up:: [[Computing MOC]] tags:: #on/computing/networking # Network Devices ## What is a Network? - A telecommunications network that allows nodes to share resources - *Node*: any device that connects to a network - *Resource*: anything that can be accessed or used over a network - *Local Area Network (LAN)*: a group of interconnected devices in a limited area - *Wide Area Network (WAN)*: a network that extends over a large geographical area (the Internet is one example) ## Types of Network Devices | Device | Role | | -------- | ---------------------------------------------------- | | Client | Device that accesses services provided by a server | | Server | Device that provides services for clients | | Switch | Connect devices within a LAN | | Router | Connect LANs together | | Firewall | Protect networks by denying certain types of traffic | ### Clients and Servers Clients and servers are nodes that share resources over a network. *Clients* access services that are provided by *servers*. Both are also often called *endpoints* or *end hosts*. > [!note] > Clients and servers are not specific types of physical devices. They are roles. Any physical device can be a client or a server, depending on what it is doing. A device can also be both a client and a server at the same time. ### Switches A *switch* is a device that connects devices within a LAN. Devices connected to a switch can communicate with each other via the switch. Devices don't usually communicate with the switch itself. The switch only serves as infrastructure over which communication can occur. ### Routers A *router* is a device that connects LANs together. ### Firewalls A *firewall* is a device that protects networks by denying certain types of network traffic. ## References McDowell, Jeremy. _Acing the CCNA Exam_. Manning, 2024. --- > [!createdat] Created at: [[2025-07-30]]