{
"iq":[{"id":"1",
"q":"What is Network?",
"answer":"A network is a set of devices connected by physical media links.A network is recursively is a connection of two or more nodes by a physical link or two or more networks connected by one or more nodes. "
},
{"id":"2",
"q":"What is a Link? ",
"answer":"A link refers to the connectivity between two devices.It includes the type of cables and protocols used in order for one device to be able to communicate with the other. "
},
{"id":"3",
"q":"What is a node?",
"answer":"A network can consist of two or more computers directly connected by some physical medium such as coaxial cable or optical fiber.Such a physical medium is called as Links and the computer it connects is called as Nodes."
},
{"id":"4",
"q":"What is a gateway or Router?",
"answer":"A node that is connected to two or more networks is commonly called as router or Gateway.It generally forwards message from one network to another. "
},
{"id":"5",
"q":"What is point-point link? ",
"answer":"If the physical links are limited to a pair of nodes it is said to be point-point link."
},
{"id":"6",
"q":"What is Multiple Access? ",
"answer":"If the physical links are shared by more than two nodes, it is said to be Multiple Access. "
},
{"id":"7",
"q":"What is a gateway or Router?",
"answer":"A node that is connected to two or more networks is commonly called as router or Gateway. It generally forwards message from one network to another."
},
{"id":"8",
"q":"What are the advantages of Distributed Processing?",
"answer":"Security/Encapsulation\n\nDistributed database\n\nFaster Problem solving\n\nSecurity through redundancy\n\nCollaborative Processing"
},
{"id":"9",
"q":"What is backbone network?",
"answer":"A backbone network is a centralized infrastructure that is designed to distribute different routes and data to various networks. It also handles management of bandwidth and various channels."
},
{"id":"10",
"q":" What is a LAN?",
"answer":"LAN is short for Local Area Network. It refers to the connection between computers and other network devices that are located within a small physical location."
},
{"id":"11",
"q":"What is anonymous FTP?",
"answer":"Anonymous FTP is a way of granting user access to files in public servers. Users that are allowed access to data in these servers do not need to identify themselves, but instead log in as an anonymous guest."
},
{"id":"12",
"q":"What is subnet mask?",
"answer":"A subnet mask is combined with an IP address in order to identify two parts:the extended network address and the host address. Like an IP address, a subnet mask is made up of 32 bits."
},
{"id":"13",
"q":"What is the maximum length allowed for a UTP cable?",
"answer":"A single segment of UTP cable has an allowable length of 90 to 100 meters. This limitation can be overcome by using repeaters and switches."
},
{"id":"14",
"q":"What is data encapsulation?",
"answer":"Data encapsulation is the process of breaking down information into smaller manageable chunks before it is transmitted across the network. It is also in this process that the source and destination addresses are attached into the headers, along with parity checks."
},
{"id":"15",
"q":" Describe Network Topology?",
"answer":" Network Topology refers to the layout of a computer network.It shows how devices and cables are physically laid out, as well as how they connect to one another. "
},
{"id":"16",
"q":"Define Routing?",
"answer":"The process of determining systematically hoe to forward messages toward the destination nodes based on its address is called routing."
},
{"id":"17",
"q":"What is semantic gap?",
"answer":"Defining a useful channel involves both understanding the applications requirements and recognizing the limitations of the underlying technology. The gap between what applications expects and what the underlying technology can provide is called semantic gap. "
},
{"id":"18",
"q":"What is Round Trip Time?",
"answer":"The duration of time it takes to send a message from one end of a network to the other and back, is called RTT."
},
{"id":"19",
"q":"Describe Domain Name System.?",
"answer":"There are two types of client/server programs.First is used directly by the user, such as e-mail, Second supports other application programs. The Domain Name System (DNS) is a supporting program that is used by other programs such as to find the IP address of an e-mail recipient."
},
{"id":"20",
"q":"Describe Hierarchical Namespace.?",
"answer":"In a hierarchical name space, each name is combination of several parts as:\n\nType of the organization.\n\nName of an organization.\n\nDepartments in the organization.\n\nA central authority can assign the part of the name that defines the nature and name of the organization. The other things of the name the organization provides itself. The organization can add suffixes (or prefixes) to the name to define its host.\n\nThe company need not worry about the prefix if it is same as that of another organization because, even if part of an address is the same, the whole address is different."
},
{"id":"21",
"q":"What is the POP3 protocol.?",
"answer":"Post Office Protocol, version 3 is used for accessing the message. POP3 is very simple protocol and has limited functionality. POP has different version but currently version 3 is used. A POP3 server listens on well-known port 110. POP3 supports two types of mode.\n\nDelete Mode: In this mode, the mail is deleted from the mailbox after each retrieval.\n\nKeep Mode. The mail remains in the mailbox after retrieval. "
},
{"id":"22",
"q":"What is Anonymous FTP?",
"answer":"Some sites provide the functionality that user can access the file with limited access. To access these files, a user does not need to have an account or password. For using FTP, the user enters \"anonymous\" as a user ID and guest as password. Usually, you can enter anything as a password. "
},
{"id":"23",
"q":"What is User Agent?",
"answer":"User agent is a software that provides the service to the user to make the process of sending and receiving a message easier. The following are User Agent services."
},{"id":"24",
"q":" what is Channelization in networks.? ",
"answer":"Channelization is a multiple-access method in which the available bandwidth of a link is shared in time, frequency, or through code, between different stations.There are three basic approaches to achieve channelization."
},{"id":"25",
"q":"Differentiate between hub and switch.?",
"answer":"Hub is a layer 1 device while Switch is layer 2 device.Hub works on single collision and single broadcast domain while switch works on per port collision and single broadcast domain."
},{"id":"26",
"q":"What is peer to peer?",
"answer":"Peer to peer are networks that does not reply on a server.All PCs on this network act as individual workstations."
},{"id":"27",
"q":"What is ICMP?",
"answer":"ICMP is Internet Control Message Protocol. It provides messaging and communication for protocols within the TCP/IP stack. This is also the protocol that manages error messages that are used by network tools such as PING. "
},{"id":"28",
"q":"What is netstat?",
"answer":"Netstat is a command line utility program.It provides useful information about the current TCP/IP settings of a connection."
},{"id":"29",
"q":"What is the number of network IDs in a Class C network?",
"answer":"For a Class C network, the number of usable Network ID bits is 21.\n\nThe number of possible network IDs is 2 raised to 21 or 2,097,152.\n\nThe number of host IDs per network ID is 2 raised to 8 minus 2, or 254."
},{"id":"30",
"q":" What is DHCP?",
"answer":"DHCP is short for Dynamic Host Configuration Protocol.\n\nIts main task is to automatically assign an IP address to devices across the network.\n\nIt first checks for the next available address not yet taken by any device, then assigns this to a network device."
},{"id":"31",
"q":"What is tracert? ",
"answer":"Tracert is a Windows utility program that can used to trace the route taken by data from the router to the destination network.\n\nIt also shows the number of hops taken during the entire transmission route."
},{"id":"32",
"q":"What are firewalls?",
"answer":"Firewalls serve to protect an internal network from external attacks.These external threats can be hackers who want to steal data or computer viruses that can wipe out data in an instant.It also prevents other users from external networks from gaining access to the private network. "
},{"id":"33",
"q":"What is client/server?",
"answer":"Client/server is a type of network wherein one or more computers act as servers. Servers provide a centralized repository of resources such as printers and files. Clients refers to workstation that access the server. "
},{"id":"34",
"q":" Explain clustering support?",
"answer":"Clustering support refers to the ability of a network operating system to connect multiple servers in a fault-tolerant group. The main purpose of this is the in the event that one server fails, all processing will continue on with the next server in the cluster."
},
{"id":"35",
"q":"What is redirector?",
"answer":" Redirector is software that intercepts file or prints I/O requests and translates them into network requests. This comes under presentation layer. "
},
{"id":"36",
"q":" What is multicast routing?",
"answer":"Multicast routing is a targeted form of broadcasting that sends message to a selected group of user, instead of sending it to all users on a subnet."
},
{"id":"37",
"q":" How are IP addresses arranged and displayed?",
"answer":"IP addresses are displayed as a series of four decimal numbers that are separated by period or dots.Another term for this arrangement is the dotted decimal format.\n\nAn example is 192.168.101.2 "
},{"id":"38",
"q":"What is mesh topology?",
"answer":"Mesh topology is a setup wherein each device is connected directly to every other device on the network.\n\nConsequently, it requires that each device have at least two network connections."
},{"id":"39",
"q":" What is RSA algorithm?",
"answer":"RSA is short for Rivest-Shamir-Adleman algorithm.It is the most commonly used public key encryption algorithm in use today."
},{"id":"40",
"q":"What protocols fall under the TCP/IP Internet Layer?",
"answer":"There are 4 protocols that are being managed by this layer. These are ICMP, IGMP, IP and ARP."
},{"id":"41",
"q":"What is the difference between TFTP and FTP application layer protocols?",
"answer":"The Trivial File Transfer Protocol (TFTP) allows a local host to obtain files from a remote host but does not provide reliability or security.\n\nIt uses the fundamental packet delivery services offered by UDP.\n\nThe File Transfer Protocol (FTP) is the standard mechanism provided by TCP / IP for copying a file from one host to another.\n\nIt uses the services offer by TCP and so is reliable and secure.\n\nIt establishes two connections (virtual circuits) between the hosts,one for data transfer and another for control information."
},{"id":"42",
"q":"What MAU?",
"answer":"In token Ring , hub is called Multi-station Access Unit(MAU)."
},
{"id":"43",
"q":"Why should you care about the OSI Reference Model?·",
"answer":"It provides a framework for discussing network operations and design."
},{"id":"44",
"q":"What is SAP?",
"answer":" Series of interface points that allow other computers to communicate with the other layers of network protocol stack."
},{"id":"45",
"q":"What do you meant by \"triple X\" in Networks?",
"answer":"The function of PAD (Packet Assembler Disassembler) is described in a document known as X.3. The standard protocol has been defined between the terminal and the PAD, called X.28;\n\nanother standard protocol exists between hte PAD and the network, called X.29. Together, these three recommendations are often called \"triple X\"."
},{"id":"46",
"q":"Difference between the communication and transmission.?",
"answer":"Transmission is a physical movement of information and concern issues like bit polarity, synchronisation, clock etc.\n\nCommunication means the meaning full exchange of information between two communication media. "
},{"id":"47",
"q":" What is Beaconing?",
"answer":"The process that allows a network to self-repair networks problems. The stations on the network notify the other stations on the ring when they are not receiving the transmissions. Beaconing is used in Token ring and FDDI networks."
},{"id":"48",
"q":"What is IPv6?",
"answer":"IPv6 , or Internet Protocol version 6, was developed to replace IPv4.\n\nAt present, IPv4 is being used to control internet traffic, butis expected to get saturated in the near future.\n\nIPv6 was designed to overcome this limitation."
},
{"id":"49",
"q":"What is sneakernet? ",
"answer":"Sneakernet is believed to be the earliest form of networking wherein data is physically transported using removable media, such as disk, tapes. "
},{"id":"50",
"q":" What is one advantage of mesh topology?",
"answer":"In the event that one link fails, there will always be another available. Mesh topology is actually one of the most fault-tolerant network topology."
},
{"id":"51",
"q":"What can be done to fix signal attenuation problems?",
"answer":"A common way of dealing with such a problem is to use repeaters and hub,because it will help regenerate the signal and therefore prevent signal loss.Checking if cables are properly terminated is also a must."
},
{"id":"52",
"q":"What is ipconfig?",
"answer":"Ipconfig is a utility program that is commonly used to identify the addresses information of a computer on a network.It can show the physical address as well as the IP address."
},{"id":"53",
"q":"What common software problems can lead to network defects?",
"answer":"Software related problems can be any or a combination of the following:\n\n– client server problems\n\n– application conflicts\n\n– error in configuration\n\n– protocol mismatch\n\n– security issues\n\n– user policy and rights issues "
},{"id":"54",
"q":"What is the use of a default gateway?",
"answer":"Default gateways provide means for the local networks to connect to the external network.\n\nThe default gateway for connecting to the external network is usually the address of the external router port."
},{"id":"55",
"q":"What is region?",
"answer":"When hierarchical routing is used, the routers are divided into what we will call regions, with each router knowing all the details about how to route packets to destinations within its own region, but knowing nothing about the internal structure of other regions."
},{"id":"56",
"q":"What is silly window syndrome?",
"answer": "It is a problem that can ruin TCP performance.This problem occurs when data are passed to the sending TCP entity in large blocks,but an interactive application on the receiving side reads 1 byte at a time."
},{"id":"57",
"q":"What is traffic shaping?",
"answer":"One of the main causes of congestion is that traffic is often busy.\n\nIf hosts could be made to transmit at a uniform rate, congestion would be less common.\n\nAnother open loop method to help manage congestion is forcing the packet to be transmitted at a more predictable rate.This is called traffic shaping."
},{"id":"58",
"q":"Explain 5-4-3 rule? ",
"answer":"In a Ethernet network, between any two points on the network ,there can be no more than five network segments or four repeaters, and of those five segments only three of segments can be populated."
},{"id":"59",
"q":"What are major types of networks and explain?",
"answer":"Server-based network: provide centralized control of network resources and rely on server computers to provide security and network administration\n\nPeer-to-peer network: computers can act as both servers sharing resources and as clients using the resources."
},{"id":"60",
"q":"What is the minimum and maximum length of the header in the TCP segment and IP datagram?",
"answer":"The header should have a minimum length of 20 bytes and can have a maximum length of 60 bytes. "
},{"id":"61",
"q":"What is difference between ARP and RARP?",
"answer":"The address resolution protocol (ARP) is used to associate the 32 bit IP address with the 48 bit physical address, used by a host or a router to find the physical address of another host on its network by sending a ARP query packet that includes the IP address of the receiver.\n\nThe reverse address resolution protocol (RARP) allows a host to discover its Internet address when it knows only its physical address."
},
{"id":"62",
"q":"What is Protocol Data Unit?",
"answer":"The data unit in the LLC level is called the protocol data unit (PDU).\n\nThe PDU contains of four fields a destination service access point (DSAP), a source service access point (SSAP), a control field and an information field. DSAP, SSAP are addresses used by the LLC to identify the protocol stacks on the receiving and sending machines that are generating and using the data.\n\nThe control field specifies whether the PDU frame is a information frame (I – frame) or a supervisory frame (S – frame) or a unnumbered frame (U – frame)."
},
{"id":"63",
"q":"What is Bit Stuffing? ",
"answer":"Bit stuffing is the process of adding one extra 0 whenever five consecutive Is follow a 0 in the data,so that the receiver does not mistake the pattern 0111110 for a flag."
},
{"id":"64",
"q":"What are Cyclic Codes?",
"answer":"Cyclic codes are special linear block codes with one extra property. In a cyclic code, if a codeword is cyclically shifted (rotated), the result is another codeword."
},
{"id":"65",
"q":"What is Forward Error Correction?",
"answer":"Forward error correction is the process in which the receiver tries to guess the message by using redundant bits."
},
{"id":"66",
"q":"What is CRC?",
"answer":"CRC, is the most powerful of the redundancy checking techniques, is based on binary division."
},
{"id":"67",
"q":"What is LRC?",
"answer":"In LRC, a block of bits is divided into rows and a redundant row of bits is added to the whole block. It can detect burst errors. If two bits in one data unit are damaged and bits in exactly the same positions in another data unit are also damaged, the LRC checker will not detect an error. In LRC a redundant data unit follows n data units."
},
{"id":"68",
"q":"What is VRC?",
"answer":" It is the most common and least expensive mechanism for Error Detection.\n\nIn VRC, a parity bit is added to every data unit so that the total number of 1s becomes even for even parity.\n\nIt can detect all single-bit errors.\n\nIt can detect burst errors only if the total number of errors in each data unit is odd."
},
{"id":"69",
"q":"What is Redundancy?",
"answer":"The concept of including extra information in the transmission solely for the purpose of comparison. This technique is called redundancy."
},
{"id":"70",
"q":"What are the two classes of hardware building blocks?",
"answer":"Nodes and Links"
},
{"id":"71",
"q":"What are different link types used to build a computer network?",
"answer":"Cables\n\nLeased Lines\n\nLast-Mile Links\n\nWireless Links"
},
{"id":"72",
"q":"Define Retransmission?",
"answer":"Retransmission is a technique in which the receiver detects the occurrence of an error and asks the sender to resend the message.\n\nResending is repeated until a message arrives that the receiver believes is error-freed."
},
{"id":"73",
"q":"What are Code Words?",
"answer":" “r” redundant bits are added to each block to make the length n = k + r.The resulting n-bit blocks are called codewords. 2n – 2k codewords that are not used. These codewords are invalid or illegal."
},
{"id":"74",
"q":"Which factors mark the reliability of the network?",
"answer":"Frequency of failure\n\nDowntime / Time taken for recovery."
},
{"id":"75",
"q":"When is a switch said to be congested?",
"answer":"Sometimes a switch receives the packets faster than they can be accommodated in the shared link. These packets are stored in the memory for sometime.\n\nHowever, after sometime the buffer space will exhaust and some packets will start getting dropped off.The switch is called as congested in this state."
},
{"id":"76",
"q":"What are the various types of Multiplexing? ",
"answer":"The various types of multiplexing are:\n\nFrequency Division Multiplexing (FDM)\n\nTime Division Multiplexing (TDM)\n\nSynchronous TDM\n\nAsynchronous TDM\n\nWave Division Multiplexing (WDM)"
},
{"id":"77",
"q":"Which layers of OSI are referred to as network support layers?",
"answer":"Physical Layer\n\nData link Layer and\n\nNetwork Layers"
},
{"id":"78",
"q":"What is NIC?",
"answer":" NIC stands for Network Interface Card.It is a peripheral card attached to a PC to helps it connect to a network.The MAC address of the card helps the network in identifying the PC."
},
{"id":"79",
"q":"What is Bit Stuffing?",
"answer":" Bit stuffing means adding one extra 0 whenever five consecutive 1s follow a 0.This is done so that the pattern 0111110 is not mistaken for a flag."
},
{"id":"80",
"q":"Why acknowledged service is better?",
"answer":"When data is sent acknowledgement at reception of data occurs.\n\nIf frame is lost, then error is detected and the data is sent again.\n\nRecovery of data takes place easily.\n\nIt works for reliable channels where error is minimum.\n\nThis is a time saving method and better than unacknowledged service ."
},{"id":"81",
"q":"What is UART.",
"answer":"Called Universal asynchronous receiver transmitter.\n\nSerial to parrallel conversion of data takes place at transmitter and vice –versa occurs at reciever.\n\nStart and stop bits are send with data without any clock pulses for synchronization .\n\nFormating of Data in Transmitter and Receiver takes place.\n\nAlso allows Voltage level conversion at both ends. Error detection and correction and bits synchronization is possible and data is sent in form of bytes."
},{"id":"82",
"q":"What is the main purpose of OSPF?",
"answer":"OSPF, or Open Shortest Path First, is a link-state routing protocol that uses routing tables to determine the best possible path for data exchange."
},
{"id":"83",
"q":" What are firewalls??",
"answer":"Firewalls serve to protect an internal network from external attacks. These external threats can be hackers who want to steal data or computer viruses that can wipe out data in an instant. It also prevents other users from external networks from gaining access to the private network."
},{"id":"84",
"q":"Describe star topology?",
"answer":" Star topology consists of a central hub that connects to nodes. This is one of the easiest to setup and maintain."
},{"id":"85",
"q":"What are gateways?",
"answer":"Gateways provide connectivity between two or more network segments.It is usually a computer that runs the gateway software and provides translation services.This translation is a key in allowing different systems to communicate on the network."
},{"id":"86",
"q":"What is SLIP?",
"answer":"SLIP, or Serial Line Interface Protocol, is actually an old protocol developed during the early UNIX days.This is one of the protocols that are used for remote access."
},
{"id":"87",
"q":"Describe star topology",
"answer":"Star topology consists of a central hub that connects to nodes. This is one of the easiest to setup and maintain."
},
{"id":"88",
"q":"What is NOS?",
"answer":"NOS, or Network Operating System, is specialized software whose main task is to provide network connectivity to a computer in order for it to be able to communicate with other computers and connected devices."
},
{"id":"89",
"q":" What is a private IP address?",
"answer":"Private IP addresses are assigned for use on intranets. These addresses are used for internal networks and are not routable on external public networks. These ensures that no conflicts are present among internal networks while at the same time the same range of private IP addresses are reusable for multiple intranets since they do not “see” each other."
},
{"id":"90",
"q":" What is DoS?",
"answer":"DoS, or Denial-of-Service attack, is an attempt to prevent users from being able to access the internet or any other network services. Such attacks may come in different forms and are done by a group of perpetuators. One common method of doing this is to overload the system server so it cannot anymore process legitimate traffic and will be forced to reset."
},
{"id":"91",
"q":"What is RIP?",
"answer":" RIP, short for Routing Information Protocol is used by routers to send data from one network to another. It efficiently manages routing data by broadcasting its routing table to all other routers within the network. It determines the network distance in units of hops."
},
{"id":"92",
"q":"What does 10Base-T mean?",
"answer":" The 10 refers to the data transfer rate, in this case is 10Mbps. The word Base refers to base band, as oppose to broad band. T means twisted pair, which is the cable used for that network."
},
{"id":"93",
"q":"What are MAC addresses?",
"answer":" MAC, or Media Access Control, uniquely identifies a device on the network. It is also known as physical address or Ethernet address. A MAC address is made up of 6-byte parts."
},
{"id":"94",
"q":" Briefly describe NAT.?",
"answer":"NAT is Network Address Translation.This is a protocol that provides a way for multiple computers on a common network to share single connection to the Internet. "
},
{"id":"95",
"q":"What is attenuation?",
"answer":"The degeneration of a signal over distance on a network cable is called attenuation"
},
{"id":"96",
"q":"What is cladding?",
"answer":"A layer of a glass surrounding the centre fibre of glass inside a fiber-optic cable"
},{"id":"97",
"q":"What is Project 802?",
"answer":"It is a project started by IEEE to set standards to enable intercommunication between equipment from a variety of manufacturers. It is a way for specifying functions of the physical layer, the data link layer and to some extent the network layer to allow for interconnectivity of major LAN protocols.\n\nIt consists of the following:\n\n802.1 is an internetworking standard for compatibility of different LANs and MANs across protocols.\n\n802.2 Logical link control (LLC) is the upper sublayer of the data link layer which is non-architecture-specific, that is remains the same for all IEEE-defined LANs.\n\nMedia access control (MAC) is the lower sublayer of the data link layer that contains some distinct modules each carrying proprietary information specific to the LAN product being used. The modules are Ethernet LAN (802.3), Token ring LAN (802.4), Token bus LAN (802.5).\n\n802.6 is distributed queue dual bus (DQDB) designed to be used in MANs."
},{"id":"98",
"q":" What is wide-mouth frog?",
"answer":"Wide-mouth frog is the simplest known key distribution centre (KDC) authentication protocol."
},{"id":"99",
"q":"What is Mail Gateway?",
"answer":"It is a system that performs a protocol translation between different electronic mail delivery protocols."
},
{"id":"100",
"q":"What is redirector?",
"answer":" Redirector is software that intercepts file or prints I/O requests and translates them into network requests. This comes under presentation layer. "
}
]
}
"iq":[{"id":"1",
"q":"What is Network?",
"answer":"A network is a set of devices connected by physical media links.A network is recursively is a connection of two or more nodes by a physical link or two or more networks connected by one or more nodes. "
},
{"id":"2",
"q":"What is a Link? ",
"answer":"A link refers to the connectivity between two devices.It includes the type of cables and protocols used in order for one device to be able to communicate with the other. "
},
{"id":"3",
"q":"What is a node?",
"answer":"A network can consist of two or more computers directly connected by some physical medium such as coaxial cable or optical fiber.Such a physical medium is called as Links and the computer it connects is called as Nodes."
},
{"id":"4",
"q":"What is a gateway or Router?",
"answer":"A node that is connected to two or more networks is commonly called as router or Gateway.It generally forwards message from one network to another. "
},
{"id":"5",
"q":"What is point-point link? ",
"answer":"If the physical links are limited to a pair of nodes it is said to be point-point link."
},
{"id":"6",
"q":"What is Multiple Access? ",
"answer":"If the physical links are shared by more than two nodes, it is said to be Multiple Access. "
},
{"id":"7",
"q":"What is a gateway or Router?",
"answer":"A node that is connected to two or more networks is commonly called as router or Gateway. It generally forwards message from one network to another."
},
{"id":"8",
"q":"What are the advantages of Distributed Processing?",
"answer":"Security/Encapsulation\n\nDistributed database\n\nFaster Problem solving\n\nSecurity through redundancy\n\nCollaborative Processing"
},
{"id":"9",
"q":"What is backbone network?",
"answer":"A backbone network is a centralized infrastructure that is designed to distribute different routes and data to various networks. It also handles management of bandwidth and various channels."
},
{"id":"10",
"q":" What is a LAN?",
"answer":"LAN is short for Local Area Network. It refers to the connection between computers and other network devices that are located within a small physical location."
},
{"id":"11",
"q":"What is anonymous FTP?",
"answer":"Anonymous FTP is a way of granting user access to files in public servers. Users that are allowed access to data in these servers do not need to identify themselves, but instead log in as an anonymous guest."
},
{"id":"12",
"q":"What is subnet mask?",
"answer":"A subnet mask is combined with an IP address in order to identify two parts:the extended network address and the host address. Like an IP address, a subnet mask is made up of 32 bits."
},
{"id":"13",
"q":"What is the maximum length allowed for a UTP cable?",
"answer":"A single segment of UTP cable has an allowable length of 90 to 100 meters. This limitation can be overcome by using repeaters and switches."
},
{"id":"14",
"q":"What is data encapsulation?",
"answer":"Data encapsulation is the process of breaking down information into smaller manageable chunks before it is transmitted across the network. It is also in this process that the source and destination addresses are attached into the headers, along with parity checks."
},
{"id":"15",
"q":" Describe Network Topology?",
"answer":" Network Topology refers to the layout of a computer network.It shows how devices and cables are physically laid out, as well as how they connect to one another. "
},
{"id":"16",
"q":"Define Routing?",
"answer":"The process of determining systematically hoe to forward messages toward the destination nodes based on its address is called routing."
},
{"id":"17",
"q":"What is semantic gap?",
"answer":"Defining a useful channel involves both understanding the applications requirements and recognizing the limitations of the underlying technology. The gap between what applications expects and what the underlying technology can provide is called semantic gap. "
},
{"id":"18",
"q":"What is Round Trip Time?",
"answer":"The duration of time it takes to send a message from one end of a network to the other and back, is called RTT."
},
{"id":"19",
"q":"Describe Domain Name System.?",
"answer":"There are two types of client/server programs.First is used directly by the user, such as e-mail, Second supports other application programs. The Domain Name System (DNS) is a supporting program that is used by other programs such as to find the IP address of an e-mail recipient."
},
{"id":"20",
"q":"Describe Hierarchical Namespace.?",
"answer":"In a hierarchical name space, each name is combination of several parts as:\n\nType of the organization.\n\nName of an organization.\n\nDepartments in the organization.\n\nA central authority can assign the part of the name that defines the nature and name of the organization. The other things of the name the organization provides itself. The organization can add suffixes (or prefixes) to the name to define its host.\n\nThe company need not worry about the prefix if it is same as that of another organization because, even if part of an address is the same, the whole address is different."
},
{"id":"21",
"q":"What is the POP3 protocol.?",
"answer":"Post Office Protocol, version 3 is used for accessing the message. POP3 is very simple protocol and has limited functionality. POP has different version but currently version 3 is used. A POP3 server listens on well-known port 110. POP3 supports two types of mode.\n\nDelete Mode: In this mode, the mail is deleted from the mailbox after each retrieval.\n\nKeep Mode. The mail remains in the mailbox after retrieval. "
},
{"id":"22",
"q":"What is Anonymous FTP?",
"answer":"Some sites provide the functionality that user can access the file with limited access. To access these files, a user does not need to have an account or password. For using FTP, the user enters \"anonymous\" as a user ID and guest as password. Usually, you can enter anything as a password. "
},
{"id":"23",
"q":"What is User Agent?",
"answer":"User agent is a software that provides the service to the user to make the process of sending and receiving a message easier. The following are User Agent services."
},{"id":"24",
"q":" what is Channelization in networks.? ",
"answer":"Channelization is a multiple-access method in which the available bandwidth of a link is shared in time, frequency, or through code, between different stations.There are three basic approaches to achieve channelization."
},{"id":"25",
"q":"Differentiate between hub and switch.?",
"answer":"Hub is a layer 1 device while Switch is layer 2 device.Hub works on single collision and single broadcast domain while switch works on per port collision and single broadcast domain."
},{"id":"26",
"q":"What is peer to peer?",
"answer":"Peer to peer are networks that does not reply on a server.All PCs on this network act as individual workstations."
},{"id":"27",
"q":"What is ICMP?",
"answer":"ICMP is Internet Control Message Protocol. It provides messaging and communication for protocols within the TCP/IP stack. This is also the protocol that manages error messages that are used by network tools such as PING. "
},{"id":"28",
"q":"What is netstat?",
"answer":"Netstat is a command line utility program.It provides useful information about the current TCP/IP settings of a connection."
},{"id":"29",
"q":"What is the number of network IDs in a Class C network?",
"answer":"For a Class C network, the number of usable Network ID bits is 21.\n\nThe number of possible network IDs is 2 raised to 21 or 2,097,152.\n\nThe number of host IDs per network ID is 2 raised to 8 minus 2, or 254."
},{"id":"30",
"q":" What is DHCP?",
"answer":"DHCP is short for Dynamic Host Configuration Protocol.\n\nIts main task is to automatically assign an IP address to devices across the network.\n\nIt first checks for the next available address not yet taken by any device, then assigns this to a network device."
},{"id":"31",
"q":"What is tracert? ",
"answer":"Tracert is a Windows utility program that can used to trace the route taken by data from the router to the destination network.\n\nIt also shows the number of hops taken during the entire transmission route."
},{"id":"32",
"q":"What are firewalls?",
"answer":"Firewalls serve to protect an internal network from external attacks.These external threats can be hackers who want to steal data or computer viruses that can wipe out data in an instant.It also prevents other users from external networks from gaining access to the private network. "
},{"id":"33",
"q":"What is client/server?",
"answer":"Client/server is a type of network wherein one or more computers act as servers. Servers provide a centralized repository of resources such as printers and files. Clients refers to workstation that access the server. "
},{"id":"34",
"q":" Explain clustering support?",
"answer":"Clustering support refers to the ability of a network operating system to connect multiple servers in a fault-tolerant group. The main purpose of this is the in the event that one server fails, all processing will continue on with the next server in the cluster."
},
{"id":"35",
"q":"What is redirector?",
"answer":" Redirector is software that intercepts file or prints I/O requests and translates them into network requests. This comes under presentation layer. "
},
{"id":"36",
"q":" What is multicast routing?",
"answer":"Multicast routing is a targeted form of broadcasting that sends message to a selected group of user, instead of sending it to all users on a subnet."
},
{"id":"37",
"q":" How are IP addresses arranged and displayed?",
"answer":"IP addresses are displayed as a series of four decimal numbers that are separated by period or dots.Another term for this arrangement is the dotted decimal format.\n\nAn example is 192.168.101.2 "
},{"id":"38",
"q":"What is mesh topology?",
"answer":"Mesh topology is a setup wherein each device is connected directly to every other device on the network.\n\nConsequently, it requires that each device have at least two network connections."
},{"id":"39",
"q":" What is RSA algorithm?",
"answer":"RSA is short for Rivest-Shamir-Adleman algorithm.It is the most commonly used public key encryption algorithm in use today."
},{"id":"40",
"q":"What protocols fall under the TCP/IP Internet Layer?",
"answer":"There are 4 protocols that are being managed by this layer. These are ICMP, IGMP, IP and ARP."
},{"id":"41",
"q":"What is the difference between TFTP and FTP application layer protocols?",
"answer":"The Trivial File Transfer Protocol (TFTP) allows a local host to obtain files from a remote host but does not provide reliability or security.\n\nIt uses the fundamental packet delivery services offered by UDP.\n\nThe File Transfer Protocol (FTP) is the standard mechanism provided by TCP / IP for copying a file from one host to another.\n\nIt uses the services offer by TCP and so is reliable and secure.\n\nIt establishes two connections (virtual circuits) between the hosts,one for data transfer and another for control information."
},{"id":"42",
"q":"What MAU?",
"answer":"In token Ring , hub is called Multi-station Access Unit(MAU)."
},
{"id":"43",
"q":"Why should you care about the OSI Reference Model?·",
"answer":"It provides a framework for discussing network operations and design."
},{"id":"44",
"q":"What is SAP?",
"answer":" Series of interface points that allow other computers to communicate with the other layers of network protocol stack."
},{"id":"45",
"q":"What do you meant by \"triple X\" in Networks?",
"answer":"The function of PAD (Packet Assembler Disassembler) is described in a document known as X.3. The standard protocol has been defined between the terminal and the PAD, called X.28;\n\nanother standard protocol exists between hte PAD and the network, called X.29. Together, these three recommendations are often called \"triple X\"."
},{"id":"46",
"q":"Difference between the communication and transmission.?",
"answer":"Transmission is a physical movement of information and concern issues like bit polarity, synchronisation, clock etc.\n\nCommunication means the meaning full exchange of information between two communication media. "
},{"id":"47",
"q":" What is Beaconing?",
"answer":"The process that allows a network to self-repair networks problems. The stations on the network notify the other stations on the ring when they are not receiving the transmissions. Beaconing is used in Token ring and FDDI networks."
},{"id":"48",
"q":"What is IPv6?",
"answer":"IPv6 , or Internet Protocol version 6, was developed to replace IPv4.\n\nAt present, IPv4 is being used to control internet traffic, butis expected to get saturated in the near future.\n\nIPv6 was designed to overcome this limitation."
},
{"id":"49",
"q":"What is sneakernet? ",
"answer":"Sneakernet is believed to be the earliest form of networking wherein data is physically transported using removable media, such as disk, tapes. "
},{"id":"50",
"q":" What is one advantage of mesh topology?",
"answer":"In the event that one link fails, there will always be another available. Mesh topology is actually one of the most fault-tolerant network topology."
},
{"id":"51",
"q":"What can be done to fix signal attenuation problems?",
"answer":"A common way of dealing with such a problem is to use repeaters and hub,because it will help regenerate the signal and therefore prevent signal loss.Checking if cables are properly terminated is also a must."
},
{"id":"52",
"q":"What is ipconfig?",
"answer":"Ipconfig is a utility program that is commonly used to identify the addresses information of a computer on a network.It can show the physical address as well as the IP address."
},{"id":"53",
"q":"What common software problems can lead to network defects?",
"answer":"Software related problems can be any or a combination of the following:\n\n– client server problems\n\n– application conflicts\n\n– error in configuration\n\n– protocol mismatch\n\n– security issues\n\n– user policy and rights issues "
},{"id":"54",
"q":"What is the use of a default gateway?",
"answer":"Default gateways provide means for the local networks to connect to the external network.\n\nThe default gateway for connecting to the external network is usually the address of the external router port."
},{"id":"55",
"q":"What is region?",
"answer":"When hierarchical routing is used, the routers are divided into what we will call regions, with each router knowing all the details about how to route packets to destinations within its own region, but knowing nothing about the internal structure of other regions."
},{"id":"56",
"q":"What is silly window syndrome?",
"answer": "It is a problem that can ruin TCP performance.This problem occurs when data are passed to the sending TCP entity in large blocks,but an interactive application on the receiving side reads 1 byte at a time."
},{"id":"57",
"q":"What is traffic shaping?",
"answer":"One of the main causes of congestion is that traffic is often busy.\n\nIf hosts could be made to transmit at a uniform rate, congestion would be less common.\n\nAnother open loop method to help manage congestion is forcing the packet to be transmitted at a more predictable rate.This is called traffic shaping."
},{"id":"58",
"q":"Explain 5-4-3 rule? ",
"answer":"In a Ethernet network, between any two points on the network ,there can be no more than five network segments or four repeaters, and of those five segments only three of segments can be populated."
},{"id":"59",
"q":"What are major types of networks and explain?",
"answer":"Server-based network: provide centralized control of network resources and rely on server computers to provide security and network administration\n\nPeer-to-peer network: computers can act as both servers sharing resources and as clients using the resources."
},{"id":"60",
"q":"What is the minimum and maximum length of the header in the TCP segment and IP datagram?",
"answer":"The header should have a minimum length of 20 bytes and can have a maximum length of 60 bytes. "
},{"id":"61",
"q":"What is difference between ARP and RARP?",
"answer":"The address resolution protocol (ARP) is used to associate the 32 bit IP address with the 48 bit physical address, used by a host or a router to find the physical address of another host on its network by sending a ARP query packet that includes the IP address of the receiver.\n\nThe reverse address resolution protocol (RARP) allows a host to discover its Internet address when it knows only its physical address."
},
{"id":"62",
"q":"What is Protocol Data Unit?",
"answer":"The data unit in the LLC level is called the protocol data unit (PDU).\n\nThe PDU contains of four fields a destination service access point (DSAP), a source service access point (SSAP), a control field and an information field. DSAP, SSAP are addresses used by the LLC to identify the protocol stacks on the receiving and sending machines that are generating and using the data.\n\nThe control field specifies whether the PDU frame is a information frame (I – frame) or a supervisory frame (S – frame) or a unnumbered frame (U – frame)."
},
{"id":"63",
"q":"What is Bit Stuffing? ",
"answer":"Bit stuffing is the process of adding one extra 0 whenever five consecutive Is follow a 0 in the data,so that the receiver does not mistake the pattern 0111110 for a flag."
},
{"id":"64",
"q":"What are Cyclic Codes?",
"answer":"Cyclic codes are special linear block codes with one extra property. In a cyclic code, if a codeword is cyclically shifted (rotated), the result is another codeword."
},
{"id":"65",
"q":"What is Forward Error Correction?",
"answer":"Forward error correction is the process in which the receiver tries to guess the message by using redundant bits."
},
{"id":"66",
"q":"What is CRC?",
"answer":"CRC, is the most powerful of the redundancy checking techniques, is based on binary division."
},
{"id":"67",
"q":"What is LRC?",
"answer":"In LRC, a block of bits is divided into rows and a redundant row of bits is added to the whole block. It can detect burst errors. If two bits in one data unit are damaged and bits in exactly the same positions in another data unit are also damaged, the LRC checker will not detect an error. In LRC a redundant data unit follows n data units."
},
{"id":"68",
"q":"What is VRC?",
"answer":" It is the most common and least expensive mechanism for Error Detection.\n\nIn VRC, a parity bit is added to every data unit so that the total number of 1s becomes even for even parity.\n\nIt can detect all single-bit errors.\n\nIt can detect burst errors only if the total number of errors in each data unit is odd."
},
{"id":"69",
"q":"What is Redundancy?",
"answer":"The concept of including extra information in the transmission solely for the purpose of comparison. This technique is called redundancy."
},
{"id":"70",
"q":"What are the two classes of hardware building blocks?",
"answer":"Nodes and Links"
},
{"id":"71",
"q":"What are different link types used to build a computer network?",
"answer":"Cables\n\nLeased Lines\n\nLast-Mile Links\n\nWireless Links"
},
{"id":"72",
"q":"Define Retransmission?",
"answer":"Retransmission is a technique in which the receiver detects the occurrence of an error and asks the sender to resend the message.\n\nResending is repeated until a message arrives that the receiver believes is error-freed."
},
{"id":"73",
"q":"What are Code Words?",
"answer":" “r” redundant bits are added to each block to make the length n = k + r.The resulting n-bit blocks are called codewords. 2n – 2k codewords that are not used. These codewords are invalid or illegal."
},
{"id":"74",
"q":"Which factors mark the reliability of the network?",
"answer":"Frequency of failure\n\nDowntime / Time taken for recovery."
},
{"id":"75",
"q":"When is a switch said to be congested?",
"answer":"Sometimes a switch receives the packets faster than they can be accommodated in the shared link. These packets are stored in the memory for sometime.\n\nHowever, after sometime the buffer space will exhaust and some packets will start getting dropped off.The switch is called as congested in this state."
},
{"id":"76",
"q":"What are the various types of Multiplexing? ",
"answer":"The various types of multiplexing are:\n\nFrequency Division Multiplexing (FDM)\n\nTime Division Multiplexing (TDM)\n\nSynchronous TDM\n\nAsynchronous TDM\n\nWave Division Multiplexing (WDM)"
},
{"id":"77",
"q":"Which layers of OSI are referred to as network support layers?",
"answer":"Physical Layer\n\nData link Layer and\n\nNetwork Layers"
},
{"id":"78",
"q":"What is NIC?",
"answer":" NIC stands for Network Interface Card.It is a peripheral card attached to a PC to helps it connect to a network.The MAC address of the card helps the network in identifying the PC."
},
{"id":"79",
"q":"What is Bit Stuffing?",
"answer":" Bit stuffing means adding one extra 0 whenever five consecutive 1s follow a 0.This is done so that the pattern 0111110 is not mistaken for a flag."
},
{"id":"80",
"q":"Why acknowledged service is better?",
"answer":"When data is sent acknowledgement at reception of data occurs.\n\nIf frame is lost, then error is detected and the data is sent again.\n\nRecovery of data takes place easily.\n\nIt works for reliable channels where error is minimum.\n\nThis is a time saving method and better than unacknowledged service ."
},{"id":"81",
"q":"What is UART.",
"answer":"Called Universal asynchronous receiver transmitter.\n\nSerial to parrallel conversion of data takes place at transmitter and vice –versa occurs at reciever.\n\nStart and stop bits are send with data without any clock pulses for synchronization .\n\nFormating of Data in Transmitter and Receiver takes place.\n\nAlso allows Voltage level conversion at both ends. Error detection and correction and bits synchronization is possible and data is sent in form of bytes."
},{"id":"82",
"q":"What is the main purpose of OSPF?",
"answer":"OSPF, or Open Shortest Path First, is a link-state routing protocol that uses routing tables to determine the best possible path for data exchange."
},
{"id":"83",
"q":" What are firewalls??",
"answer":"Firewalls serve to protect an internal network from external attacks. These external threats can be hackers who want to steal data or computer viruses that can wipe out data in an instant. It also prevents other users from external networks from gaining access to the private network."
},{"id":"84",
"q":"Describe star topology?",
"answer":" Star topology consists of a central hub that connects to nodes. This is one of the easiest to setup and maintain."
},{"id":"85",
"q":"What are gateways?",
"answer":"Gateways provide connectivity between two or more network segments.It is usually a computer that runs the gateway software and provides translation services.This translation is a key in allowing different systems to communicate on the network."
},{"id":"86",
"q":"What is SLIP?",
"answer":"SLIP, or Serial Line Interface Protocol, is actually an old protocol developed during the early UNIX days.This is one of the protocols that are used for remote access."
},
{"id":"87",
"q":"Describe star topology",
"answer":"Star topology consists of a central hub that connects to nodes. This is one of the easiest to setup and maintain."
},
{"id":"88",
"q":"What is NOS?",
"answer":"NOS, or Network Operating System, is specialized software whose main task is to provide network connectivity to a computer in order for it to be able to communicate with other computers and connected devices."
},
{"id":"89",
"q":" What is a private IP address?",
"answer":"Private IP addresses are assigned for use on intranets. These addresses are used for internal networks and are not routable on external public networks. These ensures that no conflicts are present among internal networks while at the same time the same range of private IP addresses are reusable for multiple intranets since they do not “see” each other."
},
{"id":"90",
"q":" What is DoS?",
"answer":"DoS, or Denial-of-Service attack, is an attempt to prevent users from being able to access the internet or any other network services. Such attacks may come in different forms and are done by a group of perpetuators. One common method of doing this is to overload the system server so it cannot anymore process legitimate traffic and will be forced to reset."
},
{"id":"91",
"q":"What is RIP?",
"answer":" RIP, short for Routing Information Protocol is used by routers to send data from one network to another. It efficiently manages routing data by broadcasting its routing table to all other routers within the network. It determines the network distance in units of hops."
},
{"id":"92",
"q":"What does 10Base-T mean?",
"answer":" The 10 refers to the data transfer rate, in this case is 10Mbps. The word Base refers to base band, as oppose to broad band. T means twisted pair, which is the cable used for that network."
},
{"id":"93",
"q":"What are MAC addresses?",
"answer":" MAC, or Media Access Control, uniquely identifies a device on the network. It is also known as physical address or Ethernet address. A MAC address is made up of 6-byte parts."
},
{"id":"94",
"q":" Briefly describe NAT.?",
"answer":"NAT is Network Address Translation.This is a protocol that provides a way for multiple computers on a common network to share single connection to the Internet. "
},
{"id":"95",
"q":"What is attenuation?",
"answer":"The degeneration of a signal over distance on a network cable is called attenuation"
},
{"id":"96",
"q":"What is cladding?",
"answer":"A layer of a glass surrounding the centre fibre of glass inside a fiber-optic cable"
},{"id":"97",
"q":"What is Project 802?",
"answer":"It is a project started by IEEE to set standards to enable intercommunication between equipment from a variety of manufacturers. It is a way for specifying functions of the physical layer, the data link layer and to some extent the network layer to allow for interconnectivity of major LAN protocols.\n\nIt consists of the following:\n\n802.1 is an internetworking standard for compatibility of different LANs and MANs across protocols.\n\n802.2 Logical link control (LLC) is the upper sublayer of the data link layer which is non-architecture-specific, that is remains the same for all IEEE-defined LANs.\n\nMedia access control (MAC) is the lower sublayer of the data link layer that contains some distinct modules each carrying proprietary information specific to the LAN product being used. The modules are Ethernet LAN (802.3), Token ring LAN (802.4), Token bus LAN (802.5).\n\n802.6 is distributed queue dual bus (DQDB) designed to be used in MANs."
},{"id":"98",
"q":" What is wide-mouth frog?",
"answer":"Wide-mouth frog is the simplest known key distribution centre (KDC) authentication protocol."
},{"id":"99",
"q":"What is Mail Gateway?",
"answer":"It is a system that performs a protocol translation between different electronic mail delivery protocols."
},
{"id":"100",
"q":"What is redirector?",
"answer":" Redirector is software that intercepts file or prints I/O requests and translates them into network requests. This comes under presentation layer. "
}
]
}