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LFCS · Question #68

What is true regarding a default route?

The correct answer is C. The default route is only used if there is not a more specific route to a destination host or network. A default route serves as a gateway for all traffic to destinations for which no more specific route is defined in the routing table.

Submitted by valeria.br· Apr 18, 2026Networking

Question

What is true regarding a default route?

Options

  • AThe default route is always used first. When the default route is not available more specific routes
  • BWhen a default route is set, all other routes are disabled until the default route is deleted.
  • CThe default route is only used if there is not a more specific route to a destination host or network.
  • DWithout a default route, no network communication even in directly attached networks is possible.

How the community answered

(42 responses)
  • A
    2% (1)
  • B
    2% (1)
  • C
    95% (40)

Why each option

A default route serves as a gateway for all traffic to destinations for which no more specific route is defined in the routing table.

AThe default route is always used first. When the default route is not available more specific routes

The default route is used *last* among available routes, only after more specific routes have been considered and found not to match.

BWhen a default route is set, all other routes are disabled until the default route is deleted.

A default route does not disable other routes; rather, more specific routes take precedence over the default route.

CThe default route is only used if there is not a more specific route to a destination host or network.Correct

The routing table prioritizes the most specific route available for a destination. The default route, often represented as `0.0.0.0/0` or `::/0`, acts as a "catch-all" and is only used if no other, more specific route matches the destination IP address of the outgoing packet.

DWithout a default route, no network communication even in directly attached networks is possible.

Without a default route, communication to networks *not directly attached* or for which no specific route exists is impossible, but communication within directly attached networks can still occur.

Concept tested: Default route function

Source: https://learn.microsoft.com/en-us/windows-server/networking/technologies/ip-basics/understand-tcp-ip-addressing-and-routing

Topics

#Default Route#Network Routing#Routing Table#Longest Prefix Match

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