Basic but very important Interview Questions about Routers, Routing, & Routing Protocols.
Can you explain the concept of PDU, Segments, Datagram, Frame and packet?
What is IP datagram fragmentation and MTU?
Can you explain in detail with example how data fragmentation works?
Larger the IP datagram less the overhead, is it true or false?
What is the minimum size of MTU bytes?
Can you explain how optimal MTU size is calculated?
How does the IP message finally reassemble?
Can you explain the concept of Repeaters, Hubs, Bridges, Switches and Routers?
On what layers do router , switched , bridges and hubs operate ?
Can you explain the concept of Layer 3 switches?
what are CSU, DSU and TSU?
what are the basic components of the router?
Can you explain the WAN and LAN Interface in Routers?
What are DB-15, DB-60 and RJ-45 in CISCO routers?
Can you explain the concept of TTL?
What is the concept of ICMP packets?
Which operating system does CISCO have?
Can you explain the concept of NAT?
How is NAT implemented?
Can you explain how actually NAT works?
why does collision occur in HUBS and repeaters?
Can you explain the concept of Collision domain?
What is the concept of routing tables?
what is the use of route print?
Can you explain how in detail how routing table looks like?
How can you see route tables on the router?
Can you explain the concept of static and dynamic routing?
When to use Static routes and dynamic routes?
How do you configure static routes on a router?
Can you explain static default routes?
What is the advantage of using Static default routes?
Why do workstations have route tables?
What is the concept of gateway of last resort?
Can you explain the concept of routing protocol?
What activities does routing protocol perform?
What metrics are used by routing protocols to determine the best path?
Can you explain what is interior and exterior routing protocols?
Can you explain the concept of intradomain and interdomain routing protocols?
Can you explain the concept of internetwork and intranetwork routing protocols?
Which method does routing protocol use to determine shortest path?
What is distance vector routing protocol?
How do router share information in Distance Vector routing?
What is the main issue with routing by rumor?
Can you explain the count-to-infinity problem in distance vector?
How is metric or the cost calculated for Distance Vector routing protocol?
What is the main issue with hop count metric issue?
Can you explain how Link-State routing protocols work?
Can you explain the concept of broad cast and multi-cast?
Can you tell which protocols lie in Distance vector and which in Link- State?
What’s the difference between distance vector and link-state protocol?
Can you explain difference between Single path and Multipath?
Can you explain route summarization?
How are the series of IP combined in to one route path in route summarization?
Can you explain RIP protocol?
How is route table populated by RIP protocol?
Can you explain convergence in networks?
Can you explain RIP timers in detail?
Can you explain routing loop issue in RIP protocol?
How do we avoid routing loop issue in RIP?
In RIP why do we have HOP count of 15?
How do we disable auto-summarization in RIP?
Can you explain IGRP?
How does IGRP work?
How many timers does IGRP have?
How does IGRP calculate metric?
Can multiple instance of IGRP run on one physical router?
How is load balancing done in IGRP?
What’s the command to configure IGRP?
Can you explain EIGRP?
What does neighbor terminology mean in EIGRP?
What are different types of packets in EIGRP?
How does EIGRP protocol update route information to its neighbors?
What is the concept of successor in EIGRP?
What is DUAL in EIGRP?
Can you explain reported distance (RD), feasibility distance (FD) and
Feasibility condition (FC)?
Can you explain the concept of successor and feasible successor?
Can you explain passive and active route states?
What is SIA or stuck in active?
How do packets and timers in EIGRP work?
What are the different tables used in EIGRP?
Can you explain EIGRP metrics?
Can you explain how EIGRP finds its successor and feasible successor?
Can you explain Active and Passive route?
Can you explain OSPF?
How does OSPF populate route table?
What are the different tables in OSPF?
Can you explain different areas in OSPF?
Can you explain different router types in OSPF?
Can you explain Designated Router and Backup designated router?
Can you explain different router states in OSPF?
Can you explain different OSPF packet types?
What are the different types of OSPF timers?
How SPF algorithm does the route determination?
Can you explain autonomous system?
What are different types of dynamic protocols?
Can you explain autonomous numbers in EGP?
What is BGP?
What is the concept of BGP speakers and Peers?
What is EBGP and IBGP?
What is RIB?
Can you explain the concept of BGP confederations?
What are BGP path attributes?
What is the concept of NLRI?
How are routing neighbors discovered in BGP?
Can you explain how BGP does the decision process?
What is the concept of redistribution?
Can you explain the concept of one way redistribution and mutual ?
How does metric translation takes place in redistributing routes?
