What is the Difference Between Hubs, Switches and Routers

The functions of a router, hub and a switch are all quite different from one another, even if at times they are all integrated into a single device. Lets start with the hub and the switch since these two devices have similar roles on the network. Each serves as a central connection for all of your network equipment and handles a data type known as frames. When a frame is received, it is amplified and then transmitted on to the port of the destination PC. The big difference between these two devices is in the method in which frames are being delivered.

In a hub, a frame is passed along or broadcast to every one of its ports. It doesn't matter that the frame is only destined for one port. The hub has no way of distinguishing which port a frame should be sent to. Passing it along to every port ensures that it will reach its intended destination. This places a lot of traffic on the network and can lead to poor network response times.

however, switch keeps a record of the MAC addresses of all the devices connected to it. With this information, a switch can identify which system is sitting on which port. So when a frame is received, it knows exactly which port to send it to, without significantly increasing network response times. And, unlike a hub, a 10/100Mbps switch will allocate a full 10/100Mbps to each of its ports. So regardless of the number of PCs transmitting, users will always have access to the maximum amount of bandwidth. It's for these reasons why a switch is considered to be a much better choice then a hub.

A router is typically connected to at least two networks, commonly two Local Area Networks or Wide Area Networks or a LAN and its ISP (internet service provider) network . for example, your PC or workgroup and EarthLink. Routers are located at gateways, the places where two or more networks connect. Using headers and forwarding tables, routers determine the best path for forwarding the packets.

All routers have a Wide Area Network or WAN Port that connects to a DSL or cable modem for broadband Internet and the integrated switch allows users to easily create a Local Area Network or LAN. This allows all the PCs on the network to have access to the Internet and Windows file and printer sharing services. Some routers have a single WAN port and a single LAN port and are designed to connect an existing LAN hub or switch to a WAN. Ethernet switches and hubs can be connected to a router with multiple PC ports to expand a LAN. Depending on the capabilities of the router and the switches or hubs, the connection between the router and switches/hubs may require either straight-thru or crossover cables. Some routers even have USB ports, and more commonly, wireless access points built into them. Some of the more high-end or business class routers will also incorporate a serial port that can be connected to an external dial-up modem, which is useful as a backup in the event that the primary broadband connection goes down, as well as a built in LAN printer server and printer port.