Apple recently updated its MacBook Pro models. While users of the line will certainly be pleased with the new processors and video options, these were mostly catching up to the components already available on other laptop brands. The one genuinely unique feature of the laptops was the new Thunderbolt port. This is a new connector developed by Intel under Apple’s direction. It is generally thought that Apple is a year ahead of other PC makers in having this port on their computers.
That is presuming that the others use it at all.
Apple has a history of introducing new connectors. Some have been wildly successful, such as USB. Others soon landed in obscurity such as Apple Desktop Bus (ADB) and LocalTalk. Some found limited success like Firewire. And for some the jury is still out, such as DisplayPort.
Not every battle for the ‘next best’ necessarily results in a winner. Oldtimers might recall when IBM’s Micro-Channel and the clone makers’ EISA competed to be the next generation from the ISA cards and slots in desktop PCs. The winner was…neither. Functions that used to be on expansion cards, like disk controllers and networking, migrated to the motherboard itself and thus reduced the demands on the expansion slots. So the ISA connectors lived on for years before being replaced by PCI slots and now PCI-e.
One thing that I think is safe to say is that USB, and particularly USB 2, has been one of the most successful standards ever in the computer industry, and in large part that has been because of the notion of having one port type for just about anything: printers, external disk drives, cameras, keyboards, pointing devices, game controllers, and even things that hadn’t yet been invented, such as flash data storage devices and USB microphones.
But there have been some limits starting to show up. As hard disks went from ATA100 to SATA 150 to SATA 300 the USB 2 port has become a bottleneck on external hard disks. The power limits also have begun to show, which is why some external USB drives expect you to plug into two ports (the second is just to get more electricity). The ability to pop a memory card out of a camera and into a slot was just too convenient. And video was never part of the plan.
Thunderbolt, which Intel developed under the name LightPeak, uses a miniature version of Apple’s existing DisplayPort. However unlike the DisplayPort, which as you can tell by its name is only for displays, the Thunderbolt wire carries two signals at once. One is the Display channel, and the other is a PCI-e adapter signal. Each channel is described as having 10gb/sec capacity. Because the data channel uses PCI-e properly designed external devices should look just like they were attached to the internal bus of the computer or to a PCI-express card slot on a laptop. The cable also includes conductors for carrying up to 10 watts of DC power.
Whether or not the rest of the computer industry jumps on board the Tunderbolt bandwagon remains to be seen. There are alternatives.
The first alternative is called USB3. It offers improved speeds (although not as fast at Thunderbolt) plus the unique advantage of being plug-compatible and forwards and backwards compatible with USB 2. In other words you can plug a USB 2 device into a USB 3 port and a USB 3 device into a USB 2 port. Of course USB3 speeds are only genuinely obtained when plugging a USB3 device into a USB3 port, just as it was the case with USB 1.0 and USB 1.1. USB3. is not expected to carry video signals, but whether that represents a real problem remains to be seen. Apple does not expect USB to go away anytime soon. The MacBooks that debut the Thunderbolt port have USB ports, but they are USB 2 ports, notably not USB 3.
The other alternative is that there have been some specialty ports beginning to show up on computers to fill in the gaps in USB 2. The first were memory card slots. SD cards have become the common denominator among still and video cameras and it is just so convenient to be able to slip them into your computer to transfer the images. That reduces come of the demands on the USB ports. The new MacBooks also include a memory card slot in acceptance of this. Also desktop computers and occasionally laptops are beginning to have e-SATA ports for external drives. These have the advantage of being full-speed (simply an external connection right to the hard disk itself) and requiring no extra electronics on either end. Their only limitation is that they must have a separate power supply. But for the specific purpose of having an external hard disk they are simple, inexpensive, and fast. Then for display there is HDMI. This is an interface that has become a standard across numerous product categories:TVs, game consoles, Internet streaming video devices, blu-ray players, AV receivers, projectors, cameras, etc. I am guessing that one of the most common accessories for owners of DisplayPort and Thunderbolt equipped devices will be an HDMI or DVI adapter so they can use projectors or conference room displays.
As for HDMI ports one rule that has held pretty true in computers is that if something has become the standard in areas beyond the computer it has a huge head start on becoming the standard on computers too. For example there were numerous formats competing to be the next step up from the floppy drive, such as the Iomega Zip Drive. But recordable CD’s overwhelmed them because they were the standard for digital music. You could record a CD on your computer and (usually) play it in your stereo or car. Game Over for any of the competing recordable formats. Such is the case with HDMI. There are just too many no-adapter-required uses for an HDMI port to have the lack of one on a computer not be regarded as a disadvantage.
Thunderbolt also has another feature that I think will eventually be regarded as a negative. It supports up to seven devices per port in a daisy chain topology. A daisy chain topology means that you connect the port to the first device, then you connect the second device to the first device, the third device to the second device, and so on. That sounds sort of nice until you want to disconnect the first device without having to also disconnect all the others. By comparison the hub topology of USB makes it easier to disconnect any device without affecting the others. The daisy-chain topology comes from the DisplayPort and it does make some sense in a dual monitor situation to connect the second monitor to the first since they are already side-by-side. But not for general peripherals. Apple has tried daisy chain topologies for external devices before with ADB and LocalTalk, and each eventually were replaced with products with hub topologies (USB for ADB, and Twisted-Pair Ethernet for LocalTalk).
While Thunderbolt is undeniably faster than USB 3 there really isn’t any current or soon-to-be-expected desktop device that needs more speed than USB 3 can provide. Sometimes good-enough-for-now is, well, good enough for now.
So a year from now will the other PC makers be ‘catching up’ with Apple and offering a Thunderbolt Port on their computers or will Apple be announcing a MacBook Pro with USB 3 slots and a HDMI port? I would guess the latter.