International dialling prefix. Contents. An international dialling prefix is a telephone dialling code used to dial out of a country when making an international call. It's also called international access code, International Direct Dialling (IDD) code, exit code, international call prefix, etc.
Routers are small electronic devices that join multiple computer networks together via either wired or wireless connections. In technical terms, a router is a Layer 3 network gateway device, meaning that it connects two or more networks and that the router operates at the network layer of the OSI model. Routers contain a processor (CPU), several kinds of digital memory, and input-output (I/O) interfaces.
The main purpose of a router is to connect multiple networks and forward packets destined either for its own networks or other networks. A router is considered a Layer 3 device because its primary forwarding decision is based on the information in the Layer 3 IP packet, specifically the destination IP address.