What is the purpose of a default gateway in a network?

The purpose of a default gateway in a network is primarily to route traffic to external networks. When a device on a local network wants to communicate with a device outside its own subnet, it sends the packet to the default gateway. The default gateway acts as an access point or route through which external traffic is directed, allowing the device to communicate with other networks, such as the internet.

A default gateway is essential for enabling devices within a local area network (LAN) to reach IP addresses that are not on the same network segment. Without a default gateway, a device would only be able to communicate with others on its local subnet, effectively isolating it from the wider network and internet services.

The other choices focus on aspects not directly related to the core functionality of a default gateway. Connecting multiple subnetworks is typically managed by routers, while IP addressing is handled by DHCP servers or through static IP assignment. Monitoring network performance involves tools and protocols that assess the state of the network rather than routing traffic.