This site may earn affiliate commissions from the links on this page. Terms of use.

USB-C-Feature

There'due south an old XKCD comic that brilliantly captures the difficulty of creating a single unified standard to control all device interactions or capabilities. It's not an entirely impossible goal–USB-A has dominated the market place for keyboards, mice, thumb drives, and a number of other peripherals for many years–but the larger the scope of the projection, the more difficult it is to bring every device under the same roof.

In a contempo blog postal service, Marco Arment–whose piece of work nosotros've covered in various articles before–argues USB-C is effectively chasing an impossible dream with its starry-eyed goal of unifying almost every other standard into a single diminutive cable. And based on what we've seen in the market merely then far, he's got a bespeak.

standards

Comic past xkcd

When Intel announced USB-C would carry Thunderbolt 3, it seemed like a great friction match-up. USB-C had already positioned itself every bit a cable and plug standard capable of carrying everything from ability to video, and Thunderbolt iii had bandwidth and low-latency operation capabilities that no other standard has yet matched. But the reality of USB-C (USB Type-C if nosotros're being technically correct) is that the various cable standards have created a nightmare of cables and products with widely varying compatibility and capability, all wrapped up in the aforementioned physical cables. If having to buy a bunch of standard-specific cables is bad, needing a bunch of standard-specific cables that all look identical is worse. As Arment writes:

USB-C commonly transfers data past the USB protocol, but it also supports Thunderbolt… sometimes. The 12-inch MacBook has a USB-C port, but information technology doesn't support Thunderbolt at all. All other modern MacBook models support Thunderbolt over their USB-C ports… just if you have a 13-inch model, and information technology has a Touch Bar, then the right-side ports don't have full Thunderbolt bandwidth.

If you bought a USB-C cable, it might back up Thunderbolt, or it might not. In that location's no way to tell by looking at it… While a broad variety of USB-C dongles are available, most apply the same handful of unreliable, mediocre chips within. Some USB-A dongles brand Wi-Fi drop on MacBook Pros. Some USB-A devices don't work properly when adjusted to USB-C, or only work in certain ports. Some devices only work when plugged directly into a laptop'due south precious few USB-C ports, rather than whatsoever hubs or dongles. And reliable HDMI output seems nearly impossible in practice.

Problems similar this are why Google Pixel engineer Benson Leung created his ain database of cables he'd tested, to determine which of them were compatible with USB-C as properly implemented and which were not. The amount of publicity his efforts earned, and the occasionally cataclysmic failure of the products he tested, weren't unusual only par for the course. The central problem is this: There are an enormous number of types of USB-C cables, and their capabilities and features aren't stacked direct on meridian of one another.

Before USB-C, backwards compatibility was much simpler. There were certain edge cases–a device that used USB iii.0 for power, for example, might need a compatible cable and a genuine USB three.0 port, though a handful of devices with USB two.0 ports delivered power to them via a specific "high ability" port. But with USB-C, your cable might back up ability delivery, simply not Thunderbolt. Information technology might support USB Type-C, but not USB 3.one. There are four unlike Alternate Modes: HDMI, DisplayPort, MHL, and Thunderbolt, and a cable supporting one of them doesn't mean it supports the others. There's a matrix on Wikipedia that shows the differences:

That's just for cables that support Alternate Modes, mind you–and not all do. As Arment details, compatibility between different products and standards ranges from functional to terrible.

Too Many Cooks in the Kitchen

Every standard has to strike a balance between cost, capability, and flexibility. In theory, the USB-IF could've mandated one USB-C standard in which every single feature was supported at every level. The trouble with this choice is that it would've kept cable prices high.

Building a USB-C cable that can handle delivering up to 100W of power and supports Thunderbolt 3 is more expensive than a cable that supports USB 2.0 transfer speeds and charging via USB-C. Cable lengths would have had to exist much shorter, since delivering that kind of adequacy over a long wire is much more hard than the USB 2.0 option. And taking a step like this would've made it much less probable companies would adopt the standard, since few mobile phones send with USB 3.0 chipsets (for case), and companies would've been much less interested in being forced to use a solution that consumes much more power than traditional USB. Beingness forced to packet a cable with a bunch of support for features your telephone doesn't use isn't going to win OEM support, either.

Merely therein lies the problem. In this case, the flexibility of USB-C actually makes information technology less probable that we'll meet the port take over everything. It'due south confusing, it'due south vastly more complex than any previous USB standard, and it's not doing consumers any detail favors.