A networking device that operates at Layer 3 of the OSI model. Routers are used to mix media types and are most often used to make WAN connections. Routers are sometimes referred to as gateways. A networking device that operates at layer 2 of the OSI model. Switches are used to provide connectivity to users on a LAN and to improve network performance over shared environments.
Switches can be small devices or can scale to have hundreds of connections.
Typically used in Ethernet environments. Hubs are used to enable multiple devices to share one 10MB or 100MB connection. Typically, firewalls are used to protect network assets from invasion by Internet users. Hubs enable you to add more users to a single collision domain. Switches enable you to segment collision domains.