Interview Questions.

Question 1. Why Does Active Ftp Not Work With Network Firewalls?

Answer :

When a person initiates a reference to the FTP server,  TCP connections are set up. The second TCP connection (FTP facts connection) is initiated and established from the FTP server. When a firewall is among the FTP patron and server, the firewall would block the relationship initiated from the FTP server because it is a connection initiated from outdoor. To resolve this, Passive FTP can be used or the firewall rule can be changed to add the FTP server as depended on.

Question 2. Which Feature On A Network Switch Can Be Used To Prevent Rogue Dhcp Servers?

Answer :

DHCP Snooping.

Networking Interview Questions
Question three. Which Feature On A Cisco Ios Firewall Can Be Used To Block Incoming Traffic On A Ftp Server?

Answer :Extended ACL.

Question 4. Name One Secure Network Protocol Which Can Be Used Instead Of Telnet To Manage A Router?

Answer :

SSH.

Networking Tutorial
Question five. Provide A Reason As To Why Https Should Be Used Instead Of Http?

Answer :

HTTP sends statistics in clean textual content whereas HTTPS sends facts encrypted.

Computer Science Engineering Interview Questions
Question 6. How Can You Prevent A Brute Force Attack On A Windows Login Page?

Answer :

Setup a account lockout for specific range of tries, in order that the consumer account might be locked up mechanically after the specified range.

Question 7. In An Icmp Address Mask Request, What Is The Attacker Looking For?

Answer :

The attacker is seeking out the subnet/network masks of the victim. This could assist the attacker to map the inner community.

Network Security Tutorial Computer Hardware Interview Questions
Question eight. Why Is Rip V1 Insecure In A Network?

Answer :

RIP v1 does not use a password for authentication as with Rip v2. This makes it viable to attackers to send rogue RIP packets and corrupt the routing desk.

Question 9. Which Feature On A Network Switch Can Be Used To Protect Against Cam Flooding Attacks?

Answer :

Port-Security characteristic may be used for the identical. In a cam flooding assault, the attacker sends a storm of mac-addresses (frames) with specific values. The aim of the attacker is to replenish the cam desk. Port-Security may be used to restrict the range of mac-addresses allowed on the port.

Network Security Interview Questions
Question 10. Which Protocol Does Https Uses At The Transport Layer For Sending And Receiving Data?

Answer :

TCP.

Computer Security Tutorial
Question eleven. What Are 10base2, 10base5 And 10baset Ethernet Lans ?

Answer :

10Base2: An Ethernet term meaning a maximum switch rate of 10 Megabits in keeping with second that makes use of baseband signaling, with a contiguous cable segment length of 100 meters and a most of two segments.

10Base5: An Ethernet term which means a maximum transfer fee of 10 Megabits consistent with second that uses baseband signaling, with 5 continuous segments not exceeding one hundred meters in line with segment.

10BaseT: An Ethernet time period that means a most transfer rate of 10 Megabits consistent with second that makes use of baseband signaling and twisted pair cabling.

Hardware and Networking Interview Questions
Question 12. What Is The Difference Between An Unspecified Passive Open And A Fully Specified Passive Open ?

Answer :

An unspecified passive open has the server looking ahead to a connection request from a patron. A absolutely certain passive open has the server awaiting a connection from a selected patron.

Networking Interview Questions
Question 13. Explain The Function Of Transmission Control Block ?

Answer :

A TCB is a complex information shape that incorporates a large amount of records about each connection.

Computer Logical Organization Tutorial
Question 14. What Is A Management Information Base (mib) ?

Answer :

A Management Information Base is a part of each SNMP-managed tool. Each SNMP agent has the MIB database that consists of information about the tool’s fame, its performance, connections, and configuration. The MIB is queried by means of SNMP.

Question 15. What Is Anonymous Ftp And Why Would You Use It

Answer :

Anonymous FTP permits users to connect to a bunch without the use of a valid login and password. Usually, anonymous FTP uses a login known as anonymous or visitor, with the password generally requesting the person’s ID for monitoring purposes best. Anonymous FTP is used to allow a huge variety of users to get right of entry to files at the host while not having to visit the trouble of putting in logins for all of them. Anonymous FTP structures typically have strict controls over the areas an anonymous person can get right of entry to.

Computer architecture Interview Questions
Question sixteen. What Is A Pseudo Tty ?

Answer :

A pseudo tty or fake terminal permits external machines to connect thru Telnet or rlogin. Without a pseudo tty, no connection can take region.

Question 17. What Is Rex ?

Answer :

What advantage does REX offer different comparable utilities

PRTG Interview Questions
Question 18. What Does The Mount Protocol Do ?

Answer :

The Mount protocol returns a report handle and the call of the report system in which a requested document is living. The message is sent to the consumer from the server after reception of a patron’s request.

Computer Science Engineering Interview Questions
Question 19. What Is External Data Representation ?

Answer :

External Data Representation is a way of encoding records inside an RPC message, used to ensure that the statistics is not device-structured.

Question 20. Bootp Helps A Diskiess Workstation Boot. How Does It Get A Message To The Network Looking For Its Lp Address And The Location Of Its Operating System Boot Files ?

Answer :

BQOTP sends a UDP message with a subnetwork broadcast deal with and waits for a respond from a server that gives it the IP cope with. The equal message may include the name of the device that has the boot files on it. If the boot photo place is not particular, the notebook sends another UDP message to query the server.

Computer Security Interview Questions
Question 21. What Is A Dns Resource Record ?

Answer :

A useful resource document is an entry in a name server’s database. There are several types of aid facts used, which include name-to-address resolution data. Resource information are maintained as ASCII documents.

Question 22. What Protocol Is Used By Dns Name Servers ?

Answer :

DNS uses UDP for communication between servers, It is a better desire than TCP due to the advanced velocity a connectionless protocol gives. Of direction, transmission reliability suffers with UDP.

Question 23. What Is The Difference Between Interior And Exterior Neighbor Gateways ?

Answer :

Interior gateways join LANs of 1 agency, while outside gateways connect the business enterprise to the outdoor international.

Computer Systems Analyst Interview Questions
Question 24. What Is The Hello Protocol Used For ?

Answer :

The HELLO protocol makes use of time in place of distance to decide gold standard routing. It is an alternative to the Routing Information Protocol.

Computer Hardware Interview Questions
Question 25. What Are The Advantages And Disadvantages Of The Three Types Of Routing Tables ?

Answer :

The 3 sorts of routing tables are fixed, dynamic, and fixed primary. The fixed table should be manually modified each time there is a change. A dynamic table modifications its information primarily based on community site visitors, reducing the amount of manual preservation. A constant critical table we could a supervisor regulate simplest one table, that is then examine through different devices. The fixed principal table reduces the want to update every gadget’s desk, as with the fixed table. Usually a dynamic table reasons the fewest issues for a network administrator, despite the fact that the table’s contents can change without the administrator being aware of the change.

Question 26. What Is Source Route ?

Answer :

It is a chain of lP addresses identifying the path a datagram need to observe. A supply path may additionally optionally be protected in an IP datagram header.

Question 27. What Is Rip (routing Information Protocol) ?

Answer :

It is a easy protocol used to change information among the routers.

Network Security Interview Questions
Question 28. What Is Slip (serial Line Interface Protocol) ?

Answer :

It is a totally easy protocol used for transmission of IP datagrams throughout a serial line.

Question 29. What Is Proxy Arp ?

Answer :

It is the usage of a router to reply ARP requests. This may be achieved while the originating host believes that a destination is neighborhood, whilst in reality is lies beyond router.

Question 30. What Is Ospf ?

Answer :

It is an Internet routing protocol that scales properly, can course site visitors alongside a couple of paths, and uses information of an Internet’s topology to make correct routing choices.

Question 31. What Is Kerberos ?

Answer :

It is an authentication carrier developed at the Massachusetts Institute of Technology. Kerberos makes use of encryption to prevent intruders from discovering passwords and gaining unauthorized access to files.

Question 32. What Is A Multi-homed Host ?

Answer :

It is a host that has a multiple network interfaces and that calls for multiple IP addresses is known as as a Multi-homed Host.

Question 33. What Is Nvt (community Virtual Terminal) ?

Answer :

It is a set of regulations defining a very simple digital terminal interplay. The NVT is used within the start of a Telnet session.

Hardware and Networking Interview Questions
Question 34. What Is Gateway-to-gateway Protocol ?

Answer :

It is a protocol formerly used to change routing statistics between Internet core routers.

Question 35. What Is Bgp (border Gateway Protocol) ?

Answer :

It is a protocol used to advertise the set of networks that may be reached with in an independent device. BGP permits this statistics to be shared with the self sustaining machine. This is more recent than EGP (Exterior Gateway Protocol).

Question 36. What Is Autonomous System ?

Answer :

It is a set of routers under the manipulate of a unmarried administrative authority and that makes use of a not unusual Interior Gateway Protocol.

Computer structure Interview Questions
Question 37. What Is Egp (exterior Gateway Protocol) ?

Answer :

It is the protocol the routers in neighboring autonomous structures use to identify the set of networks that may be reached within or thru every self reliant device.

Question 38. What Is Igp (interior Gateway Protocol) ?

Answer :

It is any routing protocol used within an self sustaining gadget.

Question 39. What Is Mail Gateway ?

Answer :

It is a machine that performs a protocol translation among distinctive e-mail delivery protocols.

Question 40. What Is Wide-mouth Frog ?

Answer :

Wide-mouth frog is the most effective known key distribution middle (KDC) authentication protocol.

PRTG Interview Questions
Question 41. What Are Dig Rams And Trig Rams ?

Answer :

The maximum commonplace  letter combos are known as as digrams. E.G. Th, in, er, re and an. The maximum common three letter mixtures are called as trigrams. E.G. The, ing, and, and ion.

Question 42. What Is Silly Window Syndrome ?

Answer :

It is a trouble which could smash TCP overall performance. This problem takes place when statistics are passed to the sending TCP entity in huge blocks, but an interactive application at the receiving facet reads 1 byte at a time.

Computer Security Interview Questions
Question forty three. What Is Region ?

Answer :

When hierarchical routing is used, the routers are divided into what we call areas, with every router knowing all the information about the way to path packets to locations inside its personal area, however understanding nothing about the inner structure of different regions.

Question forty four. What Is Multicast Routing ?

Answer :

Sending a message to a collection is called multicasting, and its routing algorithm is referred to as multicast routing.

Question forty five. What Is Traffic Shaping ?

Answer :

One of the primary causes of congestion is that site visitors is regularly busy. If hosts might be made to transmit at a uniform rate, congestion could be less commonplace. Another open loop method to help manipulate congestion is forcing the packet to be transmitted at a extra predictable charge. This is known as site visitors shaping.

Question 46. What Is Packet Filter ?

Answer :

Packet filter is a wellknown router ready with some more functionality. The more capability lets in each incoming or outgoing packet to be inspected. Packets assembly some criterion are forwarded commonly. Those that fail the take a look at are dropped.

Question forty seven. What Is Virtual Path ?

Answer :

Along any transmission route from a given supply to a given destination, a collection of digital circuits can be grouped together into what is referred to as path.

Question forty eight. What Is Virtual Channel ?

Answer :

Virtual channel is commonly a connection from one source to 1 vacation spot, despite the fact that multicast connections also are accepted. The other name for virtual channel is digital circuit.

Question forty nine. What Is Logical Link Control ?

Answer :

One of two sublayers of the information hyperlink layer of OSI reference model, as defined by means of the IEEE 802 popular. This sublayer is accountable for preserving the hyperlink among computers when they are sending facts across the bodily network connection.

Question 50. Why Should You Care About The Osi Reference Model ?

Answer :

It provides a framework for discussing network operations and design.

Question 51. What Is The Difference Between Routable And Non- Routable Protocols ?

Answer :

Routable protocols can paintings with a router and may be used to build massive networks. Non-Routable protocols are designed to work on small, nearby networks and cannot be used with a router

Question fifty two. What Is Mau ?

Answer :

In token Ring , hub is called Multistation Access Unit(MAU).

Question fifty three. Explain 5-4-3 Rule ?

Answer :

In a Ethernet network, among any two factors on the network, there may be no more than five community segments or four repeaters, and of these 5 segments best 3 of segments may be populated.

Question fifty four. What Is The Difference Between Tftp And Ftp Application Layer Protocols ?

Answer :

The Trivial File Transfer Protocol (TFTP) allows a nearby host to acquire files from a remote host but does not provide reliability or security. It makes use of the essential packet delivery services presented by means of UDP.

The File Transfer Protocol (FTP) is the usual mechanism supplied by way of TCP / IP for copying a record from one host to every other. It makes use of the services provided with the aid of TCP and so is reliable and secure. It establishes two connections (virtual circuits) between the hosts, one for records switch and another for manipulate facts.

Question fifty five. What Is The Range Of Addresses In The Classes Of Internet Addresses ?

Answer :

Class A 0.0.0.0 - 127.255.255.255
Class B 128.Zero.0.Zero - 191 .255.255.255
Class C 192.Zero.Zero.0 - 223.255.255.255
Class D 224.Zero.Zero.Zero - 239.255.255.255
Class E 240.Zero.Zero.0 - 247.255.255.255

Question fifty six. What Is The Minimum And Maximum Length Of The Header In The Tcp Segment And Lp Datagram?

Answer :

The header have to have a minimum duration of 20 bytes and may have a maximum period of 60 bytes.

Question fifty seven. What Is Difference Between Arp And Rarp ?

Answer :

The deal with resolution protocol (ARP) is used to accomplice the 32 bit lP deal with with the 48 bit bodily deal with, used by a host or a router to find the physical cope with of every other host on its community through sending a ARP query packet that consists of the IP deal with of the receiver.

The opposite cope with decision protocol (RARP) lets in a bunch to discover its Internet deal with when it is aware of best its physical cope with.

Question fifty eight. What Is Icmp ?

Answer :

ICMP is Internet Control Message Protocol, a network layer protocol of the TCP/IP suite used by hosts and gateways to ship notification of datagram troubles returned to the sender. It makes use of the echo test / reply to test whether a destination is accessible and responding. It also handles each manipulate and error messages.

Question fifty nine. What Are The Data Units At Different Layers Of The Tcp / Ip Protocol Suite ?

Answer :

The records unit created at the utility layer is known as a message, on the transport layer the facts unit created is known as either a segment or an consumer datagram, on the network layer the statistics unit created is referred to as the datagram, on the information link layer the datagram is encapsulated in to a body and finally transmitted as alerts alongside the transmission media.

Question 60. What Is Bandwidth

Answer :

Every line has an top limit and a lower limit on the frequency of signals it may deliver. This confined range is known as the bandwidth.

Question sixty one. Difference Between Bit Rate And Baud Rate?

Answer :

Bit price is the wide variety of bits transmitted at some stage in one 2nd while baud price refers back to the number of signal devices in line with 2nd which are required to represent the ones bits.

Baud rate = bit price / N
in which N is not any-of-bits represented by means of each sign shift.

Question 62. What Is Mac Address ?

Answer :

The address for a device as it's miles identified at the Media Access Control (MAC) layer in the network architecture. MAC address is usually stored in ROM on the network adapter card and is specific.

Question sixty three. What Is Attenuation ?

Answer :

The degeneration of a signal over distance on a network cable is known as attenuation.

Question sixty four. What Is Cladding ?

Answer :

A layer of a tumbler surrounding the middle fiber of glass internal a fiber-optic cable.

Question sixty five. What Is Raid ?

Answer :

A technique for presenting fault tolerance by the usage of a couple of tough disk drives.

Question sixty six. What Is Netbios And Netbeui ?

Answer :

NETBIOS is a programming interface that permits I/O requests to be sent to and received from a faraway laptop and it hides the networking hardware from programs.

NETBEUI is NetBIOS extended consumer interface. A delivery protocol designed by microsoft and IBM for the use on small subnets.

Question sixty seven. What Is Redirector ?

Answer :

Redirector is software program that intercepts record or prints I/O requests and interprets them into community requests. This comes under presentation layer.

Question sixty eight. What Is Beaconing ?

Answer :

The method that lets in a community to self-restore networks problems. The stations on the network notify the other stations at the ring while they're not receiving the transmissions. Beaconing is utilized in Token ring and FDDI networks.

Question sixty nine. What Is Terminal Emulation, In Which Layer It Comes

Answer :

Telnet is also called as terminal emulation. It belongs to utility layer.

Question 70. What Is Frame Relay, In Which Layer It Comes

Answer :

Frame relay is a packet switching technology. It will operate in the data link layer.

Question 71. What Do You Meant By "triple X" In Networks ?

Answer :

The function of PAD (Packet Assembler Disassembler) is defined in a document called X.3. The general protocol has been defined between the terminal and the PAD, called X.28; any other popular protocol exists between hte PAD and the network, known as X.29. Together, these three recommendations are frequently known as “triple X”

Question seventy two. What Is Sap ?

Answer :

Series of interface points that permit other computer systems to speak with the other layers of network protocol stack.

Question 73. What Is Subnet ?

Answer :

A widespread time period for segment of a huge networks generally separated by way of a bridge or router.

Question seventy four. What Is Brouter ?

Answer :

Hybrid devices that integrate the functions of each bridges and routers.

Question seventy five. How Gateway Is Different From Routers ?

Answer :

A gateway operates on the top levels of the OSI model and interprets records between two absolutely specific network architectures or information formats.

Question seventy six. What Are The Different Type Of Networking / Internetworking Devices ?

Answer :

Repeater: Also known as a regenerator, it's miles an electronic tool that operates only at physical layer. It receives the sign in the network earlier than it becomes vulnerable, regenerates the original bit sample and puts the refreshed reproduction back in to the hyperlink.

Bridges: These function both in the bodily and statistics hyperlink layers of LANs of equal kind. They divide a larger community in to smaller segments. They comprise good judgment that permit them to maintain the site visitors for every section separate and for this reason are repeaters that relay a frame simplest the facet of the segment containing the meant recipient and manage congestion.

Routers: They relay packets amongst multiple interconnected networks (i.E. LANs of various kind). They function inside the physical, records link and community layers. They incorporate software that allow them to decide which of the numerous viable paths is the great for a particular transmission.

Gateways: They relay packets amongst networks which have exceptional protocols (e.G. Among a LAN and a WAN). They take delivery of a packet formatted for one protocol and convert it to a packet formatted for any other protocol earlier than forwarding it. They perform in all seven layers of the OSI model.

Question seventy seven. What Is Mesh Network ?

Answer :

A community wherein there are multiple network hyperlinks between computer systems to offer more than one paths for statistics to journey.

Question 78. What Is Passive Topology ?

Answer :

When the computer systems at the community truly pay attention and get hold of the sign, they're known as passive because they don’t expand the sign in any manner. Example for passive topology - linear bus.

Question seventy nine. What Are The Important Topologies For Networks ?

Answer :

BUS topology: In this each pc is at once linked to primary network cable in a unmarried line.
Advantages: Inexpensive, easy to install, easy to apprehend, easy to extend.

STAR topology: In this all computer systems are related using a critical hub.
Advantages: Can be inexpensive, easy to put in and reconfigure and smooth to problem shoot physical issues.

RING topology: In this all computer systems are linked in loop.
Advantages: All computer systems have same get entry to to network media, set up may be easy, and signal does now not degrade as a lot as in other topologies because each laptop regenerates it.

Question eighty. What Are Major Types Of Networks And Explain ?

Answer :

Server-based totally community
Peer-to-peer network
Peer-to-peer network, computers can act as each servers sharing sources and as customers using the resources.
Server-based totally networks provide centralized manage of community sources and depend upon server computers to provide security and community management.
Question 81. What Is Protocol Data Unit ?

Answer :

The facts unit inside the LLC degree is known as the protocol records unit (PD U). The PDU consists of of 4 fields a vacation spot service get entry to point (DSAP), a source service get right of entry to factor (SSAP), a manipulate area and an information area. DSAP, SSAP are addresses utilized by the LLC to identify the protocol stacks at the receiving and sending machines which can be producing and using the facts. The manage field specifies whether the PDU body is a facts body (I - body) or a supervisory body (S - body) or a unnumbered frame (U - frame).

Question 82. What Is Difference Between Baseband And Broadband Transmission ?

Answer :

In a base band transmission, the whole bandwidth of the cable is ate up with the aid of a unmarried signal. In broadband transmission, indicators are sent on multiple frequencies, permitting multiple indicators to be despatched simultaneously.

Question 83. What Are The Possible Ways Of Data Exchange ?

Answer :

Simplex
Half-duplex
Full-duplex.
Question eighty four. What Are The Types Of Transmission Media ?

Answer :

Signals are usually transmitted over some transmission media which might be broadly categorised in to 2 classes.

Guided Media: These are people who provide a conduit from one tool to some other that encompass twisted-pair, coaxial cable and fiber-optic cable. A signal journeying alongside any of these media is directed and is contained by the physical limits of the medium. Twisted-pair and coaxial cable use steel that accept and shipping alerts inside the form of electrical current. Optical fiber is a tumbler or plastic cable that accepts and transports signals within the shape of light.

Unguided Media: This is the wi-fi media that shipping electromagnetic waves with out using a physical conductor. Signals are broadcast either through air. This is completed via radio communication, satellite communication and cell telephony.

Question eighty five. What Is Point-to-point Protocol ?

Answer :

A communications protocol used to connect computer systems to faraway networking services which includes Internet provider providers.

Question 86. What Are The Two Types Of Transmission Technology Available ?

Answer :

Broadcast and
factor-to-point
Question 87. Difference Between The Communication And Transmission?

Answer :

Transmission is a bodily movement of information and situation troubles like bit polarity, synchronization, clock etc. Communication approach the meaning complete change of facts among  communique media.