This article was written by Don VanSyckel, the club president, as a part of "The President's Pen". This article appeared in the December 2023 WYSIWYG newsletter.
USB History
by Don VanSyckel
USB has been around since 1998 so it's about 25 years old. Starting with USB 1.0 and then moving through USB 1.1, USB 2.0, USB 3.0, and USB 3.2, with each advance moving the top speed higher. Now the specification for USB4 has been released and devices are beginning to appear that has this type port. USB 1.1 through USB 3.2 all have different speeds capabilities but are basically electrically the same. USB4 has a distinctly different electrical format and even the official name is different with no space between the "USB" and the "4". The table below is copied from a President's Pen I wrote for the WYSIWYG newsletter September 2013 and details USB types through USB 3.1.
| USB Type | Date | Bits/sec - X USB 1.1 | Bytes/sec | Comparability |
| USB 1.1 | 1998 | 12M - 1X | 1.5M | |
| USB 2.0 | 2000 | 480M - 40X | 60M | USB 1.1 |
| USB 3.0 | 2008 | 4 G - 330X | 500M | USB 1.1,2.0 |
| USB 3.1 | 2013 | 10 G - 830X | 1250M | USB 2.0,3.0 |
All USB types are backwards compatible including USB4. Even though the electrical characteristics when operating in the USB4 mode are different, USB4 ports can support the "old" style USB electrical operation so that USB4 ports are also backward compatible with the older USB type devices.
The USB4 mode has quite a few different modes of operating and can operate up to 120 G bits/second. This is a mere 10,000 times the speed of the original USB 1.1 port and 6 times the speed of a USB 3.2 port. USB4 ports can also support other protocols such a DisplayPort and PCI Express using a new feature called tunneling. I have not been able to find a good explanation of the details of USB4 tunneling so I can't give a further explanation of this. I can describe tunneling in general which is the use of one protocol of communication to transport information which is encoded and formatted in a different protocol.
All in all, USB4 has quite a few different modes of operation and from my reading it's not entirely clear to me the meaning of some of the differences. USB4 only uses the Type-C connector and has high power delivery capabilities. USB4 is optionally compatible with Thunderbolt 3. The Thunderbolt family of peripheral connectivity is used by Apple.
While the USB4 ports are much more complicated to understand the under the hood operation of, they are supposed to make life simpler by hiding all the details from users and allow them to simpley plug and go with higher speed. Of course this is all with the assuption that all the USB4 port implementations for both compurters and peripherals meet all the extremely complicated design specifications, we'll see.
End of Article