USB and FireWireUniversal Serial Bus (USB) ports now appear on desktop systems and laptops. Up to 127 devices can be connected to the system unit via a USB hub, which provides multiple USB ports. These devices include mouse, keyboard, scanner, printer, digital camera, and hard disk drive. One of the most convenient features of a USB port is its support for "hot connectivity," which allows peripherals to be connected to the system, configured, and used without restarting the machine. Due to USB's ease of connectivity and its ability to standardize many different devices into one cabling specification, USB has become the replacement for serial and parallel ports. Compared to USB 1.1, FireWire has a faster data transfer rate, and it supports up to 63 devices. FireWire is intended for data-intensive devices such as DVD players and digital camcorders. Peripheral devices can be connected via chaining. It also supports "hot connectivity." However, it is relatively more expensive than USB. The peak data transfer rate for USB 1.1 was 12 Mbps, and the peak data transfer rate for FireWire 400 (1394a) is 400 Mbps. In response to Firewire's fast data transfer rate, USB 2.0 was developed with a peak data transfer rate of 480 Mbps. To compete with USB 2.0, FireWire 800 (1394b) was developed with a peak data transfer rate of 800 Mbps. Parsons/Oja, Chapter 2-Section D, Figure 2-49 of the course textbook lists some of the cable connectors that peripheral devices use to connect to system ports.
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