Routing Technologies & Protocols Flashcards
7 cards from real ICND1 practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Routing Technologies & Protocols flashcards as text
Which of the following best describes a classless routing protocol?
Answer: It includes subnet mask information in routing updates
Classless routing protocols include subnet mask (prefix length) in their updates, allowing support for VLSM and CIDR.
A router running OSPF shows a neighbor in 'EXSTART' state for an extended time. What is the most likely cause?
Answer: MTU mismatch between the two routers
An MTU mismatch prevents OSPF routers from successfully exchanging DBD packets, causing the neighbor to stall in EXSTART/EXCHANGE state.
What is the administrative distance of an EIGRP internal route?
Answer: 90
EIGRP internal routes have an administrative distance of 90, making them preferred over OSPF (110) and RIP (120).
Which statement about RIPv2 is true?
Answer: It uses multicast address 224.0.0.9 for updates
RIPv2 sends routing updates to the multicast address 224.0.0.9, unlike RIPv1 which used broadcast.
A Cisco router has the following routes: S 10.0.0.0/8, O 10.1.0.0/16, and C 10.1.1.0/24. Which route is selected for a packet destined to 10.1.1.50?
Answer: C 10.1.1.0/24 because it is the longest prefix match
Longest prefix match is always the primary selection criterion; 10.1.1.0/24 is the most specific match for 10.1.1.50.
Which OSPF LSA type describes routes external to the OSPF domain?
Answer: Type 5 (AS External LSA)
Type 5 LSAs are generated by ASBR routers to advertise routes redistributed from external routing domains into OSPF.
What happens when a RIP router receives a route update advertising a destination with a hop count of 16?
Answer: It treats the destination as unreachable and discards the route
In RIP, a hop count of 16 represents infinity, meaning the destination is unreachable and the route is not installed.