A "central hub" wired to every computer and network device in an Ethernet. In the home and small office, an Ethernet switch is built into the router.
10/100 and 10/100/1000
Gigabit Ethernet (10/100/1000) switches support 1 Gbps and also 10 Mbps and 100 Mbps for compatibility with lower-speed devices. Older 10/100 switches cannot handle Gigabit speeds; however, all Ethernet devices sense the speed of the connection and transmit at the highest common denominator.
Hubs and Switches
Although an Ethernet switch is sometimes called a hub, there is a huge difference between a true hub and switch. Most Ethernet hubs have been replaced with switches, vastly improving network throughput.
Unmanaged and Managed Switches
A basic "unmanaged" Ethernet switch has no user configuration. It is placed in the network; the cables are plugged in; the unit is turned on and there is nothing else to do. In contrast, for large company networks, a "managed" switch can be configured to adjust speeds, combine users in subgroups, monitor traffic and report network activity.
Carrier Ethernet switch engines and Enterprise Ethernet switches are used worldwide in networking equipment such as:
Carrier: Mobile base stations, cell site routers and gateways, IP Edge routers, microwave mobile backhaul systems, Carrier Ethernet switch/routers, aggregation switches and routers, and packet optical transport systems for telecommunications service providers delivering voice, video, data and video communications services to business, residential and mobile customers;
Enterprise: Managed Enterprise switches, stackable Enterprise switches, security appliances, and gaming consoles for networks ranging from large Enterprises, data center switching, small-medium enterprise (SME), small-medium business (SMB), and small office/home office (SOHO) for voice, data and video communications, as well as cloud access and cloud services;
Internet of Things: Industrial Ethernet switches for industrial process control, smart grid energy distribution, transportation, and automotive applications.