Interview Questions.

Network Engineer Interview Questions And Answers


Network Engineer Interview Questions And Answers

Q1. What is a ‘link’?

Ans: A link refers to the connectivity between two devices. It consists of the sort of cables and protocols used in order for one tool with a purpose to talk with the opposite.

Q2. What is a ‘spine network’?

Ans: A spine community is a centralised infrastructure that is designed to distribute distinct routes and facts to diverse networks. It also handles management of bandwidth and diverse channels.

Q3. What is DNS? Why is it used?

Ans: DNS (Domain Name System) is a valuable part of the Internet, supplying a way to healthy names (a website you’re seeking) to numbers (the address for the website).

Q4. What is a LAN?

Ans: A LAN (Local Area Network) and refers to the connection among computers and other network gadgets which can be located within a small bodily location.

Q5. What is a WAN?

Ans: A extensive area network (WAN) is a telecommunications network or laptop community that extends over a huge geographical distance.

Q6. What is ‘network topology’?

Ans: Network topology refers to the layout of a laptop community. It suggests how gadgets and cables are bodily laid out, as well as how they connect to one another.

Q7. What is a router? What are its fundamental roles?

Ans: A router is a layer three community device used to establish verbal exchange between specific networks. The roles of a router are –


Best direction selection

Packet forwarding

Packet filtering

Q8. What are the forms of LAN cables used?

Ans: There are  forms of LAN cables used – ‘Cat 5’ and ‘Cat 6.’ Cat five can guide 100Mbps of speed whilst Cat 6 can guide 1Gbps of velocity

Q9. What is a ‘move table’?

Ans: This is a form of connection among same styles of devices with out using a hub/switch so they can talk.

Q10. What is factor to point hyperlink?

Ans: It refers to an immediate connection between two computers on a network. A point to point connection does no longer want another network gadgets apart from connecting a cable to the NIC cards of each computers.

Q11. What is subnet mask?

Ans: A subnet masks is combined with an IP address a good way to become aware of two components: the extended network address and the host deal with. Like an IP cope with, a subnet masks is made of 32 bits.

Q12. A gateway works wherein layer of the OSI version?

Ans: Transport layer.

Q13. How many layers are there in the OSI reference version? Name them

Ans: There are 7 layers: bodily layer, information link layer, network layer, shipping layer, session layer, presentation layer, and alertness layer.

Q14. Differentiate among ‘ahead lookup’ and ‘reverse lookup’ in DNS?

Ans: Converting names to IP addresses is called ahead research.

Resolving IP addresses to names is referred to as reverse research.

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Q15. What is RIP?

Ans: RIP (Routing Information Protocol) is used by routers to send records from one network to every other.

Q16. What are ‘firewalls’?

Ans: Firewalls serve to defend an inner network from external assaults

Q17. What are the standards for the fine direction selection of a router?

Ans: The following parameters outline the direction choice:

Longest prefix match

Minimum AD (administrative distance)

Lowest metric value

Q18. Define ‘anonymous FTP’.

Ans: Anonymous FTP is a manner of granting a user get entry to to documents in public servers.

Q19. What is the distinction between ‘trendy’ and ‘extended’ ACL (get admission to manipulate listing)?

Ans: Standard ACLs are supply-primarily based, while extended ACLs are source- and destination-based totally.

Q20. What is RAS?

Ans: RAS (Remote Access Services) refers to any mixture of hardware and software program to enable remote access to equipment or records that commonly live on a network of IT devices.

Q21. What is NIC?

Ans: NIC (Network Interface Card) is a peripheral card this is attached to a PC with a purpose to connect with a community. Every NIC has its own MAC deal with that identifies the PC on the community

Q22. How many layers are there under TCP/IP?

Ans: There are four layers: the Network Layer, Internet Layer, Transport Layer and Application Layer.

Q23. What are unique ways of securing a laptop network?

Ans: There are numerous approaches to do this. Install dependable and updated anti-virus program on all computer systems. Make positive firewalls are setup and configured nicely. User authentication will also help plenty. All of these blended could make a tremendously secured community.

Q24. What does 10Base-T suggest?

Ans: The 10 refers back to the statistics transfer price, in this situation is 10Mbps. The phrase Base refers to base band, as oppose to broad band. T method twisted pair, that's the cable used for that community.

Q25. What is the maximum duration allowed for a UTP cable?

Ans: A unmarried phase of UTP cable has an allowable period of 90 to one hundred meters. This quandary can be triumph over with the aid of the usage of repeaters and switches.

Q26. What is records encapsulation?

Ans: Data encapsulation is the manner of breaking down records into smaller attainable chunks before it's far transmitted across the network. It is also in this technique that the supply and destination addresses are connected into the headers, along with parity assessments.

Q27. Describe Network Topology

Ans: Network Topology refers back to the format of a laptop network. It suggests how devices and cables are bodily laid out, in addition to how they connect to one another.

Q28. What is VPN?

Ans: VPN manner Virtual Private Network, a generation that allows a secure tunnel to be created across a network consisting of the Internet. For example, VPNs assist you to establish a at ease dial-up connection to a far flung server.

Q29. Briefly describe NAT.

Ans: NAT is Network Address Translation. This is a protocol that gives a way for multiple computer systems on a commonplace network to share unmarried connection to the Internet.

Q30. What is a personal IP deal with?

Ans: Private IP addresses are assigned for use on intranets. These addresses are used for internal networks and aren't routable on external public networks. These ensures that no conflicts are gift among inner networks at the same time as at the same time the equal variety of personal IP addresses are reusable for multiple intranets due to the fact that they do not “see” every different.

Q31.  What is the principle cause of OSPF?

Ans: OSPF, or Open Shortest Path First, is a link-country routing protocol that makes use of routing tables to determine the great feasible direction for facts alternate.

Q32. What is NOS?

Ans: NOS, or Network Operating System, is specialized software program whose predominant mission is to provide community connectivity to a pc so as for it with a purpose to speak with different computers and connected devices.

Q33. What is tracert?

Ans: Tracert is a Windows software application which could used to trace the route taken by information from the router to the vacation spot community. It additionally suggests the quantity of hops taken at some point of the entire transmission direction.

Q34. What is Hybrid Network?

Ans: A hybrid network is a network setup that uses both customer-server and peer-to-peer architecture.

Q35. What is DoS?

Ans: DoS, or Denial-of-Service attack, is an try to save you customers from being able to get right of entry to the internet or some other network offerings. Such assaults may additionally are available exclusive paperwork and are done through a group of perpetuators. One common approach of doing this is to overload the device server so it can't anymore method legitimate visitors and will be compelled to reset.

Q36. What is the motive of cables being shielded and having twisted pairs?

Ans: The predominant motive of that is to save you crosstalk. Crosstalks are electromagnetic interferences or noise which can affect data being transmitted across cables.

Q37. What is the gain of address sharing?

Ans: By using deal with translation in place of routing, address sharing gives an inherent security advantage. That’s because host PCs at the Internet can most effective see the general public IP cope with of the external interface at the computer that offers address translation and no longer the personal IP addresses at the internal community.

Q38. What are MAC addresses?

Ans: MAC, or Media Access Control, uniquely identifies a tool on the community. It is also known as bodily deal with or Ethernet cope with. A MAC cope with is made up of 6-byte components.

Q39. How can you perceive the IP elegance of a given IP deal with?

Ans: By looking at the primary octet of any given IP address, you may identify whether or not it’s Class A, B or C. If the first octet starts with a zero bit, that deal with is Class A. If it begins with bits 10 then that deal with is a Class B address. If it starts offevolved with 110, then it’s a Class C network.

Q40. What do mean with the aid of tunnel mode?

Ans: This is a method of records trade wherein  communicating computer systems do not use IPSec themselves. Instead, the gateway this is connecting their LANs to the transit community creates a virtual tunnel that uses the IPSec protocol to at ease all communication that passes via it.

Q41. What is DHCP?

Ans: DHCP is short for Dynamic Host Configuration Protocol. Its most important task is to robotically assign an IP deal with to devices across the community. It first tests for the next to be had cope with no longer yet taken through any device, then assigns this to a community device.

Q42. What benefits does fiber optics have over other media?

Ans: One main gain of fiber optics is that is it much less susceptible to electric interference. It also supports better bandwidth, which means greater information can be transmitted and obtained. Signal degrading is also very minimum over long distances.

Q43. What is ipconfig?

Ans: Ipconfig is a software program this is commonly used to become aware of the addresses facts of a computer on a network. It can show the physical address as well as the IP cope with.

Q44. Describe Ethernet.

Ans: Ethernet is one of the famous networking technologies used in recent times. It become evolved for the duration of the early 1970s and is primarily based on specs as stated within the IEEE. Ethernet is utilized in nearby region networks.

Q45.  What are a few drawbacks of implementing a hoop topology

Ans: In case one notebook on the community suffers a malfunction, it is able to deliver down the entire community. Another disadvantage is that when there are changes and reconfigurations needed to be done on a selected a part of the community, the entire network must be briefly introduced down as nicely.

Q46. How does dynamic host configuration protocol aid in community administration?

Ans: Instead of getting to go to each consumer laptop to configure a static IP address, the network administrator can observe dynamic host configuration protocol to create a pool of IP addresses called scopes that may be dynamically assigned to customers.

Q47. What is sneakernet?

Ans: Sneakernet is thought to be the earliest shape of networking in which facts is bodily transported the use of removable media, inclusive of disk, tapes.

Q48. When you pass the NIC cards from one PC to any other PC, does the MAC deal with gets transferred as well?

Ans: Yes, that’s because MAC addresses are hard-wired into the NIC circuitry, no longer the PC. This also means that a PC could have a one-of-a-kind MAC address while the NIC card turned into replace with the aid of some other one.

Q49. What is the significance of Encryption on a community?

Ans: Encryption is the manner of translating records into a code that is unreadable by the person. It is then translated returned or decrypted again to its normal readable layout the use of a secret key or password. Encryption help make certain that facts this is intercepted midway might remain unreadable because the user has to have the proper password or key for it.

Q50. What is the difference among CSMA/CD and CSMA/CA?

Ans: CSMA/CD, or Collision Detect, retransmits statistics frames whenever a collision happened. CSMA/CA, or Collision Avoidance, will first broadcast rationale to send previous to records transmission.