A Closer Look At Hub, Switch And Router

In Ethernet network deployment, there are three components which are similar in shape—hub, switch and router. All of them are small plastic or metal box-shaped electronic devices. However, they play different roles in the network. This article will guide you to have a closer look at hub, switch and router.

A hub, also called a network hub, is a common connection point for devices in a network. Containing multiple ports, the hub is commonly used to connect segments of a LAN. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

In a network, a switch filters and forwards packets between LAN segments. It usually operates at the data link layer (layer 2) and sometimes the network layer (layer 3) of the OSI Reference Model and therefore supports any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs.

A router is designed to join together multiple LANs with a WAN. Serving as intermediate destination for network traffic, the router receives incoming network packets, looks inside each packet to identify the source and target network addresses, then forwards these packets where needed to ensure the data reaches its final destination.

From the outside, hub, switch and router are identical:

• They are small plastic or metal box-shaped electronic devices.
• They make computers connect to them through network cable for getting access to the Internet.
• They have a number of physical ports on the front or back of the unit that provide the connection points for computers, a connection for electric power and LED lights to display device status.

But when applied in a network, there are some differences among them:

• We know that router is designed specifically to join the home network to the Internet for the purpose of Internet connection sharing. However, switch and hub are not capable of joining multiple networks or sharing an Internet connection. A network with only switch and hub must instead designate one computer as the gateway to the Internet, and that device must possess two network adapters for sharing, one for the home facing connection and one for the Internet facing connection.
• Router is smarter in other ways. For example, router is featured with integrated DHCP server and network firewall support. Some wireless routers even incorporate a built-in Ethernet switch for supporting wired computer connections (and enabling network expansion via connecting additional switches if needed).
• Router is the only one of these three devices that will allow you to share a single IP (Internet Protocol) address among multiple network clients.
• Switch is higher-performance alternative to hub. For example, both pass data between devices connected to them, hub broadcasts the data to all other connected devices, while switch first determines which device is the intended recipient of the data and then sends it to that one device directly via a so-called "virtual circuit". On busy networks, this behavior allows switch to generate less overall network traffic compared to hubs.

For home network deployment, switch and router are used more commonly, especially PoE switch and wireless router. I hope after reading this article, you can have a better understanding of hub, switch and router. FS.COM provides network cable with multiple lengths and colors for network cabling.