standard will be finalized in mid-2019.

 

Edited March 4, 2019 by Arthur

[XiJ]

Another new connection type. can’t we just make sure USB-C connectors are the norm first?

 

Maybe I’m getting old. Technology is moving too

Fast.

[Arthur]

Technology is moving too fast.

They should have waited a bit longer and based USB4 on a PCIe 4-based Thunderbolt 4 with a bandwidth of 80 Gbit/s.

 

Now we're probably going to end up with a USB5 / Thunderbolt 4 hybrid which will be a bit more confusing.

[Fazza]

Another new connection type. can’t we just make sure USB-C connectors are the norm first?

 

Maybe I’m getting old. Technology is moving too

Fast.

 

Isn't the future 'the cloud' so why are we even bothering with physical connectors any more?

[DalekSec]

Isn't the future 'the cloud' so why are we even bothering with physical connectors any more?

 

The cloud is just another persons computer A computer that might require USB 4.0 Speeds

[Fazza]

A computer that might require USB 4.0 Speeds

 

I hope not! They should be using DAS or SAN for cloud storage.

[Brimstone]

Isn't the future 'the cloud' so why are we even bothering with physical connectors any more?

Not for 4K Production Studios it's not.....