Routers and Ethernet switches help information to move from one computer to another by forwarding data over networks. The switch and the router have different capabilities and are usually deployed in different types of networks. Whereas a switch is always found on a Local Area Network (LAN), routers are needed for Wide Area Networks (WAN), especially the Internet.
Switches/Network SwitchesA network switch is an electronic box with a number of sockets or ports. Each computer in a network connects to a port on the switch via an Ethernet cable. No device can connect to a network without a network adapter. The network adapter has a serial number burned onto it. This unique number is the physical address, known as the MAC address, of the computer. It is appended to the front of all data packets traveling across a network. The packet contains the MAC addresses of both the source and destination computer for the packet. Network switches associate the MAC address of each connected computer to the socket to which that computer is connected. When one computer sends a data packet to the switch, the switch reads the destination address and sends the packet out on the socket associated with that address.
Routers/Cisco RoutersRouters send data around the Internet through a chain of links that forms a path. Each router has to be connected to at least two networks. One of those networks must contain at least one other router, which in turn should link to another router over another network. Routers use Internet Protocol (IP) addresses to direct data to the correct network. Any computer that can be contacted over the Internet has to have a unique IP address. A router collates a list of IP addresses and the various paths available to reach that point. Although the router calculates the best direction to forward the data, it does not dictate the whole path. It passes the data packet onto a neighboring router and that router then makes its own decision where to forward the data.
Routers vs. SwitchesRouters have greater capabilities than switches. They can operate over local networks as well as over the Internet. IP addresses assigned to computers on local networks do not need to be unique throughout the world, only on the LAN. The router keeps track of any messages leaving the network from a locally assigned address, which cannot be used over the Internet, and forwards the incoming response back to that request when it arrives. Both outgoing and incoming messages carry the router's IP address and not the locally assigned IP address of the originating computer. Routers operating over private networks offer extra security features, such as firewalls, for different segments of the network. Switches cannot provide these functions.
Routers with SwitchesRouters and switches usually work together. While the router commands the overall direction for a data packet, the switch guides data over one link of a network. Data packets usually pass through a router and a switch using both an IP address and a MAC address. Network gateways have to translate between the two addressing methods, using the Address Resolution Protocol.
access point vs router
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