The primary function of the default gateway in a network is to forward traffic to different subnets. It acts as an intermediary that routes traffic from a local network to other networks, including the Internet. * Default Gateway: A router or network device that routes traffic from a local subnet to other subnets or networks. It serves as an access point or IP router that a networked computer uses to send information to a computer in another subnet or network. References: Cisco DevNet Associate Certification Guide, Chapter on Networking Basics and IP Routing.