Drag each description on the left to the appropriate term on the right.

Holddown timer – each router start a timer when they first receive information about a network that is unreachable. Until the timer expires, the router will discard any subsequent route messages that indicate the route is in fact reachable (verified). A holddown keeps a router from receiving route updates until the network appears to be stable

Split horizon is a method of preventing a routing loop in a network. Information about the routing for a particular packet is never sent back in the direction from which it was received.

Define a maximum count to prevent routing loops. The invalid updates of Network 1 will continue to loop until some other process stops the looping. To avoid count-to-infinity time, distance vector protocol define infinity as some maximum number.

Route poisoning — When a route to a subnet fails, the subnet is advertised with an infinite-distance metric. When a router detects that one of its directly connected routes has failed, it will advertise a failed route with an infinite metric (“poisoning the route”).

Triggered update improve the convergence time of RIP. The trigger is a change to a metric in an entry in the routing table. For example, networks that become unavailable can be announced through a triggered update. Also the triggered update is sent immediately, where a time interval to wait is typically specified on the router.