USB Hub, Electronics Hub

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					                             A USB hub is a device that expands a single
USB port into several so that there are more ports available to connect
devices to a host system. Needless to say, the USB Hubs play an
irreplaceable and significant role in the updating electronics world. But
I bet we far from tech-savvy guys have no clear idea of the specific and
crucial role, then let's crack it on the strength of the elaborate
information on the internet.USB hubs are often built into equipment such
as computers, keyboards, monitors, or printers. When such an Input
Devices has many USB ports they all usually stem from one or two internal
USB hubs rather than each port having independent USB
circuitry.Physically separate USB hubs come in a wide variety of form
factors: from external boxes (looking similar to a network hub)
connectible with a long cable, to small designs that can be directly
plugged into a USB port (see the 'compact design' picture). In the middle
case, there are "short cable" hubs which typically use an integral 6 inch
cable to slightly distance a small hub away from physical port congestion
and of course increase the number of available ports.Laptop computers may
be equipped with many USB ports, but an external USB hub can consolidate
several everyday devices (like a mouse and a printer) into a single hub
to enable one-step attachment and removal of all the devices.A USB
network is built from USB hubs connected downstream to USB ports, which
themselves may stem from USB hubs. USB hubs can extend a USB network to a
maximum of 127 ports. The USB specification requires that bus-powered
hubs may not be connected in series to other bus-powered hubs.USB ports
are often closely spaced. Consequentially plugging a device into one port
may physically block an adjacent port, particularly when the plug is not
part of a cable but is integral to a device such as a USB flash drive. A
horizontal array of horizontal sockets may be easy to fabricate, but may
cause only two out of four ports to be usable (depending on plug
width).Port arrays in which the port orientation is perpendicular to the
array orientation generally have fewer blockage problems. "Octopus" or
"Squid" hubs (with each socket at the end of a very short cable maybe 2
inches long), or "star" hubs (with each port pointing in a different
direction, as pictured) avoid this problem completely.Well, against the
backdrop of electronics technology developing by leaps and bounds, we
contemporaries should keep abreast of its step and pay more attention to
the state-of -the-art electronics products hitting the Online Marketplace
or real stores market, contributed by the advanced technology and all the
more take full advantage of them to enrich our life.Source

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