Guide to USB Cables

Get the 411 on how USB cables work

Today, all new computers come equipped with several USB slots or ports that accommodate the A end of the USB cable, while peripherals have a slot that takes the smaller B end of USB 2.0 cables. The computer is the host and data flows upstream through the A connector toward the computer and downstream through the B connector toward the device. When you connect a USB device to the computer for the first time, the operating system recognizes it and asks for drivers (plug and play).

I recommend: USB Stuff offers a wide variety of USB cables and connectors and USB extensions. If you still use devices or peripherals with serial or parallel ports, A1 Net Inc. carries both USB to parallel adapters and USB to serial adapters.

Types of USB cables and connectors

USB printer cables are the same size as USB cables for scanners. However, smaller devices like cell phones and cameras need smaller connectors, specifically the mini B connector. The A to mini B cable, as it is called, usually comes packaged with the device.

I recommend: Cables To Go's USB page is devoted to USB cables and connectors, including those for cameras and other small devices.

Use USB extension cables for distant devices

USB cables were designed to connect computers with devices in the same room. The USB cable transfers signals to a distance of 5 meters (about 16 feet, 5 inches) between high-speed devices and 3 meters (just under 9 feet) between low-speed devices. By using USB extension cables you can increase the distance between the computer and the device.

I recommend: BuyExtras.com offers 16-foot action repeater USB extension cables that amplify the USB signal to transmit over greater distances. The USB extension cables at QVS lets you connect devices up to a maximum of 150 feet apart.

USB hubs

While the USB port can support up to 127 devices, computers come with a limited number of USB ports, usually two to four. If you need to use more ports simultaneously, USB hubs are the answer. You simply plug USB hubs into the computer and plug additional devices into the hub. USB hubs, which can be chained together for additional connectivity, are either AC powered for use with high-power, high-bandwidth devices like external DVD burners, or unpowered for use with low-power devices like cell phones.

I recommend: USB Adapter offers USB hubs, including a 7–port USB 2.0 high-speed slim hub with AC power plus quantity discounts.  Laptops have even fewer USB ports than desktops. Cables To Go solves the problem with a portable, bus-powered, 4-port laptop hub. To connect two PCs together, CNA offers a USB PC to PC bridge.

USB cables versus FireWire cables

Similar to USB cables, FireWire cables are peer-to-peer rather than host-based, meaning that two devices can talk directly to each other without a host computer. FireWire and USB cables and ports have different configurations and are not interchangeable. USB is the dominant standard, especially in the PC world, although FireWire is favored for streaming digital video applications thanks to its ability to send uncompressed video with guaranteed bandwidth.

I recommend: Cables To Go offers a variety of USB hubs, including a USB/FireWire combo hub with four USB 2.0 ports and two FireWire ports.