Category: Computer Networks Objective Questions

Computer Networks Questions and Answers for Campus interviews on “STP (Shielded Twisted Pair) Cables”.

1. _____________ allows LAN users to share computer programs and data.
a) Communication server
b) Print server
c) File server
d) Network

Answer: c
Clarification: A file server allows LAN users to share computer programs and data. It uses the File Transfer Protocol to provide this feature on ports 20 and 21. The file server works as a medium for the transfer.

2. With respect to physical media, STP cables stands for _________
a) Shielded Twisted Pair Cable
b) Spanning Tree Protocol Cable
c) Static Transport Protocol Cable
d) Shielded Two Power Cable

Answer: a
Clarification: For physical media, STP cable stands for Shielded twisted pair cable. 100 Mbps is the max data capacity of STP cable and its default connector is RJ45. It is popularly used in LANs due to its ease of maintenance and installation.

3. A standalone program that has been modified to work on a LAN by including concurrency controls such as file and record locking is an example of ___________
a) LAN intrinsic software
b) LAN aware software
c) Groupware
d) LAN ignorant software

Answer: a
Clarification: A standalone program that has been modified to work on a LAN by including concurrency controls such as file and record locking is an example of LAN intrinsic software. They are used to give better functionality of the program and the applications working over it to the users of the LAN.

4. The __________ portion of LAN management software restricts access, records user activities and audit data, etc.
a) Configuration management
b) Security management
c) Performance management
d) Recovery management

Answer: b
Clarification: The Security management portion of LAN management software restricts access, records user activities, and audit data. It is responsible for controlling access to the network based on predefined policy. The security management ensures authentication, confidentiality, and integrity in the LAN.

5. What is the max length of the Shielded twisted pair cable?
a) 100 ft
b) 200 ft
c) 100 m
d) 200 m

Answer: c
Clarification: The max the Shielded twisted pair cable is 100 meters. If the length exceeds 100 meters, the loss of signals flowing through the cable would be really high. Thus, STP cable is more suitable for smaller networks like LANs.

6. What is the max data transfer rate of STP cables?
a) 10 Mbps
b) 100 Mbps
c) 1000 Mbps
d) 10000 Mbps

Answer: b
Clarification: 100 Mbps is the max data transfer rate that can be handled by STP cables, and its default connector is RJ-45. 100 Mbps is a feasible data transfer rate for small networks like LANs.

7. Which connector does the STP cable use?
a) BNC
b) RJ-11
c) RJ-45
d) RJ-69

Answer: c
Clarification: RJ-45 is used for STP cable. 100 Mbps is the max data transfer rate that can be handled by STP. RJ-45 is popularly used to connect to modern-day routers, computer network cards, and other network devices.

8. What is the central device in star topology?
a) STP server
b) Hub/switch
c) PDC
d) Router

Answer: b
Clarification: In star topology, no computer is connected to another computer directly but all the computers are connected to a central switch or hub. Every message sent from a source computer goes through the switch or hub and the switch or hub then forwards the message only to the intended destination computer.

9. What is the max data transfer rate for optical fiber cable?
a) 10 Mbps
b) 100 Mbps
c) 1000 Mbps
d) 10000 Mbps

Answer: d
Clarification: Fiber channel speeds have been increasing over the years. 10000 Mbps is the max data transfer rate for optical fiber cables. It is said to be the fastest among the other kinds of cables like STP cables and co-axial cables. People are now using optical fiber cables instead of STP cables for LANs due to their fast data transfer capability.

10. Which of the following architecture uses the CSMA/CD access method?
a) ARC net
b) Ethernet
c) Router
d) STP server

Answer: b
Clarification: Collision detection is not possible in Ethernet without extensions. Collision detection techniques for multiple access like CSMA/CD are used to detect collisions in the Ethernet architecture.

Computer Networks Questions and Answers for Freshers on “SMI”.

1. Storage management comprises of _______________
a) SAN Management
b) Data protection
c) Disk operation
d) All of the mentioned

Answer: d
Clarification: SAN management, data protection and disk operation are the main components of the Storage Management Initiative Specification. SMI-S was developed by the Storage Networking Industry Association.

2. Which of the following is not a storage device?
a) Switch
b) RAID Arrays
c) Tape drives
d) Hub

Answer: d
Clarification: Switches, RAID arrays and tape drives are the main storage devices in SMI-S, while a Hub is simple networking device that cannot be used as storage.

3. Which protocols are used for Storage management?
a) SNMP
b) LDAP
c) POP3
d) MIB

Answer: a
Clarification: Simple Network Management Protocol is used for storage management. Lightweight Directory Access Protocol is used to access or locate information about directories and other resources on a network. Post Office Protocol 3 is used for e-mailing on the internet. Management Information Base is a part of SNMP and contains hierarchically organized information.

4. Identify the difficulty a SAN administrator does not incur while dealing with diverse vendors.
a) Proprietary management interfaces
b) Multiple applications to manage storage in the data center
c) No single view
d) Single view

Answer: d
Clarification: A single view is not possible with diverse vendors present. Proprietary management interfaces, multiple applications management and no single view are the main difficulties incurred by a SAN administrator in such a situation.

5. How do Storage administrators ensure secure access to storage devices?
a) By using Zoning
b) By putting a physical lock on the storage device
c) By keeping devices shutdown when not in use
d) By keeping devices when used

Answer: a
Clarification: Zoning is a method in SAN that can be used by a storage administrator to specify who can see what in the SAN. Zoning might complicate the scaling process if the size of the SAN increases.

6. Effective Storage management does not include __________
a) security
b) backups
c) reporting
d) connection

Answer: d
Clarification: Connection is the responsibility of the connection manager. Storage management includes management of all necessities such as security, backups and reporting facilities.

7. Among the following, identify which task is not involved in Storage Capacity management?
a) Identifying storage systems are approaching full capacity
b) Monitoring trends for each resource
c) Tracking Total capacity, total used, total available
d) Preventing unauthorized access to the storage

Answer: d
Clarification: Prevention of unauthorized access to storage is the task of Security management. Identifying when the storage is approaching full capacity, monitoring trends, reporting and tracking capacity are the tasks of Storage Capacity management.

8. Effect of open standards like SMI(s) is _______________
a) standardization drives software interoperability and interchange ability
b) breaks the old-style dependence on proprietary methods, trade secrets, and single providers
c) builds a strong foundation on which others can quickly build and innovate
d) all of the mentioned

Answer: d
Clarification: Open standards like SMI-S inculcate a general ideal through which the normal designers are able to easily implement the standard into their software and its scalability. Since it is open-source, nothing is hidden from its users and they can implement it as they like or require to. As a whole lot of time is spent to build it as strong and scalable, it provides an efficient foundation to the designers to build and innovate on.

9. Task of Distributed Management Task Force is not ________
a) to promote interoperability among the management solution providers
b to act as an interface between the various budding technologies and provide solution to manage various environments
c) to track the operation of the different management solution providers
d) to manage the facility by itself if one of the management solution providers fail

Answer: d
Clarification: The Distributed Management Task Force is used just to simplify the overall management of the network. It cannot manage a network facility by itself in case one of the management solution providers fails. It provides an interface for promoting interoperability among management solution providers.

10. SMI-S Standard uses which of the following?
a) Java RMI
b) CIM-XML/HTTP
c) CORBA
d) .NET

Answer: b
Clarification: The Distributed Management Task Force maintains a Common Information Model (CIM) to represent a common set of network objects and their relationships. CIM-XML/HTTP refers to the operations of CIM being performed over HTTP or XML. SMI-S uses CIM-XML/HTTP.

Computer Networks test on “IPv6 Addressing”.

1. Dual-stack approach refers to _________
a) Implementing Ipv4 with 2 stacks
b) Implementing Ipv6 with 2 stacks
c) Node has both IPv4 and IPv6 support
d) Implementing a MAC address with 2 stacks

Answer: c
Clarification: Dual-stack is one of the approaches used to support IPv6 in already existing systems. ISPs are using it as a method to transfer from IPv4 to IPv6 completely eventually due to the lower number of possible available addresses in IPv4.

2. Suppose two IPv6 nodes want to interoperate using IPv6 datagrams, but they are connected to each other by intervening IPv4 routers. The best solution here is ________
a) Use dual-stack approach
b) Tunneling
c) No solution
d) Replace the system

Answer: b
Clarification: The IPv4 routers can form a tunnel in which at the sender’s side, the IPv6 datagram is encapsulated in to IPv4, and at the receiver’s side of the tunnel, the IPv4 packet is stripped and the IPv6 packet is sent to the receiver.

3. Teredo is an automatic tunneling technique. In each client the obfuscated IPv4 address is represented by bits ______
a) 96 to 127
b) 0 to 63
c) 80 to 95
d) 64 to 79

Answer: a
Clarification: Teredo is a technique through which gives the possibility for full IPv6 network connectivity to IPv6 capable hosts which are currently on an IPv4 network. Bits 96 to 127 in the datagram represents obfuscated 1Pv4 address of the IPv4 network.

4. A link local address of local addresses is used in an _______
a) Isolated router
b) Isolated mask
c) Isolated subnet
d) Isolated net

Answer: c
Clarification: Isolated subnet is very huge sharing network area in this link local address of local addresses is used. A link local address can be configured on any subnet with the prefix “FE80::”.

5. In subcategories of reserved address in IPv6, address that is used by a host to test itself without going into network is called _________
a) Unspecified address
b) Loopback address
c) Compatible address
d) Mapped address

Answer: b
Clarification: In subcategories of reserved address in IPv6, address that is used by a host to test itself without going into network is called loop back address. IPv6 loopback address is 0000:0000:0000:0000:0000:0000:0000:0001. IPv4 loopback address is 127.0.0.1. It’s a reserved address.

6. A few leftmost bits in each address of IPv6 address define its category is called ________
a) Prefix type
b) Postfix type
c) Reserved type
d) Local type

Answer: a
Clarification: Prefix is the bits in the IP address which are placed in leftmost position. A network prefix in IPv6 is given by a CIDR format-liked number at the end of the address.

7. In IPv6 addresses, addresses that start with eight 0s are called ________
a) Unicast addresses
b) Multicast addresses
c) Any cast addresses
d) Reserved addresses

Answer: d
Clarification: In IPv6 address format, the starting bits are specified with eight 0s to represent reserved addresses. These reserved addresses have a certain function pre-defined like the loop-back address is used to test a network card. Reserved addresses cannot be allotted to a machine.

8. Which statement(s) about IPv6 addresses are true?
a) Leading zeros are required
b) Two colons (::) are used to represent successive hexadecimal fields of zeros
c) Two colons (::) are used to separate fields
d) A single interface cannot have multiple IPv6 addresses of different types

Answer: b
Clarification: In order to shorten the written length of an IPv6 address, successive fields of zeros may be replaced by double colons. In trying to shorten the address further, leading zeros may also be removed. Just as with IPv4, a single device’s interface can have more than one address; with IPv6 there are more types of addresses and the same rule applies. There can be link-local, global unicast, and multicast addresses all assigned to the same interface.

9. When was IPv6 launched?
a) June 2, 2012
b) June 4, 2012
c) June 5, 2012
d) June 6, 2012

Answer: d
Clarification: IPv6 is the latest version of the Internet Protocol released on 6^th June 2012. An IPv6 address is 128 bits long. Therefore, 2¹²⁸ i.e. 340 undecillion addresses are possible in IPv6.

Computer Networks Multiple Choice Questions on “Security In The Internet”.

1. IPSec is designed to provide security at the _________
a) transport layer
b) network layer
c) application layer
d) session layer

Answer: b
Clarification: IPSec is a set of protocols used to provide authentication, data integrity and confidentiality between two machines in an IP network. In the TCP/IP model, it provides security at the IP layer i.e. the network layer.

2. In tunnel mode, IPSec protects the ______
a) Entire IP packet
b) IP header
c) IP payload
d) IP trailer

Answer: a
Clarification: In the tunnel mode, IPSec adds control bits into the packets to encrypt the entire packet between the IPSec endpoints. Using encryption, it provides secure communication between the two endpoints.

3. Network layer firewall works as a ________
a) frame filter
b) packet filter
c) signal filter
d) content filter

Answer: b
Clarification: As you know, firewalls are available as hardware appliances, as software-only, or a combination of the two. In every case, the purpose of a firewall is to isolate your trusted internal network (or your personal PC) from the dangers of unknown resources on the Internet and other network connections that may be harmful. The firewall prevents unauthorized access to your internal, trusted network from outside threats.

4. Network layer firewall has two sub-categories called ____________
a) stateful firewall and stateless firewall
b) bit oriented firewall and byte oriented firewall
c) frame firewall and packet firewall
d) network firewall and data firewall

Answer: a
Clarification: Most network layer firewalls can operate as stateful or stateless firewalls, creating two subcategories of the standard network layer firewall. Stateful firewalls have the advantage of being able to track packets over a period of time for greater analysis and accuracy — but they require more memory and operate more slowly. Stateless firewalls do not analyze past traffic and can be useful for systems where speed is more important than security, or for systems that have very specific and limited needs. For example, a computer that only needs to connect to a particular backup server does not need the extra security of a stateful firewall.

5. WPA2 is used for security in _______
a) ethernet
b) bluetooth
c) wi-fi
d) e-mail

Answer: c
Clarification: WPA2 or WiFi Protected Access 2 is a security protocol used to provide users and firms with strong data security and protection for their wireless networks (WiFi) to give them confidence that only authorized users can access their network.

6. An attempt to make a computer resource unavailable to its intended users is called ______
a) denial-of-service attack
b) virus attack
c) worms attack
d) botnet process

Answer: a
Clarification: In a Denial of Service attack, the attacker won’t let the victims access the network by using a certain method that ensures that an essential network resource is unavailable to the victim. The methods that the attacker can use are vulnerability attack, bandwidth flooding and connection flooding.

7. Extensible authentication protocol is authentication framework frequently used in ______
a) wired personal area network
b) wireless networks
c) wired local area network
d) wired metropolitan area network

Answer: b
Clarification: The Extensible Authentication Protocol (EAP) is an authentication protocol used to connect a network node to the Internet. It designed through extending the methods used by the Point-to-Point Protocol for authentication.

8. Pretty good privacy (PGP) is used in ______
a) browser security
b) email security
c) FTP security
d) wifi security

Answer: b
Clarification: PGP is an encryption method used in e-mail security to encrypt and decrypt the content of an e-mail transmitted over the internet. It makes sure that the message cannot be stolen by other unauthorized users.

9. PGP encrypts data by using a block cipher called ______
a) international data encryption algorithm
b) private data encryption algorithm
c) internet data encryption algorithm
d) local data encryption algorithm

Answer: a
Clarification: The IDEA was designed in 1991 by Xuejia Lai and James Massey. Before IDEA, PGP used the cipher method BassOmatic.

10. When a DNS server accepts and uses incorrect information from a host that has no authority giving that information, then it is called _________
a) DNS lookup
b) DNS hijacking
c) DNS spoofing
d) DNS authorizing

Answer: c
Clarification: In DNS spoofing, also known as DNS cache poisoning, an attacker gets the valid credentials from a victim by spoofing the intended resource, and tricking the victim to give his/her valid authorization credentials.

Computer Networks Multiple Choice Questions on “Network Attacks”.

1. The attacker using a network of compromised devices is known as _____________
a) Internet
b) Botnet
c) Telnet
d) D-net

Answer: b
Clarification: Botnet is a network of compromised devices used by the attacker without the owner’s knowledge to perform unethical activities such as spamming. The attacker usually uses the least secure devices to create the botnet.

2. Which of the following is a form of DoS attack?
a) Vulnerability attack
b) Bandwidth flooding
c) Connection flooding
d) All of the mentioned

Answer: d
Clarification: In a DoS attack, the attacker won’t let the victims access the network by using a certain method that ensures that an essential network resource is unavailable to the victim. In vulnerability attack, the attacker exploits any obvious vulnerable entity in the network to deny the victim access into the network. In bandwidth flooding, the attacker floods the victim with a huge flow of packets and uses up all the bandwidth. In connection flooding, the attacker floods the victim network with a huge number of connections, so that, no other machine can connect to it.

3. The DoS attack, in which the attacker establishes a large number of half-open or fully open TCP connections at the target host is ________
a) Vulnerability attack
b) Bandwidth flooding
c) Connection flooding
d) UDP flooding

Answer: c
Clarification: In Vulnerability attack, the attacker exploits the vulnerable control points of the network to deny access to the victims. In Bandwidth flooding, the attacker intentionally uses up all the bandwidth by flooding the victim with a deluge of packets and makes sure that the victim can’t use any bandwidth. In UDP flooding, too many UDP packets are sent by the attacker to the victim at random ports.

4. The DoS attack, in which the attacker sends deluge of packets to the targeted host is ________
a) Vulnerability attack
b) Bandwidth flooding
c) Connection flooding
d) UDP flooding

Answer: b
Clarification: In Bandwidth flooding, the attacker floods the victim machine with a deluge of packets to make sure that no bandwidth is available. The victim then cannot utilize the complete bandwidth to perform its operation.

5. Packet sniffers involve ____________
a) Active receiver
b) Passive receiver
c) Legal receiver
d) Partially-active receiver

Answer: b
Clarification: The function of packet sniffers is to just silently receive the packets flowing in the channel. If they inject any packets into the channel, they might alert the other users about the intrusion.

6. Sniffers can be prevented by using _______________
a) Wired environment
b) WiFi
c) Ethernet LAN
d) Switched network

Answer: d
Clarification: Switches make sure that the packet is sent to the intended receiver and no one else, thus preventing Sniffers to perform their function. Intelligent switches are hence used preferably for the network.

7. Firewalls are often configured to block ___________
a) UDP traffic
b) TCP traffic
c) Sensitive traffic
d) Best-effort traffic

Answer: a
Clarification: UDP is more vulnerable to attacks, so firewalls are often configured to block suspicious UDP traffic.

8. In a network, If P is the only packet being transmitted and there was no earlier transmission, which of the following delays could be zero?
a) Propagation delay
b) Queuing delay
c) Transmission delay
d) Processing delay

Answer: b
Clarification: Since there is no other packet to be transmitted, there is no need for a queue. Therefore, the delay caused due to the queuing would be none i.e. 0.

Computer Networks Multiple Choice Questions on “SNMP”.

1. The application-level protocol in which a few manager stations control a set of agents is called ______
a) HTML
b) TCP
c) SNMP
d) SNMP/IP

Answer: c
Clarification: SNMP stands for Simple Network Management Protocol. It is an application-level protocol in which a few manager stations control a set of agents. It is used under the TCP/IP protocol suite and is used for managing devices on the internet.

2. Full duplex mode increases the capacity of each domain by ________
a) 10 to 20 mbps
b) 20 to 30 mbps
c) 30 to 40 mbps
d) 40 to 50 mbps

Answer: a
Clarification: In full duplex mode, both endpoints share a single channel bandwidth to achieve two-way transmission. This results in complete utilization of the band capacity increasing the capacity by 10 to 20 mbps than half-duplex mode.

3. Configuration management can be divided into which two subsystems?
a) Reconfiguration and documentation
b) Management and configuration
c) Documentation and dialing up
d) Configuration and dialing up

Answer: a
Clarification: The best current practices report is created by a management group to ensure the most effective configuration management. The group also makes a MIB (Management Information Base) module to help with the configuration management.

4. To use a Simple Network Management System, we need _______
a) Servers
b) IP
c) Protocols
d) Rules

Answer: d
Clarification: Rules are a collection of expression containing parameters to observe the attributes of the user’s device, and then execute some actions. It specifies the parameters for the managed objects inside the application and performs operations that would support the expression. The input of a rule may be many expressions or even a single expression that end in an output of single object invoking some action.

5. The main difference between SNMPv3 and SNMPv2 is _______
a) Management
b) Integration
c) Classification
d) Enhanced security

Answer: d
Clarification: SNMPv3 has introduced new cryptographic security, through which confidentiality is provided by encrypting packets and blocking intruders. It also ensures that the message is coming from a reliable source.

6. In Network Management System, the division that is responsible for controlling access to network based on a predefined policy is called _________
a) Fault Management
b) Secured Management
c) Active Management
d) Security Management

Answer: d
Clarification: Security management is also responsible to provide confidentiality, authentication and encryption in addition to controlling access to network. Without security management, the network and its traffic would be vulnerable to be exploited by attackers.

7. BER stands for ________
a) Basic Encoding Rules
b) Basic Encoding Resolver
c) Basic Encoding Rotator
d) Basic Encoding Router

Answer: a
Clarification: The Basic Encoding Rules are a set of rules that specify the guidelines to encode the SNMP messages in binary form. Each SNMP message is encoded into 3 parts namely data, length and type of message.

8. Control of the users’ access to network resources through charges is the main responsibility of ________
a) Reactive Fault Management
b) Reconfigured Fault Management
c) Accounting Management
d) Security Management

Answer: c
Clarification: The accounting management keeps track of the users and their access rights to the network and controls the user’s access by communicating with the security management. The accounting management takes support of the Management Information Block to perform its operations.

9. SNMP is the framework for managing devices in an internet using the ______
a) TCP/IP protocol
b) UDP
c) SMTP
d) None

Answer: a
Clarification: SNMP is a management protocol in which a few manager stations control a set of agents using the TCP/IP protocol suite. SNMP stands for Simple Network Management Protocol.

10. Structure of Management Information (SMI), is the guideline of ________
a) HTTP
b) SNMP
c) URL
d) MIB

Answer: b
Clarification: SMI was developed by the Storage Networking Industry Association (SNIA) and it defines a standard that can be manipulated by SNMP. Basically, it defines the standard format and hierarchy of management data which is used by the SNMP. It does not describe how the objects are to be managed.