A router is a specialized computer that has been designed specifically to send data to and from computer networks. It uses border gateway protocol, the routing protocol of the Internet, to communicate with the networks. An edge router, also known as an access router or a boundary router, transfers data between a local area network and a wide area network, choosing the most effective paths to use when sending or receiving data. It gets its name from the fact that it sits at the periphery, or edge, of a network.
There are different types of edge routers that perform various duties. A label edge router, for example, is used with a Multiprotocol Label Switching (MPLS) network. The router assigns labels to outgoing data by using the information included in the data to determine the correct label to use. It then attaches that label to the data before sending it to the network. When receiving data, the router removes any attached labels and then directs the data to the proper place. These routers and MPLS are used in large-scale networks, typically found in larger tech-oriented industries, because they improve the forwarding speed of data through the routers.
An aggregation router is another type of edge router that receives data from multiple sources, such as virtual private networks and frame relays, and combines them into one group before forwarding to a core router. Aggregation routers also can divide workloads evenly between multiple computers on the same network with a process called load-balancing. This makes aggregation routers beneficial to both large and small businesses because even workload distribution maximizes available bandwidth and avoids overloads.
A wireless edge router is a type that is connected to either a DSL Internet connection or a broadband cable. It uses radio airwaves instead of cables to transfer information — the computer’s data is turned into radio signals and sent to the wireless edge router. The router reads the information and uses a wired connection to transmit the data to the Internet. The wireless router also receives information from the Internet, which it turns into radio waves and sends to the computer.
In addition to routing information, an edge router also can provide security for the core network by being the point of access for data; it controls the flow of information into and out of the network. This function makes the edge router important to the network system; for this reason, it normally is designed with redundant features to decrease system failures.