Solved MCQ of EIGRP and OSPF

Solved Objective Questions and Answers for EIGRP and OSPF

1. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?

A.Point-to-point

B.Backbone area 0

C.Broadcast multi-access

D.Non-broadcast multi-access

Answer: Option A

Explanation:

No DR is assigned on any type of point-to-point link. No DR/BDR is assigned on the NBMA point-to-multipoint due to the hub/spoke topology. DR and BDR are elected on broadcast and non-broadcast multi-access networks. Frame Relay is a non-broadcast multi-access (NBMA) network by default. 

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Video Tutorial on STP: Spanning Tree Protocol

STP: Spanning Tree Protocol

"Spanning Tree Protocol (STP) is a Layer 2 protocolthat runs on bridges and switches. The specification for STP is IEEE 802.1D. The main purpose of STP is to ensure that you do not create loops when you have redundant paths in your network".

This video explains basics of  Spanning Tree Protocol and its Practical concepts.

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Interview Questions and Answers for Computer Networking

Interview Questions and Answers for Computer Networking

Questions on Basics of Network and there Types: 

1. what is network?

A network is a set of devices connected by communication medium or channels. A network is recursively is a connection of two or more nodes by a physical medium or two or more networks connected by one or more nodes.

2.What is a link?

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.

3. What is node?

 A node refers to a point or point where a connection takes place. It can be computer or device that is part of a network. Two or more nodes are needed in order to form a network connection.

4. What is point to point link?

It refers to a direct connection between two computers on a network. A point to point connection does not required any other network devices other than connecting a cable to the NIC cards of both computers.

5. What is a LAN?

LAN stands for Local Area Network. LAN is usually restricted to spanning a particular geographic location such as an office building, a single department within a corporate office, or even a home office.

6. What is a MAN?

MAN stands for Metropolitan Area Network. It is a large computer network that usually spans a city or a large campus.  A MAN is optimized for a larger geographical   area than a LAN, ranging from  several blocks of buildings to entire cities.

7. What is a WAN?

WAN stands for Wide Area Network. It is covers a large geographic area such as state, country  or even whole of the world.It is more expensive. Installation and configurations are difficult as compare to LAN and MAN.

8. What are the key design issues of a computer Network?

•  Connectivity
•  Cost-effective Resource Sharing
•  Support for common Services
•  Performance

9. What are the different technologies involved in establishing WAN links?

Analog connections – using conventional telephone lines; Digital connections – using digital-grade telephone lines; switched connections – using multiple sets of links between sender and receiver to move data.

Questions Based on Network Topology's :

1. What is a physical topology and there types?

Physical topology means structural arrangement of computers or other hardware
devices.Types of physical topology's are as follows:
Bus topology, Ring topology, Mesh topology, Star Topology, Hybrid Topology, Point to Point Topology, and Point to Multi-point Topology etc.

2. What is mean by logical topology?

 logical topology means how data flows within a network, regardless of its physical design. And there types are Unicasting, Multicasting and Broadcasting etc.

3. What is backbone network?

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.

4. What is network topology?

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.

5. What is Ring topology?

In a ring topology, device one connects to device two, device two connects to device three, and so on to the last device, which connects back to device one.

6. What is Star topology?

One major disadvantage of star topology is that once the central hub or switch get damaged, the entire network becomes unusable.

7. What is Hybrid topology?

Hybrid topology is the combinations of bus topology and star topology. A hybrid topology is a network setup that makes use of both client-server and peer-to-peer architecture.

8. What is a peer-peer process?

The processes on each machine that communicate at a given layer are called peer-peer process.

9. What is one advantage of mesh topology?

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.

10. How does a network topology affect your decision in setting up a network?

Network topology dictates what media you must use to interconnect devices. It also serves as basis on what materials, connector and terminations that is applicable for the setup.

11. Define the terms Unicasting, Multiccasting and Broadcasting?

• If the message is sent from a source to a single destination node, it is called Unicasting.
• If the message is sent to some subset of other nodes, it is called Multicasting.
• If the message is sent to all the m nodes in the network it is called Broadcasting.

12. What is the difference between CSMA/CD and CSMA/CA?

CSMA/CD, or Collision Detect, retransmits data frames whenever a collision occurred. CSMA/CA, or Collision Avoidance, will first broadcast intent to send prior to data transmission.

14. What are some drawbacks of implementing a ring topology?

In case one workstation on the network suffers a malfunction, it can bring down the entire network. Another drawback is that when there are adjustments and reconfigurations needed to be performed on a particular part of the network, the entire network has to be temporarily brought down as well.

Questions Based on OSI Reference Model: 

1. When were OSI model developed and why its standard called 802.XX and so on?

 OSI stand for Open System Interconnections. OSI model was developed in February 1980 that why these also known as 802.XX Standard Notice 80 means  1980, 2 means February.

2. What are the layer of the OSI reference model?

There are seven layers of OSI model from bottom to top are as Physical layer, Data link layer, Network layer, Transport layer, Session layer, Presentation layer, Application layer.

3. What is layer?

Layer is a completely logical partition of PDU (protocol data unit) process. That define how the information is travel form one computer to other over the network.

4. What is data encapsulation?

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.

5. What is the job of the Network Layer under the OSI reference model?

The Network layer is responsible for data routing, packet switching and control of network congestion. Routers operate under this layer.

6. What is the importance of the OSI Physical Layer?

The physical layer does the conversion from data bits to electrical signal, and vice versa. This is where network devices and cable types are considered and setup.

7. Which layers are network support layers?

•  Physical Layer
•  Data link Layer 
•  Network Layers

8. Which layers are user support layers?

•  Session Layer
•  Presentation Layer 
•  Application Layer

9. What is the function of the OSI Session Layer?

This layer provides the protocols and means for two devices on the network to communicate with each other by holding a session.  This includes setting up the session, managing information exchange during the session, and tear-down process upon termination of the session.

10. What is OSI and what role does it play in computer networks?

OSI (Open Systems Interconnect) serves as a reference model for data communication. It is made up of 7 layers, with each layer defining a particular aspect on how network devices connect and communicate with one another. One layer may deal with the physical media used, while another layer dictates how data is actually transmitted across the network.

11. What are the concerns of the Physical Layer?

Physical layer coordinates the functions required to transmit a bit stream over a physical medium.

a. Physical characteristics of interfaces and media

b. Representation of bits

c. Data rate

d. Synchronization of bits

e. Line configuration

f. Physical topology

g. Transmission mode

12. What are the responsibilities of Data Link Layer?

The Data Link Layer transforms the physical layer, a raw transmission facility, to a reliable link and is responsible for node-node delivery.
a. Framing
b. Physical Addressing
c. Flow Control
d. Error Control
e. Access Control

13. What are the responsibilities of Network Layer?

The Network Layer is responsible for the source-to-destination delivery of packet possibly across multiple networks (links).
a. Logical Addressing
b. Routing

14. What are the responsibilities of Transport Layer?

The Transport Layer is responsible for source-to-destination delivery of the entire message.
a. Service-point Addressing
b. Segmentation and reassembly
c. Connection Control
d. Flow Control
e. Error Control

15.What are the responsibilities of Session Layer?

The Session layer is the network dialog Controller. It establishes, maintains and synchronizes the interaction between the communicating systems.
a. Dialog control
b. Synchronization

16.What are the responsibilities of Presentation Layer?

The Presentation layer is concerned with the syntax and semantics of the information exchanged between two systems.
a. Translation
b. Encryption
c. Compression

17. What are the responsibilities of Application Layer?

The Application Layer enables the user, whether human or software, to access the network. It provides user interfaces and support for services such as e-mail, shared database management and other types of distributed information services.
a. Network virtual Terminal
b. File transfer, access and Management (FTAM)
c. Mail services
d. Directory Services

18. Which layer is responsible for error detection?

In OSI reference model data link layer performs error detection.

19. Which layer is responsible for error corrections?

In OSI reference model transport link layer performs error corrections.

Questions Based on IP address: 

1. What is an private IP address and there ranges?

There are three range of IP address have been reversed for private IP address and they are not valid for used on internet. If you want to access internet with these address you must have to use proxy server or NAT server. The range of private IP address are as followed for different class:  
Class A 10.0.0.0 10.255.255.255 
Class B 172.16.0.0 172.31.255.255 
Class C 192.168.0.0 192.168.255.255

2. What is an public IP address?

A public IP address is an address leased from an ISP that allows or enables direct Internet communication. Other than private IP addresses all are public IP address.

3. What is the subnet mask?

Like an IP address, a subnet mask is made up of an 32 bits. A subnet mask is combined with an IP address in order to identify two parts: the extended network address and the host address.

4. What is benefit of subnetting?

• Subnetting is the process of conversions of large network into small network.
• Easy troubleshooting.
• It reduce IP wastage in network.
• Reduce the size of the routing tables. 
• Reduce network traffic. Broadcast traffic can be isolated within a single logical network. 
• Provide a way to secure network traffic by isolating it from the rest of the network.

5. What is a IP?

It's a unique 32 bits software address of a node in a network.

6. What is the subnet mask of class A, Class B, Class C?

Class A: 255.0.0.0
Class B: 255.255.0.0
Class c: 255.255.255.0

7. What is the ranges of different classes?

Class A: 0-127
Class B: 128-191
Class c: 192-223
Class D: 224-239
Class E: 240-255

8. What is CIDR?

CIDR stands for classless inter domain routing. It is a value which represent of network bit in an IP address.

9. What is APIPA?

APIPA stands for Automatic Private IP Address. When DHCP is not enable to provide the IP address at that time APIPA will provide the IP address. And it range is 169.254.0.0-169.254.255.255.

10. What is used of loopback address?

The loopback address is used for to checking the self connectivity. and its range is 127.0.0.0-127.255.255.255.

11. What is PING?

PING stands for packet internet grouper. It is used for checking the connectivity.

12. What are the differences between static ip addressing and dynamic ip addressing?

With static IP addressing, a computer (or other device) is configured to always use the same IP address. With dynamic addressing, the IP address can change periodically and is managed by a centralized network service.

13. What is Tracert?

Tracert is a Windows utility program that can used to trace the route taken by data from the router to the destination network. It also shows the number of hops taken during the entire transmission route.

                       

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OSI reference model

OSI Reference Model

What is the simplest explanation of the OSI model involving real examples?

• OSI long from is open loop system interconnection.
• It is developed by International Standard Organization (ISO) in 1970.
• OSI reference model has 7 layers.
• Physical (layer 1), Data link (layer 2), Network (layer 3), Transport (layer 4), Session (layer 5), Presentation (layer 6), Application (layer 7).
• Below mention the functions that occur at each layer of the OSI model.

OSI reference model

Application layer:

• The application layer of the OSI model marks the spot where user actually communicate or interact with the computer.
• User application is in any form like file, print, images, messages, database, and application services.
• Data an application layer is in original from.

Presentation layer:

The Presentation layer gets its name from its purpose it present data to the application layer and is responsible for data translation and code formatting. A successful data transfer technique is to adapt the data into a standard format before transmission.

Computer are configured to receive this generically formatted data and then converted it back into its native format for reading for exam, from EBCDIC to ASCII. By providing translation services, the presentation layer ensures that the data transferred from one system. Application layer can be read and understood by application layer on another’s.
The OSI has protocol standards that define how the data should be formatted task like data compression, decompression, encryption, and decryption are all associated with this layer. Presentation layer standards are even involved in multimedia operation.

• Presentation layer perform data encryption at sender side and decryption done at receiving side .
• It is an user interface layer user can do compression of data at sender side and decompression was happened at receiver side.
• User can mange data in appropriate from.
• Data an presentation layer is in bit from.

Session layer:

The Session layer is responsible for setting up, managing, and then tearing down sessions between between presentation layer entities. This layer also provides dialog control between devices, or nodes. It coordinates communication between systems and servers to organize their communication by offering three different mods: simplex, half duplex, full duplex. To sum up, the session layer basically keeps applications data separate from other application data,

• Session layer perform flow control of data.
• Session layer provide session management.
• Session layer also mange header size.
• Session layer also main tented data and time user sending and receiving data.

Transport layer:

The Transport layer segments and reassembles data into stream. Services located in the transport layer handle from upper layer application and unite it onto the same data stream. They provide end to end data transport services and can establish a logical connection between the sending host and destination host on an internetwork,
The Transport layer the sending host for providing the mechanisms for multiplexing upper layer application, establishing virtual connections, and tearing down virtual circuits. It also hides the many and sundry details of any network dependent information from the higher layer facilitating data transfer.

• Transport layer convert the bit into segment.
• It assign the sequencing to the every segment.
• It also done port addressing.
• It perform connection management.
• UDP and TCP is used for connection management.

Network layer:

•  It routes the signal through different channels from one node to other.
•  It acts as a network controller. It manages the Subnet traffic.
•  It decides by which route data should take.
•  It divides the outgoing messages into packets and assembles the incoming packets into messages for higher levels.

Data link layer:

• Data link layer synchronizes the information which is to be transmitted over the physical layer.
• The main function of this layer is to make sure data transfer is error free from one node to another, over the physical layer.
•  Transmitting and receiving data frames sequentially is managed by this layer.
•  This layer sends and expects acknowledgements for frames received and sent respectively. Resending of non-acknowledgement received frames is also handled by this layer.
•  This layer establishes a logical layer between two nodes and also manages the Frame traffic control over the network. It signals the transmitting node to stop, when the frame buffers are full.

Physical layer:

•  Big picture of communication over network is understandable through this  OSI model.
•  We see how hardware and software work together.
•  We can understand new technologies as they are developed.
•  Troubleshooting is easier by separate networks.
•  Can be used to compare basic functional relationships on different networks.

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Types of WAN Connections

Types of WAN Connections

What is the types of WAN connections?

There are two main types of WAN connections.

• Dedicated Connection 
• Switched Connection

Types of WAN connection

Dedicated Connections

In computer networks and telecommunications, a dedicated line is a communications medium or other facility dedicated to a specific application, in contrast with a shared resource such as the telephone network or the Internet is called dedicated connection.

1.Leased Lines:

• It is a dedicated point to point connection which provides pre-establish WAN communication path through ISP to remote destination is called as leased line.
• It provide very high speed data transmission up to 64Gbps.
• It is very expensive.

2.Digital Subscriber Line (DSL):

• It is a provide connection between ISP to a customer through telephone line.
• It is a broadband technique which provides same upstream and downstream.

3. Asymmetric Digital Subscriber Line (ADSL): 

• Asymmetric digital subscriber line is type of digital subscriber line technology a data communication technology that enables faster data transmission over the copper telephone line rather than conventional voice modem used. 
• It is some like as digital subscriber line but only difference is that upstream and downstream are different. 

Switched Connections

There are three types of switched connection are as follows.

1. Circuit Switched Network.
2. Packet Switched Network.
3. Cell Switched Network.

1. Circuit Switched Network:

• In circuit switches network every time before transferring data over the WAN, new connection get establish after data transfer over the connection get closed.
• In this technique generally data is transferred through single connection or single route.

2. Packet Switched Network:

• In packet switched network uses virtual connection for transferring data, it for transferring data create connection on first data transmission and used it as a permanent connection.
• It is faster than circuit switched network.
• It is used for multi path communication.

3. Cell Switched Network: 

• In this type of network data transfer in fixed size cell that is 53 bytes.
• Its example as ATM.

      

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WAN Terminology

WAN Terminology

What is WAN Terminology?

WAN Terminology

1. Data Communication Equipment (DCE)

     This are the equipment which receive data from one device or transfer to another device is called data communication equipment.

 ex: Router, Bridge, Switches etc.

2. Data Terminal Equipment (DTE) 

   These are the device terminates the data communication is called as data terminal equipment.

  ex: End devices like router.

3. Customer Premises Equipment (CPE)

  These are the devices which are connected with customer premises is called customer premises equipment.

  ex: Bridge, Switches.

4. Channel Service Unit/Data Service Unit (CSU/DSU)

   It is used for digital line and used for modulation and demodulation is called channel service unit.

5. Demarcation Point

   It is boundary or boarder between customer premises equipment (CPE) and internet service provider (ISP) is called demarcation point.

6. Toll network

   It is also called as service provider network. When data exchange is done for multiple line is called toll network.

7. Local Loop

   It is interface or link used to connect channel service unit (CSU) and data service unit (DSU) to internet service provider is called local loop.

8. co switch (central office switch)

  This are switch used for exchanging data in toll network is called co switch.

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How do I use internet on mobile by cable modem?

How do I use internet on mobile by cable modem?

 Firstly you required router for wireless connection and then after follow this process.

• Connect the "WAN port" of your wireless router to the cable modem. Typically the router must be configured to get its IP address using DHCP, but this depends upon your cable provider. If you have trouble with this part, ask your cable company how to connect a broadband router to your cable modem.
• Connect the Wi-Fi card in your Fujitsu laptop to your wireless router using 802.11g. Follow instructions that came with your card and router -- typically you need to configure the same SSID (network name) and WEP keys in both the card and the router. When configuring WEP keys, watch out for differences between hex and ASCII. (Some products require keys to be entered in hex, others in ASCII, so be sure you follow instructions supplied with your card and router.) Try to connect the card without WEP enabled, then add WEP when the connection is working.
• Connect the desktop to the your wireless router. Most wireless routers have built-in 4-port Ethernet hubs which let you connect an Ethernet card in your desktop directly to the router. If your wireless router does not have any LAN Ethernet ports, or your desktop doesn't have an Ethernet card, then you'll need a Wi-Fi adapter for your desktop. Most people find it more convenient to use USB Wi-Fi adapters in desktops, Wi-Fi PCI cards are also an option.
• Most wireless routers default to give out LAN IP addresses with DHCP, so configure both the laptop and desktop to get IP addresses automatically from the router. Most wireless routers also default to using network address translation (NAT) to share one Internet connection across many WLAN stations, so you probably won't have to configure anything else in the router to make this all work.

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Comparison between RIP, EIGRP, IGRP, and OSPF

Comparison between RIP, EIGRP, IGRP, and OSPF

what is difference between RIP, EIGRP, IGRP and OSPF?

Sr.No	RIP	EIGRP	IGRP	OSPF
1	RIP Stands For Routing Information protocol.	EIGRP Stands For Enhanced Interior Gateway Routing protocol.	IGRP Stands For Interior Gateway Routing protocol.	OSPF stands For Open shortest path First.
2	It Is a Industry standard dynamic routing protocol.	It Is a Cisco standard routing protocol.	It is a Cisco standard routing protocol.	It Is a Industry standard routing protocol.
3	It is not a more intelligent dynamic routing protocol.	It Is a more intelligent routing protocol than RIP and IGRP.	It is a more intelligent routing protocol than RIP	It is a more intelligent routing protocol than RIP, IGRP and EIGRP.
4	It is basically use for smaller size organization.	It is basically use for medium to lager size organization in the network.	It is basically use for medium to larger size organization in the network.	It is basically use for larger size organization in the network
5	It support maximum 15 routers in the network. 16 router is unreachable	It supports maximum 255 routers in the network.	It supports maximum 255 routers in the network.	It supports unlimited router in the network
6	RIP is denoted by R in routing table.	EIGRP is denoted by D in routing table.	It Is denoted by I in routing table	It Is denoted by O in routing table
7	It’s Administrative Distance Is 120.	It’s Administrative distance Is 90.	It’s Administrative Distance Is 100.	It’s Administrative distance is 110.
8	In RIP routing protocol we cannot create a separate administrative boundary in the network.	In EIGRP routing protocol we can create a separate administrative boundary in the   network with the help of autonomous system No.	In IGRP routing protocol we can create a separate administrative boundary in the network with the help of autonomous System No.	In OSPF routing protocol we can create a separate administrative boundary in the network through area no. within the same area all of the routers are exchanging the route information from neighbor router in the network.
9	It calculates the metric In terms of Hop Count from source network to destination network. Lower the Hop count that is the best route for that particular network.	It calculates the metric In terms of bandwidth and delay.	It calculates the metric in terms of bandwidth and delay. It Is also called composite metric.	It calculates the metric in terms of bandwidth.
10	RIP  works on Bellman Ford algorithm.	EIGRP works on DUAL(Diffusing Update Algorithm) Algorithm.	IGRP works On Bellman ford Algorithm.	OSPF works on DIJKSTRA Algorithm.
11	RIPv1 Do Not Support VLSM. RIPv2 support VLSM.	EIGRP Supports VLSM.	IGRP do Not Support VLSM.	OSPF Supports VLSM.
12	RIP routing protocol creates two table in the router:     Routing Table ,Topology Table.	EIGRP routing protocol creates three table In the router :  Neighbor Table, Topology Table,  Routing Table.	IGRP routing protocol creates three table In the router :   Neighbor Table ,  Topology Table,   Routing Table.	OSPF routing protocol creates three Table in the router:   Neighbor Table, Database Table ,  Routing Table.

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