A typical home network is given in the diagram below:
- As seen from the diagram above, a home network consists of Wired (desktop computers) and wireless (laptops) end stations, a wireless Access point (AP), a Layer 2 (L2) switch and a Layer 3 (L3) router.
- The end stations can communicate (exchange data) either with other end stations within the home or with end stations outside the home. For e.g. a file can be transferred from a wireless laptop to a wired desktop, a web page can be downloaded to the desktop from an external computer via. the internet etc.
- The L2 switch provides connectivity between the different end stations in the home, for data exchange purposes.
- Additionally, a wireless AP is required for connecting the wireless end stations to the L2 switch. The wireless AP acts as a base station for the wireless nodes inside the home.
- A L3 Router connects the home network to the public data network (internet) by connecting to a local ISP (Internet Service Provider)
- In general, a L3 Router is used to connect different networks. In the case of a home LAN, the router connects the private home network to the public data network.
- Hence, all data packets going from the home network to the internet and all data packets coming from the internet to the home network have to pass the L3 Router. The L3 Router acts as the home gateway.
- The L3 Router would typically have an Ethernet LAN interface that connects it to the internal home LAN and it would have a DSL/Cable interface to connect it to the local ISP.