In simple terms, a network device is a physical device that is used to connect other physical devices on a network. In some cases, their role is to simply forward packets of information to a destination. In other cases, it might be to serve as a translator or to block suspicious network traffic.
Common Types of Network Devices
The most common types of network devices include hubs, switches, routers, bridges, gateways, modems, repeaters, and access points. Below is a more detailed description of each of these devices.
Hubs are used to connect multiple network devices together. They can be used to transmit both digital and analog information. Digital information is transmitted as packets, whereas analog information is transmitted as a signal. Hubs also act as a repeater, which amplifies signals that have weakened after being transmitted across a long distance. Hubs operate at the Physical layer of the Open Systems Interconnection (OSI) model.
A switch is a multiport network device whose purpose is to improve network efficiency and improve communication between hubs, routers, and other network devices. Switches are intelligent devices that gather information from incoming packets in order to forward them to the appropriate destination. Switches generally have limited information about the other nodes on the network.
The main role of the router is to forward packets of information to their destinations. Routers are more intelligent than hubs or switches as they store information about the other network devices they are connected to. Routers can play an important role in network security, as they can be configured to serve as packet-filtering firewalls and reference access control lists (ACLs) when forwarding packets. In addition to filtering authorized network traffic, they also are used to divide networks into subnetworks, thus facilitating a zero-trust architecture.
A bridge is used to connect hosts or network segments together. As with routers, they can be used to divide larger networks into smaller ones, by sitting between network devices and regulating the flow of traffic. A bridge also has the ability to filter packets of data, known as frames, before they are forwarded. Bridges are not as popular as they once were, and are now being replaced by switches, which provide better functionality.
A gateway device is used to facilitate interoperability between different technologies such as Open System Interconnection (OSI) and Transmission Control Protocol/Internet Protocol (TCP/IP). In other words, they translate each other’s messages. You could think of a gateway as a router, but with added translation functionality.
A modem, which is short for “modulators-demodulators”, is a piece of network hardware that is used to convert digital signals into analog signals, in order to transmit them over analog telephone lines. When the signals arrive at the destination, another modem will convert the analog signals back to a digital format.
A repeater is a relatively simple network device that amplifies the signal it receives in order to allow it to cover a longer distance. Repeaters work on the Physical layer of the OSI model.
An access point (AP) is a network device that is similar to a router, only it has its own built-in antenna, transmitter and adapter. An AP can be used to connect a variety of network devices together, including both wired and wireless devices. Access points can be fat or thin. A fat AP must be manually configured with network and security settings, whereas a thin AP can be configured and monitored remotely.
Having at least a basic understanding of the different types of devices that exist on a typical network will help you develop a network topology that is available, efficient and secure. However, you should also use some sort of security event management system to ensure that you have visibility into any suspicious inbound and outbound network traffic, and other anomalous network events.
Securing network devices is just one piece of the puzzle. The attack surface has drastically changed over the last 5 years, with internal threats targeting Active Directory and working their way through to sensitive data stored on-premises or in cloud data stores. Schedule a demo to see how Lepide can help you start your data and identity security journey today.