In computer networking, which configured address on a host identifies the local router that forwards packets to other networks?

Introduction / Context:
In a typical Internet Protocol (IP) local area network, hosts need a way to reach destinations that are not on their own subnet. The configured address that represents the local router for this purpose is known as the default gateway. Understanding what each common configuration field means prevents misconfiguration and connectivity loss.

Given Data / Assumptions:

• Host participates in an IPv4 network.
• Standard host settings include IP address, subnet mask, and default gateway.
• No special static routes beyond default gateway are configured.

Concept / Approach:
The default gateway is the layer-3 (IP) next hop for traffic whose destination is outside the host's local subnet. When the host determines a packet is nonlocal (via subnet mask comparison), it forwards the packet to the default gateway's IP (the router's interface on the local subnet).

Step-by-Step Solution:

Verification / Alternative check:
On most systems, show the routing table (e.g., route print or ip route). The default route points to the gateway's IP on the local network.

Why Other Options Are Wrong:

• The IP address: This is the host's own identity, not the router's next-hop setting.
• The TCP address: TCP is a transport-layer protocol; it has no addressing concept like an "address of the router".
• The subnet mask: This defines the boundary of the local network, not the router's address.
• None of the above: Incorrect because the correct term exists: default gateway.

Common Pitfalls:
Confusing the host's IP or DNS server with the gateway; using a gateway IP that is not on the same subnet as the host; leaving the gateway blank, which breaks off-subnet communication.

Final Answer:
The default gateway