An edge device is any piece of hardware that controls data flow at the boundary between two networks. Edge devices fulfill a variety of roles, depending on what type of device they are, but they essentially serve as network entry (or exit) points. Some common functions of edge devices are the transmission, routing, processing, monitoring, filtering, translation and storage of data passing between networks. Edge devices are used by enterprises and service providers.
Cloud computing and the internet of things (IoT) have elevated the role of edge devices, ushering in the need for more intelligence, computing power and advanced services at the network edge. This concept, where processes are decentralized and occur in a more logical physical location, is referred to as edge computing.
Types of edge devices
One of the most common types of edge devices is an edge router. Usually deployed to connect a campus network to the internet or a wide area network (WAN), edge routers chiefly function as gateways between networks. A similar type of edge device, known as a routing switch, can also be used for this purpose, although routing switches typically offer less-robust features than full-fledged routers.
Firewalls can also be classified as edge devices, as they sit on the periphery of one network and filter data moving between internal and external networks.
Within a local area network (LAN), switches in the access layer -- that is, those connecting end-user devices to the aggregation layer -- are sometimes called edge switches.
Uses of edge devices
While the primary function of edge devices is to provide connectivity between disparate networks, the edge has evolved to increasingly support advanced services. These may include wireless capabilities, security functions, Dynamic Host Configuration Protocol (DHCP) services, domain name system (DNS) services and even analytics.
Cloud computing and IoT, in particular, have demonstrated the value for pushing intelligence to the periphery of the network. If an enterprise has thousands of IoT devices, it is not efficient for them all to try to communicate with the same resource at once. Edge devices can collect, process and store data in a more distributed fashion and closer to endpoints -- hastening response times, reducing latency and conserving network resources.