MCQ Review of MST-III

              MCQ's                           

Questions	Answer
1Q) In link state routing, after the construction of link state packets new routes are computed using ..................... (A) Bellman Ford algorithm (B) DES algorithm (C) Dijkstra's algorithm (D) Leaky bucket algorithm	C
2Q) Count-to-Infinity problem occurs in ..................... (A) distance vector routing (B) short path first (C) link state routing (D) hierarchical routing	A
3Q) In distance vector routing the delay metric is ................... (A) number of hops (B) geographical distance (C) number of neighbours (D) queue length	D
4Q) In which routing method do all the routers have a common database? (A) Distance Vector (B) Link Vector (C) Shortest path D) Link State	D
5Q) SSL divides data into blocks of (A) 2*6 (B) 2*14 (C) 2*20 (D) 2*24	B
6Q) We also don't want our undeliverable packets to hop around forever. What feature/flag limits the life of an IP packet on the network? (A) Time to Live counter (B)Subnet Mask (C) Header Checksum (D) Wackamole Field	A
7Q). Pretty good privacy (PGP) is used in (A) Browser security (B) Email security (C) FTP security (D) None	B
8Q) IPSec is designed to provide the security at the (A) Transport layer (B) Network layer (C) Application layer (D) Session layer	B

Notice regarding MST3

Your MST 3 will be conducted on Monday (25/4/2016) after 2 PM. Venue NR3

Syllabus

Routing Algorithms
The Optimality Principle, Shortest Path Routing, Flooding, Distance Vector Routing, Link State Routing, Hierarchical Routing, Broadcast Routing, Multicast Routing,

Internetwork Protocols
Internet Protocol & IP Addresses, Principles of Internetworking, Internet Protocol Operation, IPv6, Virtual Private Networks and IP Security

MCQ's Answer of MST-I

MCQ's Answer of MST-I

SET-A

Questions	Answer
1Q) Application layer is implemented in a) End system b) NIC c) Ethernet d) None of the mentioned	A
2Q) Delimiting and synchronization of data exchange is provided by a) Application layer b) Session layer c) Transport layer d) Link layer	B
3Q) To join the internet, the computer has to be connected to a a) internet architecture board b) internet society c) internet service provider d) none of the mentioned	C
4Q) Physical or logical arrangement of network is a) Topology b) Routing c) Networking d) None of the mentioned	A
5)Q: Coaxial cable consists of _______ concentric copper conductors. a) 1 b) 2 c) 3 d) 4	B
6Q) Radio channels are attractive medium because a) Can penetrate walls b) Connectivity can be given to mobile user c) Can carry signals for long distance d) All of the mentioned	D
7Q) TCP/IP model was developed _____ the OSI model. a) prior to b) after c) simultaneous to d) none of the mentioned	A
8Q) Switch is used in which layer? a) Application layer b) Session layer c) Transport layer d) None of the above	D

SET-B

Questions	Answer
1Q) Transmission data rate is decided by a) network layer b) physical layer c) data link layer d) transport layer	B
2Q) Which one of the following task is not done by data link layer? a) framing b) error control c) flow control d) channel coding	D
3Q) The network layer concerns with a) bits b) frames c) packets d) none of the mentioned	C
4Q) Hub is used in which layer? a) Application layer b) Session layer c) Physical layer d) Link layer	C
5Q) Data Encryption is used in which layer? a) Application layer b) Session layer c) Transport layer d) None of above	D
6Q) Which address identifies a process on a host? a) physical address b) logical address c) port address d) specific address	C
7Q) A _____ is a device that forwards packets between networks by processing the routing information included in the packet. a) bridge b) firewall c) router d) all of the mentioned	C
8Q) 2. Which transmission media has the highest transmission speed in a network? a) coaxial cable b) twisted pair cable c) electrical cable d) optical fiber	D

MCQ's Answer of MST-II

MCQ's Answer of MST-II

Questions	Answer
1Q) In virtual circuit network each packet contains a) full source and destination address b) a short VC number c) both (a) and (b) d) none of the mentioned	b
2Q) A Virtual-Circuit Network (VCN) is normally implemented in the a)session layer b)data link layer c) network layer d) physical layer	b
3Q) Global and local addressing are types of a)WAN network b)local area circuit network c)virtual-circuit network d)MAN network	c
4Q) There is no communication between the congested node or nodes and the source in the a) Implicit Signaling b) IP Signaling c) Source Signaling d)Data Signaling	a
5Q) In Congestion, traffic descriptors are qualitative values that represent a a)Data Protocol b)Data Flow c) Data Congestion d) Data Traffic	b
6Q) __ happens in any system that involves waiting. a) Congestion b) Jamming c) Error d) none of the above	a
7Q) For applications such as audio and video streaming, the variation in the packet arrival times is called ................. (a) Random early detection (b) Jitter c) Delay difference (d) Load shedding	b
8Q) Congestion in a network or internetwork occurs because routers and switches have a) tables b) queues c) crosspoints d) none of the above	b

Assignment # 3-4

Assignments#3

1Q: Write down a  note on Congestion control in Packet Switching networks.
2Q: Write a note on Routing in Ad hoc Networks.
3Q: What is Node Lookup in Peer-to-Peer Networks.

Assignment#4

1Q: Congestion Control in Datagram Subnets and Virtual Circuit?
2Q: What is Principle of inter-networking?
3Q: Write a note on IPV6?



Last Date: 3/4/2015

Congestion

Click on following link,

Congestion

Tutorial Sheet# 3&4

Tutorial#3

1. In virtual circuit network each packet contains
a) full source and destination address
b) a short VC number
c) both (a) and (b)
d) none of the mentioned

2. Multidestination routing
a) is same as broadcast routing
b) contains the list of all destinations
c) data is not sent by packets
d) none of the mentioned

3. A subset of a network that includes all the routers but contains no loops is called

a) spanning tree
b) spider structure
c) spider tree
d) none of the mentioned

4. The routing processor searches the routing table is called

a) switch fabric

b) buffer

c) table lookup

d) rolling table

5. A Virtual-Circuit Network (VCN) is normally implemented in the

a)session layer

b)data link layer

c) network layer

d) physical layer

6. What is packet filter?

7. What is multi cast routing?

Tutorial#4

1Q: Which frame completes the entries in the switching tables

a) acknowledgement frame

b) setup frame

c)routing frame

d)None

2Q: In a packet-switched network, resources are allocated

a) randomly

b) on demand

c) reserved already

d)both a and c

3Q: Datagram switching is done at the

a)network layer

b) physical layer

c)session layer

d)data link layer

4Q: The identifier that is actually used for data transfer is called the

a) virtual-circuit identifier

b) global address

c) local address

d)header

5Q: Global and local addressing are types of

a)WAN network

b)local area circuit network

c)virtual-circuit network

d)MAN network

6Q:What is region?

7Q: What is Bit Stuffing?

Tude will be check on upcoming tutorial day

Assignment#2

Assignment#2

Date of issue: 23/02/2016

Date of Submission: 29/02/2016

1Q: What is Framing ? Explain its types with example.

2Q: Write a note on HDLC with proper frame format.

3Q: Give description of network devices.

Tutorial No 1 & 2

Tutorial No.1

1Q) Two devices are in network if
a) a process in one device is able to exchange information with a process in another device
b) a process is running on both devices
c) PIDs of the processes running of different devices are same
d) none of the mentioned

2Q) Which one of the following computer network is built on the top of another network?
a) prior network
b) chief network
c) prime network
d) overlay network

3Q) In computer network nodes are
a) the computer that originates the data
b) the computer that routes the data
c) the computer that terminates the data
d) all of the mentioned

4Q) How will you test LAN card?

5Q) Which command is used to check the IP address of your system?

Tutorial No.2

1Q) A list of protocols used by a system, one protocol per layer, is called
a) protocol architecture
b) protocol stack
c) protocol suit
d) none of the mentioned

2Q) Which one of the following extends a private network across public networks?
a) local area network
b) virtual private network
c) enterprise private network
d) storage area network

3Q) Communication channel is shared by all the machines on the network in
a) broadcast network
b) uni cast network
c) multi cast network
d) none of the mentioned

4Q) Bluetooth is an example of
a) personal area network
b) local area network
c) virtual private network
d) none of the mentioned

5Q) Which command is used to check the physical connectivity between two computers?

Submit both the assignment on your upcoming tude. Use A4 paper sheet. 

OSI Reference Model:

OSI reference model is a logical framework for standards for the network communication. OSI reference model is now considered as a primary standard for internetworking and inter computing. Today many network communication protocols are based on the standards of OSI model. In the OSI model the network/data communication is defined into seven layers. 

To remember the names of seven layers in order one common mnemonic used is -"All People Seem to Need Data Processing". i.e

All- Application

People-Presentation

Seem- Session

To- Transport

Need- Network

Data- Data Link

Processing- Physical.

Application Layer:

The application layer serves as the window for users and application processes to access network services. The application layer makes the interface between the program that is sending or is receiving data and the protocol stack.

Functions of Application  layer:

·         Resource sharing and device redirection.

·         Remote file access.

·         Remote printer access.

·         Inter-process communication.

·         Network management.

·         Directory services.

·         Electronic messaging (such as mail).

Presentation Layer

Presentation Layer is also called Translation layer. The presentation layer presents the data into a uniform format and masks the difference of data format between two dissimilar systems.

Functions of Presentation Layer:

·         Character code translation: for example, ASCII to EBCDIC.

·         Data conversion: bit order, CR-CR/LF, integer-floating point, and so on.

·         Data compression: reduces the number of bits that need to be transmitted on the network.

·         Data encryption: encrypt data for security purposes. For example, password encryption.

Session Layers:

Session layer has the primary responsibility of beginning, maintaining and ending the communication between two devices, which is called Session. It also provides for orderly communication between devices by regulating the flow of data.

The examples of session layers and the interactive logins.

Functions of Session Layer:

·          Session establishment, maintenance and termination.

·       Session support: performs the functions that allow these processes to communicate over the network, performing security, name recognition, logging and so on.

·      Dialog control: Dialog control is the function of session layer that determines which device will communicate first and the amount of data that will be sent.

·   Dialog separation or Synchronization: The session layer is also responsible for adding checkpoint or markers within the message. This process of inserting markers to the stream of data is known as dialog separation.

·    Protocols: The protocols that work on the session layer are NetBIOS, Mail Slots, Names Pipes, and RPC.

Transport Layer:

Transport layer manages end to end (source to destination) (process to process) message delivery in a network and also provides the error checking and hence guarantees that no duplication or errors are occurring in the data transfers across the network. It makes sure that all the packets of a message arrive intact and in order.

Functions of Transport Layer:

·         Segmentation of message into packet and reassembly of packets into message:

·         Message acknowledgment

·         Message traffic control

·         Session multiplexing

·         Service point addressing

·         Flow control

Network Layer:

This layer is in charge of packet addressing, converting logical addresses into physical addresses. It is responsible for the source-to-destination delivery of a packet across multiple networks (links). This layer is also in charge of setting the routing. The packets will use to arrive at their destination, based on factors like traffic and priorities. The network layer determines that how data transmits between the network devices.

Functions of Network Layer:

·        Subnet Traffic Control: Routers (network layer intermediate systems) can instruct a sending station to "throttle back" its frame transmission when the router's buffer fills up.

·         Logical-Physical Address Mapping

·         Subnet Usage Accounting

·         Internetworking

·         Logical Addressing

·         Routing

·         Packetizing

·         Fragmentation

      

Data Link Layer:

It is responsible for reliable node-to-node delivery of data. It receives the data from network layer and creates frames, add physical address to these frames and pass them to physical layer

The data link layer provides error-free transfer of data frames from one node to another over the physical layer, allowing layers above it to assume virtually error-free transmission over the link.

Functions of Data Link Layer:

·         Link Establishment and Termination

·         Physical addressing

·         Frame Traffic Control

·         Frame Sequencing

·         Frame Acknowledgment

·         Frame Error Checking: 

·         Media Access Management

·         Flow control 

·         Error control 

·         Access control 

Physical Layer:

The physical layer, the lowest layer of the OSI model, is concerned with the transmission and reception of the unstructured raw bit stream over a physical medium. It describes the electrical/optical, mechanical, and functional interfaces to the physical medium, and carries the signals for all of the higher layers. Physical layer defines the cables, network cards and physical aspects.

Functions of Physical Layer:

·         Data Encoding: 

·         Transmission Technique:

·         Physical Medium

·         Protocols : ISDN, IEEE 802 and IEEE 802.2.

·         Bit synchronization

·         Provides physical characteristics of interfaces and medium

·         Bit rate control

·         Line configuration

·         Transmission mode

·         Physical topologies

·         Multiplexing

·         Circuit switching

Why Layering?

·         Divide a task into pieces and then solve each piece independently (or nearly so).

·         Establishing a well defined interface between layers  makes porting easier.

·         Functions of each layer are independent of functions of other layers

• Thus each layer is like a module and can be developed independently

·         Each layer builds on services provided by lower layers

• Thus no need to worry about details of lower layers -- transparent to this layer

Major Advantages

n  Code Reuse

n  Eases maintenance, updating of system

TCP/IP

TCP/ IP stands for Transmission Control Protocol/ Internet Protocol. If this leads you to think that it is not just one protocol, you’re right. In fact, it is not just two protocols, either. TCP/ IP is a suite of protocols.

TCP/IP is a family of protocols. A few provide "low- level" functions needed for many applications. These include IP, TCP, and UDP. Others are protocols for doing specific tasks, e.g. transferring files between computers, sending mail, or finding out who is logged in on another computer. Initially TCP/IP was used mostly between minicomputers or mainframes. These machines had their own disks, and generally were self contained.

 

Application Layer

The application layer is provided by the program that uses TCP/IP for communication. An application is a user process cooperating with another process usually on a different host (there is also a benefit to application communication within a single host). Examples of applications include Telnet and the File Transfer Protocol (FTP).

The Process Layer contains protocols that implement user-level functions, such as mail delivery, file transfer and remote login.

Transport Layer

The transport layer provides the end-to-end data transfer by delivering data from an application to its remote peer. Multiple applications can be supported simultaneously. The most-used transport layer protocol is the Transmission Control Protocol (TCP), which provides connection-oriented reliable data delivery, duplicate data suppression, congestion control, and flow control.

Another transport layer protocol is the User Datagram Protocol It provides connectionless, unreliable, best-effort service. As a result, applications using UDP as the transport protocol have to provide their own end-to-end integrity, flow control, and congestion control, if desired. Usually, UDP is used by applications that need a fast transport mechanism and can tolerate the loss of some data.

 

Internetwork Layer

The internetwork layer also called the internet layer or the network layer, provides the “virtual network” image of an internet this layer shields the higher levels from the physical network architecture below it. Internet Protocol (IP) is the most important protocol in this layer. It is a connectionless protocol that does not assume reliability from lower layers. IP does not provide reliability, flow control, or error recovery.

 These functions must be provided at a higher level. IP provides a routing function that attempts to deliver transmitted messages to their destination. A message unit in an IP network is called an IP datagram. 

This is the basic unit of information transmitted across TCP/IP networks. Other internetwork-layer protocols are IP, ICMP, IGMP, ARP, and RARP.

 

Host to network(PL n DLL)

The network interface layer, also called the link layer or the data-link layer or Host to Network Layer, is the interface to the actual network hardware. This interface may or may not provide reliable delivery, and may be packet or stream oriented.

In fact, TCP/IP does not specify any protocol here, but can use almost any network interface available, which illustrates the flexibility of the IP layer. Examples are IEEE 802.2, X.25,ATM, FDDI, and even SNA.TCP/IP specifications do not describe or standardize any network-layer protocols, they only standardize ways of accessing those protocols from the internet work layer.

Difference between OSI and TCP model.

OSI(Open System Interconnection)	TCP/IP(Transmission Control Protocol / Internet Protocol)
1. OSI provides layer functioning and also defines functions of all the layers.	1. TCP/IP model is more based on protocols and protocols are not flexible with other layers.
2. In OSI model the transport layer guarantees the delivery of packets	2. In TCP/IP model the transport layer does not guarantees delivery of packets.
3. Follows horizontal approach	3. Follows vertical approach.
4. OSI model has a separate presentation layer	4. TCP/IP does not have a separate presentation layer
5. OSI is a general model.	5. TCP/IP model cannot be used in any other application.
6. Network layer of OSI model provide both connection oriented and connectionless service.	6. The Network layer in TCP/IP model provides connectionless service.
7. OSI model has a problem of fitting the protocols in the model	7. TCP/IP model does not fit any protocol
8. Protocols are hidden in OSI model and are easily replaced as the technology changes.	8. In TCP/IP replacing protocol is not easy.
9. OSI model defines services, interfaces and protocols very clearly and makes clear distinction between them.	9. In TCP/IP it is not clearly separated its services, interfaces and protocols.
10. It has 7 layers	10. It has 4 layers