Cheap USB Hub - Wireless USB Hubs - Laptop USB Hubs Wholesale
- Welcome to one-stop China USB Hubs wholesale market, we sell Cheap USB Hubs, Wireless USB Hubs, Laptop USB Hubs, USB Ethernet Hubs, USB Port Hub, Network USB Hubs, High Speed USB Hubs, Mini USB Hub, Wifi USB Hub from China Electronic Shop. For sample or small order, please purchase online. For large order, please contact us.
Port USB Hubs Wholesale
- New Wholesale Products
A USB hub is a device that allows many USB devices to be connected to a single USB port on the host computer or another hub. At present, most USB hubs belong to USB 2.0, and they are in high speed. Different USB hubs may have different numbers of ports, 2 port / 3 port / 4 port / 7 port are common in today's market.
USB hubs are often built into equipment, normally keyboards, or monitors or printers. Separate USB hubs come in a wide variety of form factors from boxes that look similar to a network hub to small designs intended to be plugged directly into the USB port on a computer (that is, without a connecting cable).
Each hub has exactly one upstream port and a number of downstream ports. The upstream port connects the hub (directly or through other hubs) to the host. Other hubs or devices can be attached to the downstream ports.
During normal transmission, hubs are essentially transparent: data received from its upstream port is broadcast to all devices attached to its downstream ports; data received from a downstream port is generally forwarded to the upstream port only. This way, what is sent by the host is received by all hubs and devices, and what sent by a device is received by the host but not by the other devices (an exception is resume signalling).
Hubs are not transparent when dealing with changes in the status of downstream ports, such as insertion or removal of devices. In particular, if a downstream port of a hub changes status, this change is dealt with an interaction between the host and this hub; the hubs between them act as transparent in this case.
Related Categories: Web Camera HDD Enclosures Bluetooth Dongle Digital TV Receiver Cool Parts PC & Notebook Accessories USB Flash Disk VOIP Skype Phone Wifi Keyboard & Mouse Joysticks