Also known as: default route, gateway
Quick Definition
The IP address of the router a host sends packets to when the destination is on a different subnet.
The default gateway is the IP address of the router interface on the same subnet as the host. When a host wants to communicate with a device on a different subnet, it forwards the packet to the default gateway. The router then uses its routing table to determine how to reach the destination. Without a correctly configured default gateway, a host can communicate within its local subnet but cannot reach any other network.
A misconfigured or missing default gateway is one of the first things to check when troubleshooting connectivity issues. A host with no default gateway can still ping devices on its own subnet.
A Layer 2/3 protocol that maps known IP addresses to unknown MAC addresses.
A 32-bit value that divides an IP address into the network and host portions.
A manually configured route that does not update automatically when the network changes.
A Cisco proprietary FHRP that provides a virtual IP gateway shared by an active and standby router.
The default gateway is the IP address of the router interface on the same subnet as the host. When a host wants to communicate with a device on a different subnet, it forwards the packet to the default gateway. The router then uses its routing table to determine how to reach the destination. Without a correctly configured default gateway, a host can communicate within its local subnet but cannot reach any other network.
A misconfigured or missing default gateway is one of the first things to check when troubleshooting connectivity issues. A host with no default gateway can still ping devices on its own subnet.
Default Gateway falls under the IP Addressing domain of the 200-301 exam. Understanding it in context with related terms like arp and subnet-mask is essential for answering scenario-based questions correctly.