300+ [UPDATED] Cisco Network Engineer Interview Questions and Answers

Q1. List The Important Characteristics Of Igrp?

Multiple unequal paths, autonomous system number, etc.

Q2. What Are The Important Characteristics Of Isdn?

It trports both voice and data, and same as X.25

Q3. Which Abbreviation Is Used To Tell The Router To Check All Numbers?

  • host

Q4. How Can We Convert The User Data From Dte To Wan Service Form?

We can use the Modem, CSU/DSU and TA/NT1 for this.

Q5. Which Authentication Method Is Preferred To Set Up A Session?


Q6. Which Mechanism Takes Place In A Traffic Light?

Flow control

Q7. What Is The Use Of Cisco Ios Exec Command Trace?

The “trace [protocol] [destination]” is used to discover routes that packets will travel to their destination hosts. TTL (Time to Live) is used to report destination route information.

Q8. Which Hardware Component Is Used To Store Buffers, Tables, Etc.?


Q9. What Is Magic Number?

It helps avoid frame looping.

Q10. What Are The Cisco Hdlc Protocol.?

It contains the Flag, Address, Control, Proprietary, Data, FCS and Flag.

Q11. What Is The Range Of Extended Ip Access List?

The range is 100-199

Q12. What Is The Quality Protocol?

It monitors data dropped on a link.

Q13. How Many Access Lists Are Allowed Per Interface?

One Access list per port, per protocol is allowed.

Q14. How Can You Vary The Router Boot Sequence?

It can be done by boot system commands and config register.

Q15. What Are The Important Characteristics Of Ppp Pap Authentication?

Username and password is sent in clear text and The authentication controls remote node.

Q16. When Using Access Lists, What Does A Cisco Router Check First?

The cisco routers checks whether the packet is routable or bridgeable

Q17. Which Osi Layer Is Used For Physical Address And Network Topology?

The Data link layer serves this purpose.

Q18. What Is Source Quench?

It is the condition when the router lacks any more buffer space.

Q19. Name The Default Ipx Ethernet Encapsulation?

Novell-Ether is the default IPX Ethernet encapsulation.

Q20. Which Process Is Used To Find An Ip Address From A Mac Address?

RARP Process

Q21. What Is The Use Of Dlci?

It is used to identify the PVC in frame relay network.

Q22. How Can A Router Be Configured?

It can be configured by TFTP, Nvram or Console

Q23. Important Features Of Ppp Chap Authentication?

Authentication messages and local router challenges

Q24. What Is Icmp Protocol?

It is used to carry messages like destination unreachable, source quench, parameter problem, time exceeded, timestamp, address reply and address request.

Q25. What Do You Know About The Udp Datagram Format?

Source Port – 16 bits, Destination Port – 16 bits, Length – 16 Bits, Checksum – 16 bits, Data

Q26. Name And Explain The Phases Of Ppp Session Establishment.?

These are link establishment phase, authentication phase and the network layer protocol phase.

Q27. What Are The Important Features Of Udp?

It is the layer 4 trport protocol and has no handshaking.

Q28. What Is The An Important Feature Of Rarp.?

The full form of RARP is Reverse Address Resolution Protocol. It is used to start remote O/S load sequence.

Q29. What Is The Number Range Of Ipx Access List?

The range is 800-899

Q30. Why Do We Have To Disable Cdp?

To save the bandwidth by reducing overhead and to connect to a non cisco router.

Q31. Which Is The Ipx Serial Encapsulation By Default?


Q32. List The Default Values In Eigrp Metric?

The default values are bandwidth and delay.

Q33. What Is The Use Of Arp?

It is used to determine the MAC Address of a workstation.

Q34. Which Compression Protocols Are Used For Ppp?

Stac and Predictor

Q35. What Is The Access List Range For Extended Ip Access List?

The access list range is 100 – 199.

Q36. Which Format Is Useful For Configuring The Subnet Mask For An Ip Address?

dotted decimal, hexadecimal and bit count formats can be used.

Q37. Important Features Of Osi Layer 3 – Network Layer?

Determines the path, multiplexing and management of sessions.

Q38. What Is The Use Of Ddr On Cisco Routers?

It is used for dial on demand routing. DDR provides routing for low volume and periodic traffic.

Q39. What Is Windowing?

It is a kind of flow control.

Q40. What Is The Default Serial Encapsulation?

HDLC is the default serial encapsulation.

Q41. Which Are The Different Forms Of Wan Services Accessed By Cisco Routers?

These are Switched services, Using protocols connecting peer to peer devices and Interface front end to IBM Enterprise Data center computers.

Q42. Which Protocol Helps Test The Connectivity Without Configuration Of Layer 3 Protocols?

CDP protocol

Q43. What Is The Use Of Ipx Sap?

It stands for Service Advertising Protocol and it is used to advertise services.

Q44. List Three Important Properties Of Igrp?

It is a composite metric. There are updates every 60 seconds and it is a poison reverse.

Q45. What Happens If We Set A Wildcard Mask Bit To 0 In Cisco Routers?

The router checks the corresponding bit value.

Q46. Which Hardware Component Is Used To Store Backup Configuration?

NVRAM is used for this.

Q47. Where Can The Backup Configuration File Be Found?

It is stored in the NVRAM.

Q48. Which Hardware Is Necessary For Broadcasts?

switch, repeater and bridge.

Q49. What Are The Three Features Of Ip Access Lists?

There are three different kinds of access lists. These are standard, extended and named.

Q50. Which Switching Method Is Used To Examine The Destination Mac Address?

Cut through is the switching method used to examine it.