Go Back N - Sender & Receiver

1. Go Back N Sender:

import java.io.*; import java.net.*; import java.lang.*; public class gbnsend { public static void main(String args[]) { int serverport=3333; String address="127.0.0.2"; try { InetAddress ipaddress=InetAddress.getByName(address); Socket socket=new Socket(ipaddress,serverport); InputStream sin=socket.getInputStream(); OutputStream sout=socket.getOutputStream(); DataInputStream in=new DataInputStream(sin); DataOutputStream out=new DataOutputStream(sout); BufferedReader keyboard=new BufferedReader(new InputStreamReader(System.in)); String line=null; String word []=new String [8]; int i; System.out.println("plz input the no of frames to b sent"); int n=Integer.parseInt(keyboard.readLine()); for(i=0;i<n;i++) { word[i]=keyboard.readLine(); } i=0; while(i<n) { System.out.println("sending frame "+word[i]); out.writeUTF(word[i]); out.flush(); i++; } try { Thread.sleep(1000); } catch(InterruptedException e) { e.printStackTrace(); } line=in.readUTF(); System.out.println("nack received for frame "+line); i=Integer.parseInt(line); out.writeUTF(word[i]); System.out.println("retransmitting all frames after "+word[i]); i++; while(i<n) { System.out.println("sending frame "+word[i]); out.writeUTF(word[i]); out.flush(); i++; } } catch(Exception e) { e.printStackTrace(); } } }

2. Go Back N Receiver:

import java.net.*; import java.io.*; public class gbnreceive { public static void main(String args[]) { int port=3333; try { ServerSocket ss=new ServerSocket(port); System.out.println("waiting for user2"); Socket socket=ss.accept(); System.out.println("user detected"); System.out.println(); InputStream sin=socket.getInputStream(); OutputStream sout=socket.getOutputStream(); DataInputStream in=new DataInputStream(sin); DataOutputStream out=new DataOutputStream(sout); BufferedReader keyboard=new BufferedReader(new InputStreamReader(System.in)); String line=null; String word []=new String [8]; int i=0; while(i<4) { line=in.readUTF(); word[i]=line; System.out.println("frame "+word[i]+" received successfully"); i++; } while(i<8) { if(i==4) { System.out.println("frame "+i+" not received"); i++; } else { System.out.println("frame "+i+" discarded"); i++; } } System.out.println("requesting for retransmaission"); line=keyboard.readLine(); out.writeUTF(line); out.flush(); i=4; while(i<8) { line=in.readUTF(); word[i]=line; i++; } System.out.println("received all retransmitted frames successfully"); } catch(Exception e) { e.printStackTrace(); } /*finally { sin.close(); sout.close(); in.close(); out.close(); }*/ } }

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Anonymous 7:20 am  No comment

Infix to Postfix Conversion

Following is the java code for converting from infix to postfix:

// To convert Infix into Postfix import java.io.*; class infix2 { public static void main(String args[]) throws IOException { check obj=new check(); String str = new String(); char infix[]=new char[15]; char postfix[]=new char[15]; char stack[]=new char[15]; int len=0,i=0,j=0,top=-1,value; BufferedReader b=new BufferedReader(new InputStreamReader(System.in)); System.out.println("Enter Expression ==> "); str=b.readLine(); len=str.length(); infix=str.toCharArray(); for(i=0;i<=len-1;i++) { int t=obj.isoperand(infix[i]); if(t==1) { postfix[j]=infix[i]; j++; } else if(top==-1) { top++; stack[top]=infix[i]; } else if(infix[i]==')') { while(stack[top]!='(') { postfix[j]=stack[top]; top--; j++; } top--; } else if(obj.priority(infix[i])>obj.priority(stack[top])) { top++; stack[top]=infix[i]; } else { if(obj.priority(infix[i])==obj.priority(stack[top])) { postfix[j]=stack[top]; top--; j++; } else { while(obj.priority(infix[i])<obj.priority(stack[top]) && top!=-1 && stack[top]!='(') { postfix[j]=stack[top]; top--; j++; } } top++; stack[top]=infix[i]; } } //end of for loop while(top!=-1) { postfix[j]=stack[top]; top--; j++; } System.out.println("The Postfix Expression is"); for(i=0;i<len;i++) System.out.print(postfix[i]); }//end of main }//end of class class check { int isoperand(char ch) { if((ch>='A' && ch<='Z' )|| (ch>='a' && ch<='z')) return 1; else return 0; }//end of isoperand method int priority(char ch) { if(ch=='(') return 4; if(ch=='^' || ch=='%') return 3; if(ch=='*' || ch=='/') return 2; if(ch=='+' || ch=='-') return 1; if(ch==')') return 0; return -1; }//end of priority method }//end of class check

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Anonymous 8:15 am  No comment

Packet Sniffer

ACN Packet Sniffer

Our sir told to use some packetsniffer other than Wireshark or Colasoft. So I used Smartsniff.
Click the link below for snapshots
SmartSniff

For snapshots of Wireshark click the link below
Wireshark

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Anonymous 7:38 pm  No comment

Apriori Algorihm

Apriori Algorithm:

#include<stdio.h> #include<conio.h> int item[5][5]={{1,3,4,6},{2,3,5,7},{1,2,3,5,8},{2,5,9,10},{1,4}}; int fn(int a,int b); int main() { int tid[5]={1,2,3,4,5} ,i,j,ms,k,count[11]={0}; int p,a,b,c; printf("\n\tTrans_id\t\tItems\n\n"); for(i=0;i<5;i++) { printf("\t%d \t\t\t",tid[i]); for(j=0;j<5;j++) { if(item[i][j]!=0) printf("%d",item[i][j]); } printf("\n"); } printf("\n Assume minimum support:"); scanf("%d",&ms); for(k=1;k<=10;k++) { for(i=0;i<5;i++) for(j=0;j<5;j++) if(item[i][j]==k&&item[i][j]!=0) count[k]++; } printf("\nGenerating c1 from the data"); for(k=1;k<=10;k++) printf("\n\t\t%d\t\t%d",k,count[k]); for(k=1;k<=10;k++) { if(count[k]<ms) count[k]=0; } printf("\nGenerating l1 from c1"); for(k=1;k<=10;k++) { a=2; if(count[k]!=0) printf("\n\t\t%d\t\t%d",k,count[k]); } printf("\nGenerating l2 from c2"); p=2; b=3; for(i=1;i<4;i++) { for(j=p++;j<=5;j++) { if(fn(i,j)>=ms) printf("\n\t\t%d%d\t\t%d",i,j,fn(i,j)); c=5; } } printf("\n\t\tGenerating l3"); printf("\n\n\t\t\t\t%d %d %d",a,b,c); getch(); return 0; } int fn(int a,int b) { int i,j,cnt=0,aa,flag=0; for(i=0;i<5;i++) { flag=0; for(j=0;j<5;j++) { aa=j; if(flag==1) goto ab; if(a==item[i][j]) { flag=1; j++; ab: if(b==item[i][j]) { cnt++; break; } } j=aa; } } return cnt; } /************OUTPUT*********** Trans_id Items 1 1346 2 2357 3 12358 4 25910 5 14 Assume minimum support:2 Generating c1 from the data 1 3 2 3 3 3 4 2 5 3 6 1 7 1 8 1 9 1 10 1 Generating l1 from c1 1 3 2 3 3 3 4 2 5 3 Generating l2 from c2 13 2 14 2 23 2 25 3 35 2 Generating l3 2 3 5*/

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Anonymous 7:28 pm  No comment

Computer Graphics programs in C++

The term computer graphics includes almost everything on computers that is not text or sound. Today almost every computer can do some graphics, and people have even come to expect to control their computer through icons and pictures rather than just by typing.

Here in our lab at the Program of Computer Graphics, we think of computer graphics as drawing pictures on computers, also called rendering. The pictures can be photographs, drawings, movies, or simulations -- pictures of things which do not yet exist and maybe could never exist. Or they may be pictures from places we cannot see directly, such as medical images from inside your body.

Computer graphics are graphics created using computers and the representation of image data by a computer specifically with help from specialized graphic hardware and software.

The interaction and understanding of computers and interpretation of data has been made easier because of computer graphics. Computer graphic development has had a significant impact on many types of media and have revolutionized animation, movies and the video game industry.

CG Programs
Most of the prog have been included.
click on the link below to download
CGprog

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Anonymous 1:04 pm  No comment

Jigsaw puzzle

Jigsaw puzzle html
Download the Jigzaw puzzle from the download box alongside.

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Anonymous 12:57 pm  No comment

Economic Crisis 2008 Seminar Presentation

This is the Seminar Presentation that we prepared for the Economic Crisis that started in 2008

Economic Crisis 2008

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Anonymous 12:55 pm  No comment

Sudoku puzzle in javascript

Download the Code for Sudoku puzzle for 3X3, 6X6, & 9X9 from the download box alongside.

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Anonymous 12:46 pm  No comment

Computer Graphics mini project/ Screen Saver code

1. Car Screensaver:

/******************************************************************* Program : Screensaver: Moving car ********************************************************************/ #include<iostream.h> #include"conio.h" #include<math.h> #include"stdlib.h" #include"dos.h" #include"graphics.h" #define DELAY 1 #define SOUND 3500 void state(int x,int y,int mode); int area,area1; void *ptr1,*ptr2,*burst; void BF(int,int,int,int); void circ_bre(int x,int y,int rad); void draw_burst ( int x, int y,int ); void display(int,int,int,int); void dda(int x1,int y1,int x2,int y2); int COND(int x,int y) { if (x>20 && x<getmaxx()-20 && y>20 && y<getmaxy()-20) return 1; else return 0; } void state(int x,int y,int mode) { while(COND(x,y)&&!kbhit()) { if(x==300&&y==230) { putimage(350,230,burst,COPY_PUT); sound(SOUND); delay(100); cleardevice(); state(30,30,0); } switch(mode) { case 0: // x++; putimage(getmaxx()-x,getmaxy()-y,ptr1,COPY_PUT); // delay(1); putimage(x,y,ptr2,COPY_PUT); // putimage(getmaxx()-x,getmaxy()-y,ptr1,XOR_PUT); // putimage(x,y,ptr2,COPY_PUT); // delay(3); //putimage(x,y,ptr2,XOR_PUT); x++; break; case 1: // x--; // putimage(getmaxx()-x,getmaxy()-y,ptr2,COPY_PUT); // delay(1); putimage(x,y,ptr1,COPY_PUT); putimage(getmaxx()-x,getmaxy()-y,ptr2,COPY_PUT); //putimage(x,y,ptr1,COPY_PUT); //delay(3); //putimage(x,y,ptr1,XOR_PUT); x--; break; case 2: putimage(getmaxx()-x,getmaxy()-y,ptr1,COPY_PUT); //delay(3); putimage(x,y,ptr2,COPY_PUT); //putimage(getmaxx()-x,getmaxy()-y,ptr1,XOR_PUT); //putimage(x,y,ptr2,COPY_PUT); //delay(3); //putimage(x,y,ptr2,XOR_PUT); x--; break; case 3: putimage(getmaxx()-x,getmaxy()-y,ptr2,COPY_PUT); //delay(3); putimage(x,y,ptr1,COPY_PUT); //putimage(getmaxx()-x,getmaxy()-y,ptr2,XOR_PUT); //putimage(x,y,ptr1,COPY_PUT); // delay(3); //putimage(x,y,ptr1,XOR_PUT); x++; break; } // delay(0); nosound(); } cleardevice(); if(y>=getmaxy()-20||y<=20) { sound(SOUND); switch(mode) { case 0: state(++x,y=y-20,2); break; case 1: state(++x,y=y+20,3); break; case 2: state(++x,y=y+20,1); break; case 3: state(++x,y=y+20,0); break; } } if(x>=(getmaxx()-20)||x<=20) { sound(SOUND); switch(mode) { case 0: state(--x,y=y+20,1); break; case 1: state(++x,y=y+20,0); break; case 2: state(--x,y=y-20,3); break; case 3: state(++x,y=y-20,2); break; } } } void main() { int gd = DETECT, gm; /*detect the graphics drivers automatically*/ initgraph(&gd,&gm,"\tc\tc\bgi"); /*Initialise to graphics mode*/ //int area; cleardevice(); // setbkcolor(); //CAR 1 dda(60,70,60,85); dda(60,70,80,75); dda(60,70,90,70); dda(80,75,80,90); dda(60,85,80,90); dda(80,75,110,75); dda(90,70,110,75); dda(90,70,110,55); dda(110,55,130,60); dda(110,75,130,60); dda(80,90,90,90); dda(110,90,160,90); dda(180,90,190,90); dda(190,75,190,90); dda(170,60,190,75); dda(130,60,170,60); dda(150,55,170,60); dda(110,55,150,55); dda(117,73,132,62); dda(132,62,168,62); dda(117,73,183,73); dda(168,62,183,73); dda(150,62,150,73); circ_bre(100,90,10); circ_bre(170,90,10); // BF(70,90,15,12); area=imagesize(59,55,191,100); ptr1=malloc(area); // setcolor(3); // floodfill(70,80,15); getimage(59,55,191,100,ptr1); cleardevice(); //CAR 2 dda(60,75,60,90); dda(60,75,80,60); dda(80,60,120,60); dda(80,60,100,55); dda(100,55,140,55); dda(120,60,140,55); dda(120,60,140,75); dda(140,55,160,70); dda(140,75,160,70); dda(160,70,190,70); dda(170,75,190,70); dda(140,75,170,75); dda(190,70,190,85); dda(170,90,190,85); dda(170,75,170,90); circ_bre(150,90,10); circ_bre(80,90,10); dda(160,90,170,90); dda(90,90,140,90); dda(60,90,70,90); dda(118,62,137,75); dda(80,62,118,62); dda(64,75,80,62); dda(64,75,137,75); dda(100,62,100,75); area=imagesize(59,55,190,100); ptr2=malloc(area); getimage(59,55,191,100,ptr2); cleardevice(); draw_burst(200,300,area1); cleardevice(); state(30,30,0); getch(); closegraph(); } void dda(int x1,int y1,int x2,int y2) { int i,dx,dy,steps; float x,y; float xinc,yinc; dx = (x2-x1); dy = (y2-y1); if(abs(dx)>=abs(dy)) /* decide whether to move along x-direction */ steps = dx; /* or y-direction */ else steps = dy; xinc =(float) dx/steps; /*calculate the increment value for x & y*/ yinc =(float) dy/steps; x = x1; y = y1; putpixel (x,y,RED); /* plot first point */ for (i=1;i<steps;i++) { x = x + xinc; y = y + yinc; /* convert the floating value to its nearest interger value. i.e. same as use of floor or ceil function */ x1 = x + 0.5 ; y1 = y + 0.5 ; putpixel (x1,y1,RED); /* plot the points */ } } void circ_bre(int x,int y,int rad) { float dp; //initialising the descision parameter. int x1,y1; x1 = 0; //initialisng the X,Y cordinates. y1 = rad; dp = 3 - 2*rad; while(x1<=y1) { if(dp<=0) dp += (4 * x1) + 6; else { dp += 4*(x1-y1)+10; y1--; } x1++; display(x1,y1,x,y); } } void display (int x1,int y1,int x,int y) { putpixel(x1+x,y1+y,WHITE); //plotting the pixels. putpixel(x1+x,y-y1,WHITE); putpixel(x-x1,y1+y,WHITE); putpixel(x-x1,y-y1,WHITE); putpixel(x+y1,y+x1,WHITE); putpixel(x+y1,y-x1,WHITE); putpixel(x-y1,y+x1,WHITE); putpixel(x-y1,y-x1,WHITE); } /*void BF(int x,int y,int bc,int fc) {if(getpixel(x,y)!=bc&&getpixel(x,y)!=fc) {putpixel(x,y,fc); BF(x+1,y,bc,fc); BF(x+1,y-1,bc,fc); BF(x,y-1,bc,fc); BF(x-1,y-1,bc,fc); BF(x-1,y,bc,fc); BF(x-1,y+1,bc,fc); BF(x,y+1,bc,fc); BF(x+1,y+1,bc,fc); } } */ void draw_burst ( int x, int y,int area ) { // setlinestyle(0,0,1); line ( x - 16, y - 12, x - 10, y - 2 ) ; line ( x - 10, y - 2, x - 16, y ) ; line ( x - 16, y, x - 10, y + 2 ) ; line ( x - 10, y + 2, x - 16, y + 12 ) ; line ( x - 16, y + 12, x - 6, y + 2 ) ; line ( x - 6, y + 2, x, y + 12 ) ; line ( x, y + 12, x + 6, y + 2 ) ; line ( x + 6, y + 2, x + 16, y + 12 ) ; line ( x - 16, y - 12, x - 6, y - 2 ) ; line ( x - 6, y - 2, x, y - 12 ) ; line ( x, y - 12, x + 6, y - 2 ) ; line ( x + 6, y - 2, x + 16, y - 12 ) ; line ( x + 16, y - 12, x + 10, y - 2 ) ; line ( x + 10, y - 2, x + 16, y ) ; line ( x + 16, y, x + 10, y + 2 ) ; line ( x + 10, y + 2, x + 16, y + 12 ) ; area=imagesize(0,0,32,24); burst=malloc(area); getimage(200-16,300-12,200+16,300+12,burst); // putimage(200-16,300-12,200+16,300+12,burst); cleardevice(); // putimage(200-16,300-12,200+16,300+12,burst); }

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Anonymous 11:18 am  No comment

Packet garbage and analysis using Wireshark

On the Internet, packet filtering is the process of passing or blocking packets at a network interface based on source and destination addresses, ports, or protocols. The process is used in conjunction with packet mangling and Network Address Translation (NAT). Packet filtering is often part of a firewall program for protecting a local network from unwanted intrusion.

In a software firewall, packet filtering is done by a program called a packet filter. The packet filter examines the header of each packet based on a specific set of rules, and on that basis, decides to prevent it from passing (called DROP) or allow it to pass (called ACCEPT).

There are three ways in which a packet filter can be configured, once the set of filtering rules has been defined. In the first method, the filter accepts only those packets that it is certain are safe, dropping all others. This is the most secure mode, but it can cause inconvenience if legitimate packets are inadvertently dropped. In the second method, the filter drops only the packets that it is certain are unsafe, accepting all others. This mode is the least secure, but is causes less inconvenience, particularly in casual Web browsing. In the third method, if the filter encounters a packet for which its rules do not provide instructions, that packet can be quarantined, or the user can be specifically queried concerning what should be done with it. This can be inconvenient if it causes numerous dialog boxes to appear, for example, during Web browsing.

Wireshark is a network packet analyzer. A network packet analyzer will try to capture network packets and tries to display that packet data as detailed as possible.

You could think of a network packet analyzer as a measuring device used to examine what's going on inside a network cable, just like a voltmeter is used by an electrician to examine what's going on inside an electric cable (but at a higher level, of course).

Here are some examples people use Wireshark for:

• network administrators use it to troubleshoot network problems
• network security engineers use it to examine security problems
• developers use it to debug protocol implementations
• people use it to learn network protocol internals

Download the manual from the download box alongside.

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Anonymous 8:22 am  No comment

Optimism Vs Pessimism

Is Your Glass Half Full or Half Empty?

Are you a glass half full or a glass half empty kind of person? Does it really make a difference? I think it makes a huge difference in the quality of your life. Both optimists and pessimists contribute to our society.  The optimist invents the airplane and the pessimist the parachute. Two men look out through the same bars: One sees the mud, & one the stars.

Optimism can lead to accomplishment. If you think something is possible, you will generally work harder to achieve it. Believing in the positive allows you to feel good about life in general. The average pencil is seven inches long, with just a half-inch eraser. Being optimistic can lead to an overall mood of happiness, and enjoyment in life. While most optimists understand that not everything works out as planned, they recognize that some good can come from the unexpected.

Pessimism can lead to defeat and despair. A pessimist is a man who looks both ways before crossing a one way street. When you are doubtful about your success, you tend not to try as hard - which then leads to failure. A pessimist is somebody who complains about the noise when opportunity knocks. Approaching everyday tasks with a negative attitude quickly leads to a negative outlook on life.

I don’t think many cases of eyestrain have been developed by looking on the bright side of things. I think it is this positive upbeat attitude that allows us to be productive and love the work we do. I truly believe that our optimistic attitude is what provides us with our sense of fulfillment, and improves our overall quality of life.

Between the optimist and the pessimist, the difference is droll. The optimist sees the doughnut; the pessimist the hole! Winston Churchill once said, “The pessimist sees difficulty in every opportunity. The optimist sees the opportunity in every difficulty”.

We all have moments of optimism and pessimism; what it comes down to is how the scale is tipped. Is your cup half full or half empty? One should realize that when it is dark enough, you can see the stars.

So from here on, when you face any challenge in life just say

“I'm not afraid of storms, for I'm learning how to sail my ship.”

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Anonymous 8:09 pm  No comment