QUESTION BANK FOR COMPUTER NETWORKS (2140709)

1.   Explain any two application layer protocol.
2.   Explain WWW and HTTP.
3.   What is E-mail? How it works? Which protocol it uses?
4.  Explain the architectural overview of the World Wide Web.
5.  Explain Client side world wide web and server side world web.
6.  Describe the Built in HTTP request method.
7.   Explain the basic function of E-mail.
8.  Explain MIME.
9.   Explain the Domain Name system.
10.  Explain the Domain Resource Records.
11.  Explain socket Programming.
12. Explain Client and server communication in brief.
13.    Explain Implementation of Connection-Oriented Services.
14.  Explain Virtual Circuit Network.
15.  What is Datagram? Explain Datagram Network.
16.  Virtual Circuit Vs Datagram Networks.
17.  Describe Router. / Explain in detail Router.
18.  What is Switching Fabric?
19.  What is routing?
20.  Explain Distance Vector Routing.
21.  Explain link state routing with all the five steps in detail.
22.  Write about OSPF. Which four classes of routers are distinguished by OSPF?
23.  Explain in detail OSPF.
24.  Explain Spanning tree routing.
25.  What is Flooding?
26.  Explain the Mobile-IP./ write short notes on mobile IP.
27.  Explain and compare distance vector routing and link state routing algorithm.
28.  Explain the leaky bucket algorithm.
29.  Explain token bucket algorithm.
30.  Explain the congestion control in datagram subnets. Write about hop by hop choke packets scheme.
31.  Explain load shedding and jitter control strategies to handle the congestion.
32.  Explain the term jitter.
33.  Explain IP addressing scheme in detail.
34.  Compare the IPv4 and IPv6 Header.
35.  Explain the following concept:1)   Tunneling 2) Network Address Translation 3)DHCP
36. Write a note on ICMP.

Program to demonstrate Hybrid Inheritance.

Program:
#include<iostream.h>
#include<conio.h>
class student
{
int r_no;
public:
void get(int a)
{
r_no=a;
}
void put()
{
 cout<<"Rollnumber : "<<r_no<<endl;
 }
 };
 class test : virtual public student
 {
  protected :
  float s1,s2;
  public:
  void getmarks(float x,float y)
  {
   s1=x;
   s2=y;
   }
   void putmarks()
   {
    cout<<" Marks in Academics  "<<endl;
     cout<<" Marks in subject 1 : "<<s1<<endl;
      cout<<" Marks in subject 2 :  "<<s2<<endl;
      }
      };
      class sports :virtual public student
      {
       protected :
       float score;
       public:
       void getscore(float s)
       {
score=s;
}
void putscore()
{
 cout<<"Sports score is : "<<score<<endl;
 }
 };
 class result : public test, public sports
 {
 float total;
 public:
 void display()
 {
  total= ((s1+s2+score)/3);
  put();
  putmarks();
  putscore();
  cout<<"Result : " <<total <<endl;
  }};
  int main()
  {
  clrscr();
   result r;
   r.get(01);
   r.getmarks(89,95);
   r.getscore(100);
   r.display();
   getch();
   return 0;
   }

Write a program to demonstrate Hierarchical Inheritance.

Program :
#include<iostream.h>
#include<conio.h>
class m
{
 public :
  int m,n;
  public :
  void getmn(int x,int y)
  {
     m=x;
     n=y;
      }
  };
  class o : public m
  {
    public :
   void add(void)
   {
   cout<<"M= "<<m<<endl;
      cout<<"N= "<<n<<endl;
      cout<<"M+N= "<<m+n<<endl;


     }
   };
   class p : public m
   {
    public :
     void mul()
     {
      cout<<"M= "<<m<<endl;
      cout<<"N= "<<n<<endl;
      cout<<"M*N= "<<m*n<<endl;
      }
     };

    int main()
    {
    clrscr();
      p ob;
      o ob1;
      ob1.getmn(10,20);
      ob.getmn(30,20);
      ob1.add();
      ob.mul();

      getch();
      return 0;
      }

INTER PROCESS COMMUNICATION PROBLEMS

Classical IPC Problems:

1. Dining Philosophers Problem

2. The Readers and Writers Problem

3. The Sleeping Barber Problem

1.    Dining philosophers problems:

There are N philosphers sitting around a circular table eating spaghetti and discussing philosphy. The problem is that each philosopher needs 2 forks to eat, and there are only N forks, one between each 2 philosophers. Design an algorithm that the philosophers can follow that insures that none starves as long as each philosopher eventually stops eating, and such that the maximum number of philosophers can eat at once.

·       Philosophers eat/think

·        Eating needs 2 forks

·        Pick one fork at a time

·        How to prevent deadlock

The problem was designed to illustrate the problem of avoiding deadlock, a   system state in which no progress is possible.

One idea is to instruct each philosopher to behave as follows:

·       think until the left fork is available; when it is, pick it up

·        think until the right fork is available; when it is, pick it up

·        eat

·        put the left fork down

·        put the right fork down

·        repeat from the start.

This solution is incorrect: it allows the system to reach deadlock. Suppose that all five philosophers take their left forks simultaneously. None will be able to take their right forks, and there will be a deadlock.

We could modify the program so that after taking the left fork, the program checks to see if the right fork is available. If it is not, the philosopher puts down the left one, waits for some time, and then repeats the whole process. This proposal too, fails, although for a different reason. With a little bit of bad luck, all the philosophers could start the algorithm simultaneously, picking up their left forks, seeing that their right forks were not available, putting down their left forks, waiting, picking up their left forks again simultaneously, and so on, forever. A situation like this, in which all the programs continue to run indefinitely but fail to make any progress is called starvation.

The solution presented below is deadlock-free and allows the maximum parallelism for an arbitrary number of philosophers. It uses an array, state, to keep track of whether a philosopher is eating, thinking, or hungry (trying to acquire forks). A philosopher may move into eating state only if neither neighbor is eating. Philosopher i's neighbors are defined by the macros LEFT and RIGHT. In other words, if i is 2, LEFT is 1 and RIGHT is 3.

  Solution:  

#define N            5             /* number of philosophers */

 #define LEFT         (i+N-1)%N     /* number of i's left neighbor */

 #define RIGHT        (i+1)%N       /* number of i's right neighbor */

 #define THINKING     0             /* philosopher is thinking */

 #define HUNGRY       1             /* philosopher is trying to get forks */

#define EATING       2             /* philosopher is eating */

 typedef int semaphore;             /* semaphores are a special kind of int */

 int state[N];                      /* array to keep track of everyone's state */

semaphore mutex =1;               /* mutual exclusion for critical regions */

semaphore s[N];                    /* one semaphore per philosopher */

 void philosopher(int i)            /* i: philosopher number, from 0 to N1 */

{   

 while (TRUE)

  {                                         /* repeat forever */  

   think();                   /* philosopher is thinking */      

   take_forks(i);               /* acquire two forks or block */   

   eat();                   /* yum-yum, spaghetti */  

put_forks(i);            /* put both forks back on table */    

}

}

void take_forks(int i)             /* i: philosopher number, from 0 to N1 */

{    

down(&mutex);                 /* enter critical region */    

state[i] = HUNGRY;            /* record fact that philosopher i is hungry */   

 test(i);                      /* try to acquire 2 forks */    

up(&mutex);                   /* exit critical region */   

down(&s[i]);                  /* block if forks were not acquired */

}

void put_forks(i)                  /* i: philosopher number, from 0 to N1 */

{    

down(&mutex);                 /* enter critical region */    

state[i] = THINKING;          /* philosopher has finished eating */

     test(LEFT);                   /* see if left neighbor can now eat */    

test(RIGHT);                  /* see if right neighbor can now eat */   

 up(&mutex);                   /* exit critical region */

}

void test(i)                       /* i: philosopher number, from 0 to N1* /

{    

if (state[i] == HUNGRY && state[LEFT] != EATING && state[RIGHT] != EATING)

{          

state[i] = EATING;         

 up(&s[i]);   

 }

}

Readers Writer problems:

The dining philosopher’s problem is useful for modeling processes that are competing for exclusive access to a limited number of resources, such as I/O devices. Another famous problem is the readers and writers problem which models access to a database (Courtois et al., 1971). Imagine, for example, an airline reservation system, with many competing processes wishing to read and write it. It is acceptable to have multiple processes reading the database at the same time, but if one process is updating (writing) the database, no other process may have access to the database, not even a reader. The question is how do you program the readers and the writers?

One solution is shown below.

Solution to Readers Writer problems

typedef int semaphore;                  /* use your imagination */

semaphore mutex = 1;                    /* controls access to 'rc' */

semaphore db = 1;                       /* controls access to the database */

int rc = 0;                             /* # of processes reading or wanting to */

void reader(void)

{    

while (TRUE)

{                      /* repeat forever */          

down(&mutex);                /* get exclusive access to 'rc' */          

rc = rc + 1;                 /* one reader more now */         

 if (rc == 1) down(&db);      /* if this is the first reader ... */         

 up(&mutex);                  /* release exclusive access to 'rc' */         

 read_data_base();            /* access the data */         

 down(&mutex);                /* get exclusive access to 'rc' */         

 rc = rc  1;                 /* one reader fewer now */         

 if (rc == 0) up(&db);        /* if this is the last reader ... */         

 up(&mutex);                  /* release exclusive access to 'rc' */         

 use_data_read();             /* noncritical region */    

}

}

void writer(void)

{  

  while (TRUE)

{                      /* repeat forever */       

  think_up_data();              /* noncritical region */       

  down(&db);                    /* get exclusive access */       

  write_data_base();            /* update the data */       

  up(&db);                      /* release exclusive access */    

}

}

In this solution, the first reader to get access to the data base does a down on the semaphore db. Subsequent readers merely have to increment a counter, rc. As readers leave, they decrement the counter and the last one out does an up on the semaphore, allowing a blocked writer, if there is one, to get in.

NUMERICAL AND STATISTICAL  METHODS FOR COMPUTER ENGINEERING

                                                   SUBJECT CODE :2140706

  GTU WINTER 2015 SOLVED PAPER

SOLUTION OF NSM DOWNLOAD HERE

GTU IMPORTANT QUESTIONS

Question Bank

Subject: Digital Electronics        Semester: 3^rd

 1.     Describe hexadecimal number system. Explain conversion between decimal number system  and hexadecimal number system.

 2.     Sums of conversion from one number system to other number system(Especially  pay more attention to floating point numbers) and other sums.

 3.     Explain 1’s and 2’s complements with suitable examples. Show the subtraction using complements.

4.     Explain excess-3 code. Show addition in Excess-3 code with suitable examples.

 5. Explain BCD codes with suitable example. Show addition in BCD code

                            (Add (275 + 496) in BCD).

6. What is Gray code? What are its applications?

7. Explain in brief ASCII code, Weighted binary code, EBCDIC code ?

 8. Explain following terms or Explain important parameters of Digital IC ?

9. Explain NAND and NOR as a Universal gate?

 10. Explain Saturated and Non-Saturated Logic ? Give names of Saturated and Non-Saturated Logic families?

11. Explain Positive and Negative logic system?

 12.Draw symbol, truth table, and write Boolean expression for all the gates?

13. Discuss characteristics of TTL family.

 14. Draw and explain working of  TTL NAND Gate Circuit? What is the main advantage of TTL TOTEM Pole Output?

15. Explain CMOS NAND gate?

 16.State and Prove Demorgan’s Law.

17. State Properties of Boolean Algebra.

 18. Draw logic circuit from given Boolean Expression and vice versa?

19. Sums of Karnaugh Map ( especially 4 variable K-map ) ( SOP and POS both)

 20. Sums of Simplification of Boolean Expression, Prove the given Boolean expression, Find SOP and POS, Canonical SOP and POS for given function.

21.Compare Half Adder and Full Adder.

 22.Design Half Adder circuit using NOR gates only.

23. Explain Full Adder and draw logic circuit for full adder using only NAND gates?

 24. Explain Full Subtractor and draw logic circuit for full subtractor using A-O-I gates?

25. What is parity? Explain parity checker/generator and state its application?

 26.Explain BCD Adder?

27. Explain circuit diagram of parallel binary adder.

28. Draw and explain circuit diagram of 4-bit Binary Parallel Adder/Subtractor. 

 29. Draw and explain binary to gray code convertor and gray to binary code convertor?

30.Explain multiplexer and its state its applications. Show the difference between multiplexer and decoder.

 31.Explain 4 to 16 line decoder? Draw its circuit using NAND gates.

32.Write short note on BCD to seven segment decoder.

 33.Difference between Combinational  and Sequential circuits?

34. Write short notes on following

 35. Explain J-K master slave flip flop with logic diagram.

36. Explain the terms Asynchronous and Synchronous?

 37.Conversion of one flip flop in to another flip flop.

38.Explain  the positive and Negative edge triggering and Level Triggering.

 39. Draw circuit diagram of serial input serial output shift register. Draw waveforms to shift 1010 in to the register.

 40. What is shift register? What are the applications of shift register? Explain 4 bit parallel in parallel out shift register.

41. Explain serial in parallel out shift register with neat diagram.

 42.Explain the universal shift register.

43.Classify the different types of memory.

 44.What is advantage of EEPROM over EPROM? Explain EPROM and state its applications.

45. Give difference between RAM and ROM.

GTU IMPORTANT QUESTIONS

ENGINEERING PHYSICS(2110011)

       

Q-1	Explain the characteristics of musical sound.
Q-2.	Discuss various factors affecting acoustics of building & give their remedies.
Q-3.	Discuss the principle & method of producing ultrasonic waves by magnetostriction method.
Q-4.	Discuss the principle & method of producing ultrasonic waves by piezoelectric method.
Q-5.	Explain the acoustics grating method of determining the velocity of ultrasonic waves in liquids.
Q-6.	Describe the construction & working of Nd: YAG laser with a suitable energy level diagram.
Q-7.	Difference between stimulated emission & spontaneous emission
Q-8	What do you mean by acceptance angle & numerical aperture? Derive expression for them.
Q-9	List out the difference between single mode fibre & multimode fibre.
Q-10	Explain the mode of propagation of optical fiber & index profile.
Q-11	Explain meissner effect & prove that χ = -1 for superconductors.
Q-12.	Difference between type-I & type-II superconductors
Q-13	Explain any one high temperature superconducting oxide.
Q-14	Explain melt spinning technique to prepare metallic glasses.
Q-15.	Explain functional properties (i) shape memory effect (ii) superelasticity.
Q-16.	Explain (1) The pulse echo system and (2) ultrasonic flaw detector with advantages & limitations.
Q-17	What is nanoparticle? Explain size dependence effect in nanomaterial
Q-18.	Discuss in detail  (1) the quantum confinement (2) surface to volume ratio
Q-19	Explain the synthesis method of nano-material (1) Ball Milling (2) Sol-gel Explain the properties, application and  types of carbon nanotube
Q-20	What is Noise pollution? Explain how to control noise in machine.
Q-21	Discuss briefly about sound absorbing materials.
Q-22	The primary advantages of fibre-optics communication compared to metallic cable communication.
Q-23	Explain soft & hard magnetic materials.
Q-24	Explain hysteresis B - H curve
Q-25	Explain general properties of ferromagnetic materials & paramagnetic materials.
Q-26	Explain ferrites.
Q-27	Derive Clausius – mossotti Equation
Q-28	Explain types of Dielectric material
Q-30	Explain Electrical polarisation mechanism.