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USB C: One Cord to Rule Them All

SAN  FRANCISCO — This is the wire you've been waiting for.

Earlier this week, the USB Implementers Forum — the governing body for the USB (Universal Serial Bus) standard — showed prototypes of its long-awaited USB C cable, which has connectors that you can insert upside down and which can carry up to 100 watts of power and 10 Gbps of data. The organization also released a new standard that allows vendors to add custom functionality to USB, perhaps opening the door for a cable that carries other types of data.

USB C flips for you

How many times have you tried to plug a USB cable into your notebook or phone and found you had to flip it over because it was upside down? The USB C connector is the same on the top and bottom, allowing you to plug it in using either orientation. You can even twist the wire and have one side of the cable plugged in one way and the other side connected the opposite way.

The dizzying variety of port sizes is another huge USB annoynace. Among A connectors, B connectors and micro, mini and full size, not to mention the occasional custom connector, it can be hard to figure out which wire you need. USB C comes in only one size, with a head that's around the same form factor as today's microUSB. If USB C becomes the standard, you'll only need one style of connector for everything.

We had a chance to handle a few early-production USB C cables. They looked solid and very similar in size and thickness to today's microUSB wires.

MORE: How to Connect USB Storage Devices to Your Android Phone

Alternate Modes

Companies and standards groups will now be able to add custom functions, officially called Alternate Modes, to USB C cables, provided that they register with the USB-IF. In theory, a company could manufacture USB cables that double as Thunderbolt wires or meet some other non-USB standard.

USB Power Delivery 2.0

Imagine using your USB cable, instead of that proprietary power brick, to power your laptop. We've long been excited about the USB PD (USB Power Delivery) standard, which offers 100 watts of power over the same cable that sends your data.

The USB-IF has now refined the specification to work with its new cables and with Alternate Modes. With USB C ready to roll, it looks like manufacturers may finally get on board and start producing laptops, monitors and other devices that offer power delivery with the reversible connector.

USB 3.1

Also known as SuperSpeed USB Plus (say that three times fast), the USB 3.1 standard doubles the maximum theoretical bandwidth of USB from the current 5 Gbps (gigabits per second) found on USB 3 to a new high of 10 Gbps, equivalent to 1,250 MBps (megabytes per second) because each bit is composed of 8 bytes.

In a private briefing, the USB-IF showed us a demo where a USB 3.1 controller from ASmedia was able to achieve real-world 803 MBps read and 833 MBps write rates using the Crystal DiskMark test, about double the data-transfer rate of the fastest USB 3 connection.

An organization representative told us that final USB 3.1 hardware will likely be even faster, approaching 1 GBps. With that kind of speed, an external SSD could be just as fast or faster than the one on the inside.


Though we've been hearing about USB 3.1 and USB Power Delivery for over a year now, these critically important standards could finally be close to shipping. Manufacturers have been waiting to combine the two technologies with the USB C connector rather than implementing them with the existing plugs. Now that we finally have a universal connector, we can have one wire that combines fast speeds, high wattage and reversible plugging.