CN LAB

EX. NO: 1.a TCP SOCKETS

DATE: TCP ECHO SERVER / CLIENT

AIM:

To implement echo client server using TCP/IP

ALGORITHM

Server

1. Create a server socket and bind it to port.

2. Listen for new connection and when a connection arrives, accept it.

3. Read the data from client.

4. Echo the data back to the client.

5. Repeat steps 4-5 until bye or null is read.

6. Close all streams.

7. Close the server socket.

8. Stop.

Client

1. Create a client socket and connect it to the servers port number.

2. Get input from user.

3. If equal to bye or null, then go to step 7.

4. Send user data to the server.

5. Display the data echoed by the server.

6. Repeat steps 2-4.

7. Close the input and output streams.

8. Close the client socket.

9. Stop.

PROGRAM:

// TCP Echo Server--tcpechoserver.java

import java.net.*;

import java.io.*;

public class tcpechoserver

{

public static void main(String[] arg) throws IOException

{

ServerSocket sock = null;

BufferedReader fromClient = null;

OutputStreamWriter toClient = null;

Socket client = null;

try

{

sock = new ServerSocket(4000); System.out.println("Server Ready");

client = sock.accept(); System.out.println("Client Connected");

fromClient = new BufferedReader(new

InputStreamReader(client.getInputStream()));

toClient = new OutputStreamWriter(client.getOutputStream());

String line;

while (true)

{

line = fromClient.readLine();

if ( (line == null) || line.equals("bye"))

break;

System.out.println ("Client [ " + line + " ]");

toClient.write("Server [ "+ line +" ]\n");

toClient.flush();

}

fromClient.close();

toClient.close();

client.close();

sock.close();

System.out.println("Client Disconnected");

}

catch (IOException ioe)

{

System.err.println(ioe);

}

}

}

//TCP Echo Client--tcpechoclient.java

import java.net.*;

import java.io.*;

public class tcpechoclient

{

public static void main(String[] args) throws IOException

{

BufferedReader fromServer = null, fromUser = null;

PrintWriter toServer = null;

Socket sock = null;

try

{

if (args.length == 0)

sock = new Socket(InetAddress.getLocalHost(),4000);

else

sock = new Socket(InetAddress.getByName(args[0]),4000);

fromServer = new BufferedReader(new

InputStreamReader(sock.getInputStream()));

fromUser = new BufferedReader(new InputStreamReader(System.in));

toServer = new PrintWriter(sock.getOutputStream(),true);

String Usrmsg, Srvmsg;

System.out.println("Type \"bye\" to quit");

while (true)

{

System.out.print("Enter msg to server : ");

Usrmsg = fromUser.readLine();

if (Usrmsg==null || Usrmsg.equals("bye"))

{

toServer.println("bye"); break;

}

else

toServer.println(Usrmsg);

Srvmsg = fromServer.readLine();

System.out.println(Srvmsg);

}

fromUser.close();

fromServer.close();

toServer.close();

sock.close();

}

catch (IOException ioe)

{

System.err.println(ioe);

}

OUTPUT

Server:

$ javac tcpechoserver.java

$ java tcpechoserver

Server Ready Client Connected Client [ hello ]

Client [ how are you ] Client [ i am fine ] Client [ ok ]

Client Disconnected

Client :

$ javac tcpechoclient.java

$ java tcpechoclient

Type "bye" to quit

Enter msg to server : hello

Server [ hello ]

Enter msg to server : how are you

Server [ how are you ]

Enter msg to server : i am fine

Server [ i am fine ]

Enter msg to server : ok

Server [ ok ]

Enter msg to server : bye

RESULT

Thus data from client to server is echoed back to the client to check reliability/noise level

of the channel.

EX. NO: 1.b TCP SOCKETS DATE AND TIME SERVER / CLIENT

DATE:

AIM:

To implement date and time display from client to server using TCP Sockets

ALGORITHM:

Server

1. Create a server socket and bind it to port.

2. Listen for new connection and when a connection arrives, accept it.

3. Send servers date and time to the client.

4. Read clients IP address sent by the client.

5. Display the client details.

6. Repeat steps 2-5 until the server is terminated.

7. Close all streams.

8. Close the server socket.

9. Stop.

Client

1. Create a client socket and connect it to the servers port number.

2. Retrieve its own IP address using built-in function.

3. Send its address to the server.

4. Display the date & time sent by the server.

5. Close the input and output streams.

6. Close the client socket.

7. Stop.

PROGRAM:

//TCP Date Server--tcpdateserver.java

import java.net.*;

import java.io.*;

import java.util.*;

class tcpdateserver

{

public static void main(String arg[])

{

ServerSocket ss = null;

Socket cs;

PrintStream ps;

BufferedReader dis;

String inet;

try

{ ss = new ServerSocket(4444);

System.out.println("Press Ctrl+C to quit");

while(true)

{

cs = ss.accept();

ps = new PrintStream(cs.getOutputStream());

Date d = new Date();

ps.println(d);

dis = new BufferedReader(new

InputStreamReader(cs.getInputStream()));

inet = dis.readLine();

System.out.println("Client System/IP address is :"+ inet);

ps.close();

dis.close();

}

}

catch(IOException e)

{

System.out.println("The exception is :" + e);

}

}

}

//TCP Date Client--tcpdateclient.java

import java.net.*;

import java.io.*;

class tcpdateclient

{

public static void main (String args[])

{

Socket soc;

BufferedReader dis;

String sdate;

PrintStream ps;

try

{

InetAddress ia = InetAddress.getLocalHost();


soc = new Socket(InetAddress.getLocalHost(),4444);

else

soc = new Socket(InetAddress.getByName(args[0]),4444);

dis = new BufferedReader(new

InputStreamReader(soc.getInputStream()));

sdate=dis.readLine();

System.out.println("The date/time on server is : " +sdate);

ps = new PrintStream(soc.getOutputStream());

ps.println(ia);

ps.close(); catch(IOException e)

{

System.out.println("THE EXCEPTION is :" + e);

} } }

OUTPUT

Server:

$ javac tcpdateserver.java

$ java tcpdateserver

Press Ctrl+C to quit

Client System/IP address is : localhost.localdomain/127.0.0.1

Client System/IP address is : localhost.localdomain/127.0.0.1

Client:

$ javac tcpdateclient.java

$ java tcpdateclient

The date/time on server is: Wed Feb 06 07:12:03 GMT 2015

RESULT:

Thus the program for implementing to display date and time from client to server using

TCP Sockets was executed successfully and output verified using various samples.

EX. NO: 1.c TCP CHAT SERVER / CLIENT

DATE:

AIM

To implement a chat server and client in java using TCP sockets.

ALGORITHM

Server

1. Create a server socket

2. Wait for client to be connected.

3. Read Client's message and display it

4. Get a message from user and send it to client

5. Repeat steps 3-4 until the client sends "end"

6. Close all streams

7. Close the server and client socket

8. Stop

Client

1. Create a client socket and establish connection with the server

2. Get a message from user and send it to server

3. Read server's response and display it

4. Repeat steps 2-3 until chat is terminated with "end" message

5. Close all input/output streams

6. Close the client socket

7. Stop

PROGRAM

// TCP Chat Server--tcpchatserver.java

import java.io.*;

import java.net.*;

class tcpchatserver

{

public static void main(String args[])throws Exception

{

PrintWriter toClient;

BufferedReader fromUser, fromClient;

try

{

ServerSocket Srv = new ServerSocket(5555);

System.out.print("\nServer started\n");

Socket Clt = Srv.accept();

System.out.println("Client connected");

toClient = new PrintWriter(new BufferedWriter(new

OutputStreamWriter(Clt.getOutputStream())), true);


InputStreamReader(Clt.getInputStream()));

fromUser = new BufferedReader(new

InputStreamReader(System.in));

String CltMsg, SrvMsg;

while(true)

{

CltMsg= fromClient.readLine();

if(CltMsg.equals("end"))

break;

else

{

System.out.println("\nServer

System.out.println(E.getMessage());

}

}

}

// TCP Chat Server--tcpchatserver.java

import java.io.*;

import java.net.*;

class tcpchatserver

{


{

PrintWriter toClient;

BufferedReader fromUser, fromClient;

try

{

ServerSocket Srv = new ServerSocket(5555);

System.out.print("\nServer started\n");

Socket Clt = Srv.accept();

System.out.println("Client connected");

toClient = new PrintWriter(new BufferedWriter(new

OutputStreamWriter(Clt.getOutputStream())), true);



fromUser = new BufferedReader(new



while(true)

{

CltMsg= fromClient.readLine();

if(CltMsg.equals("end"))

break;

else

{

System.out.println("\nServer

Srv.close();

}

catch (Exception E)

{


}

}

}

OUTPUT

Server Console

$ javac tcpchatserver.java

$ java tcpchatserver

Server started

Client connected

Server

EX.NO:1. d TCP FILE SERVER/CLIENT

DATE:

AIM

To implement a file server / client in java using TCP sockets.

ALGORITHM

Server

1. Check given directory name for file server. If not given, then assume current directory.


3. Wait for client to be connected.

4. Get filename to be sent from the Client. If filename is invalid then quit.

5. Get a message from user and send it to client

6. Open the file and wirte file contents line-by-line onto output stream.

7. If end-of-file is encountered then close all streams

8. Close the sockets

9. Stop

Client

1. Create a client socket and establish connection with the server

2. Get filename from user and send it to server.

3. Read file contents line-by-line on input stream and display it

4. When a null is encountered during read, close all streams


6. Stop

PROGRAM

// TCP File Server -- FileServer.java

import java.io.*;

import java.net.*;

public class FileServer

{

public static void main(String[] args) throws Exception

{

File dir;

ServerSocket ss;

Socket conn;

BufferedReader br;

PrintWriter pw;

if(args.length == 0)

dir = new File("./");

else

dir = new File(args[0]);

if(!dir.exists() || !dir.isDirectory())

{

System.out.println("Directory does not exist");

System.exit(-1);

}

try

{

ss = new ServerSocket(3210);

conn = ss.accept();

br = new BufferedReader(new

InputStreamReader(conn.getInputStream()));

pw = new PrintWriter(conn.getOutputStream());

String name = br.readLine().trim();

File F = new File(dir, name);

if((!F.exists()) || F.isDirectory())

pw.println("File does not exists");

else

{

pw.println("\n");

BufferedReader fin = new BufferedReader(new

FileReader(F));

while(true)

{

String line = fin.readLine();

if(line == null)

break;

pw.println(line);

}

System.out.println("File Transferred\n");

}

pw.flush();

pw.close();

}

catch(Exception e) {

System.out.println("Error: " + e);

}

}

}

// TCP File Client -- FileClient.java

import java.io.*;

import java.net.*;

class FileClient

{


{

try

{

Socket Clt;


Clt = new Socket(InetAddress.getLocalHost(),

3210);

else

Clt = new

Socket(InetAddress.getByName(args[0]),3210);

PrintWriter OS =new PrintWriter(new

BufferedWriter(new OutputStreamWriter(Clt.getOutputStream())),

true);

BufferedReader IS = new BufferedReader(new


BufferedReader br = new BufferedReader(new



System.out.print("\nFilename : ");

CltMsg = br.readLine();

OS.println(CltMsg);

while ((SrvMsg = IS.readLine()) != null)

System.out.println(SrvMsg);

}

catch(Exception E) {


}

}

}

OUTPUT

Server Console

$ javac FileServer.java

$ java FileServer

File Transferred

Client Console

$ javac FileClient.java

$ java FileClient

Filename : hello.java

import java.io.*;

class hello

{

public static void main(String args[])

{

System.out.println("hello");

}

}

RESULT

Thus server transmits a file over the network using TCP socket programming

PRE LAB (10) POST LAB (10) VIVA (10) TOTAL (30) TOT (10)

EX.NO: 2.a UDP SOCKETS

DATE: UDP ECHO SERVER/CLIENT

AIM

To implement echo server and client in java using UDP sockets.

ALGORITHM

Server

1. Create a datagram socket

2. Receive client's message in a datagram packet.

3. Read Client's message and display it

4. Convert text from client to upper case and send it back to client

5. Repeat steps 2-4 until the client has something to send

6. Close the server socket

7. Stop

Client


2. Get a message from user

3. Construct a datagram packet and send it to server

4. Create a datagram packet to receive echoed message


6. Repeat steps 2-5 until there is some text to send


8. Stop

PROGRAM

// UDPEchoServer

import java.net.*;

class UDPEchoServer

{

public static void main(String args[]) throws Exception

{

DatagramSocket SrvSoc = new DatagramSocket(7777);

byte[] SData = new byte[1024];

System.out.println("Server Ready\n");

while (true)

{

byte[] RData = new byte[1024];

DatagramPacket RPack = new DatagramPacket(RData,RData.length);

SrvSoc.receive(RPack);

String Text = new String(RPack.getData());

if (Text.trim().length() > 0)

{

System.out.println("From Client


IPAddr = InetAddress.getLocalHost();

else

IPAddr = InetAddress.getByName(args[0]);


System.out.println("To quit, press enter without text");

while (true)

{

System.out.print("\nEnter text for Server : ");

Text = br.readLine();

SData = Text.getBytes();

DatagramPacket SPack = new DatagramPacket(SData,SData.length, IPAddr, 7777);

CliSoc.send(SPack);

if (Text.trim().length() == 0)

break;



CliSoc.receive(RPack);

String Echo = new String(RPack.getData()) ;

Echo = Echo.trim();

System.out.println("Echo from Server

OUTPUT

Server Console

$ javac UDPEchoServer.java

$ java UDPEchoServer

Server Ready

From Client

EX.NO: 2.b UDP CHAT SERVER/CLIENT

DATE:

AIM

To implement a chat server and client in java using UDP sockets.

ALGORITHM

Server

1. Create two ports, server port and client port

2. Create a datagram socket and bind it to client port

3. Create a datagram packet to receive client message

4. Wait for client's data and accept it.

5. Read Client's message

6. Get data from user

7. Construct a datagram packet and send message through server port

8. Repeat steps 3-7 until the client has something to send


10. Stop

Client

1. Create two ports, server port and client port

2. Create a datagram socket and bind it to server port

3. Get data from user

4. Create a datagram packet and send data with server ip address and client port

5. Create a datagram packet to receive server message


7. Repeat steps 3-6 until there is some text to send


9. Stop

PROGRAM

// udpchatserver

import java.io.*;

import java.net.*;

class udpchatserver

{

public static void main(String args[]) throws Exception

{

DatagramSocket SrvSoc = new DatagramSocket(5555);


BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

System.out.println("Server Ready");

while (true)

{



SrvSoc.receive(RPack);

String Text = new String(RPack.getData());


break;

System.out.println("\nFrom Client

InetAddress IPAddr;

String Text;


IPAddr = InetAddress.getLocalHost();

else

IPAddr = InetAddress.getByName(args[0]);


System.out.println("Press Enter without text to quit");

while (true)

{

System.out.print("\nEnter text for server : ");

Text = br.readLine();

SData = Text.getBytes();

DatagramPacket SPack = new DatagramPacket(SData,SData.length, IPAddr, 5555);

CliSoc.send(SPack);


break;



CliSoc.receive(RPack);

String Echo = new String(RPack.getData()) ;

Echo = Echo.trim();

System.out.println("From Server

OUTPUT

Server Console

$ javac udpchatserver.java

$ java udpchatserver

Server Ready

From Client

EX.NO: 2.c UDP DNS SERVER/CLIENT

DATE:

AIM

To implement a DNS server and client in java using UDP sockets.

ALGORITHM

Server

1. Define an array of hosts and its corresponding IP address in another array


3. Create a datagram packet to receive client request

4. Read the domain name from client to be resolved

5. Lookup the host array for the domain name

6. If found then retrieve corresponding address

7. Construct a datagram packet to send response back to the client

8. Repeat steps 3-7 to resolve further requests from clients


10. Stop

Client


2. Get domain name from user

3. Construct a datagram packet to send domain name to the server

4. Create a datagram packet to receive server message

5. If it contains IP address then display it, else display "Domain does not exist"


7. Stop

PROGRAM

// udpdnsserver.java

import java.io.*;

import java.net.*;

public class udpdnsserver

{

private static int indexOf(String[] array, String str)

{

str = str.trim();

for (int i=0; i < array.length; i++)

{

if (array[i].equals(str))

return i;

}

return -1;

}

public static void main(String arg[])throws IOException

{

String[] hosts = {"yahoo.com", "gmail.com",

"cricinfo.com", "facebook.com"};

String[] ip = {"68.180.206.184", "209.85.148.19",

"80.168.92.140", "69.63.189.16"};

System.out.println("Press Ctrl + C to Quit");

while (true)

{

DatagramSocket serversocket=new DatagramSocket(1362);

byte[] senddata = new byte[1021];

byte[] receivedata = new byte[1021];

DatagramPacket recvpack = new

DatagramPacket(receivedata, receivedata.length);

serversocket.receive(recvpack);

String sen = new String(recvpack.getData());

InetAddress ipaddress = recvpack.getAddress();

int port = recvpack.getPort();

String capsent;

System.out.println("Request for host " + sen);

if(indexOf (hosts, sen) != -1)

capsent = ip[indexOf (hosts, sen)];

else

capsent = "Host Not Found";

senddata = capsent.getBytes();

DatagramPacket pack = new DatagramPacket(senddata,

senddata.length,ipaddress,port);

serversocket.send(pack);

serversocket.close();

}

}}

// udpdnsclient

import java.io.*;

import java.net.*;

public class udpdnsclient

{

public static void main(String args[])throws IOException

{


DatagramSocket clientsocket = new DatagramSocket();

InetAddress ipaddress;


ipaddress = InetAddress.getLocalHost();

else

ipaddress = InetAddress.getByName(args[0]);

byte[] senddata = new byte[1024];

byte[] receivedata = new byte[1024];

int portaddr = 1362;

System.out.print("Enter the hostname : ");

String sentence = br.readLine();

senddata = sentence.getBytes();

DatagramPacket pack = new DatagramPacket(senddata,senddata.length, ipaddress,portaddr);

clientsocket.send(pack);

DatagramPacket recvpack =new DatagramPacket(receivedata,receivedata.length);

clientsocket.receive(recvpack);

String modified = new String(recvpack.getData());

System.out.println("IP Address: " + modified);

clientsocket.close();

}

}

OUTPUT

Server Console

$ javac udpdnsserver.java

$ java udpdnsserver

Press Ctrl + C to Quit

Request for host yahoo.com

Request for host cricinfo.com

Request for host youtube.com

Client Console

$ javac udpdnsclient.java

$ java udpdnsclient

Enter the hostname : yahoo.com

IP Address: 68.180.206.184

$ java udpdnsclient

Enter the hostname : cricinfo.com

IP Address: 80.168.92.140

$ java udpdnsclient

Enter the hostname : youtube.com

IP Address: Host Not Found

RESULT

Thus domain name requests by the client are resolved into their respective logical address

using lookup method.


RAW SOCKETS

EX.NO: 3 PACKET CAPTURE

AIM

To sniff and parse packets that pass through using raw sockets.

ALGORITHM

1. Set the ethernet interface in promiscuous mode to sniff all packets

2. Create a raw socket with Ethernet-to-IP protocol.

3. Bind socket to the Ethernet interface using bind()

4. Get the number of packets to be sniffed from the user.

5. When a proper packet arrives, receive it using recvfrom()

6. Print the entire packet contents in hexadecimal using a loop.

7. Parse the packet

a. Print source and destination MAC addresss from Ethernet header

b. Print source and destination IP address from IP header

c. If the transport layer protocol is TCP, then print the source and destination port from TCP

header

d. If the packet contains data then print the data

8. Repeat steps 57 until required number of packets are sniffed

9. Stop

PROGRAM

//Packet Sniffing sniffdata.c

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

int CreateRawSocket(int protocol_to_sniff)

{

int rawsock;

if((rawsock = socket(PF_PACKET, SOCK_RAW,htons(protocol_to_sniff)))== -1)

{

perror("Error creating raw socket: ");

exit(-1);

}

return rawsock;

}

int BindRawSocketToInterface(char *device, int rawsock, int protocol)

{

struct sockaddr_ll sll;

struct ifreq ifr;

bzero(&sll, sizeof(sll));

bzero(&ifr, sizeof(ifr));

/* Get Interface Index */

strncpy((char *)ifr.ifr_name, device, IFNAMSIZ);

if((ioctl(rawsock, SIOCGIFINDEX, &ifr)) == -1)

{

printf("Error getting Interface index !\n");

exit(-1);

}

/* Bind raw socket to this interface */

sll.sll_family = AF_PACKET;

sll.sll_ifindex = ifr.ifr_ifindex;

sll.sll_protocol = htons(protocol);

if((bind(rawsock, (struct sockaddr *)&sll, sizeof(sll)))== -1)

{

perror("Error binding raw socket to interface\n");

exit(-1);

}

return 1;

}

void PrintPacketInHex(unsigned char *packet, int len)

{

unsigned char *p = packet;

printf("\n\n---------Packet---Starts----\n\n");

while(len--)

{

printf("%.2x ", *p);

p++;

}

printf("\n\n--------Packet---Ends-----\n\n");

}

PrintInHex(char *mesg, unsigned char *p, int len)

{

printf(mesg);

while(len--)

{

printf("%.2X ", *p);

p++;

}

}

ParseEthernetHeader(unsigned char *packet, int len)

{

struct ethhdr *ethernet_header;

if(len > sizeof(struct ethhdr))

{

ethernet_header = (struct ethhdr *)packet;

/* First set of 6 bytes are Destination MAC */

PrintInHex("Destination MAC: ",ethernet_header->h_dest,6);

printf("\n");

/* Second set of 6 bytes are Source MAC */

PrintInHex("Source MAC: ",ethernet_header->h_source,6);

printf("\n");

/* Last 2 bytes in Ethernet header is the protocol */

PrintInHex("Protocol: ",(void *)

&ethernet_header->h_proto, 2);

printf("\n");

}

else

{

printf("Packet size too small !\n");

}

}

ParseIpHeader(unsigned char *packet, int len)

{


struct iphdr *ip_header;

/*Check if packet contains IP header using Ethernet header*/


if(ntohs(ethernet_header->h_proto) == ETH_P_IP)

{

/* The IP header is after the Ethernet header */

if(len >= (sizeof(struct ethhdr)+sizeof(struct iphdr)))

{

ip_header=(struct iphdr*)(packet+sizeof(struct ethhdr));

/* print the Source and Destination IP address */

printf("Dest IP address: %s\n",

inet_ntoa(ip_header->daddr));

printf("Source IP address: %s\n",

inet_ntoa(ip_header->saddr));

}

else

{

printf("IP packet does not have full header\n");

}

}

}

ParseTcpHeader(unsigned char *packet , int len)

{



struct tcphdr *tcp_header;

/* Check if enough bytes are there for TCP Header */

if(len >= (sizeof(struct ethhdr) + sizeof(struct iphdr) +

sizeof(struct tcphdr)))

{

/* Do the checks: Is it an IP pkt and is it TCP ? */



{

ip_header = (struct iphdr *)(packet +

sizeof(struct ethhdr));

if(ip_header->protocol == IPPROTO_TCP)

{

tcp_header = (struct tcphdr*)(packet +

sizeof(struct ethhdr) + ip_header->ihl*4 );

/* Print the Dest and Src ports */

printf("Source Port:%d\n",ntohs(tcp_header->source));

printf("Dest Port: %d\n", ntohs(tcp_header->dest));

}

else

{

printf("Not a TCP packet\n");

}

}

else

{

printf("Not an IP packet\n");

}

}

else

{

printf("TCP Header not present \n");

}

}

int ParseData(unsigned char *packet, int len)

{



struct tcphdr *tcp_header;

unsigned char *data;

int data_len;

/* Check if any data is there */

if(len > (sizeof(struct ethhdr) + sizeof(struct iphdr) + sizeof(struct tcphdr)))

{

ip_header = (struct iphdr*)(packet +


data = (packet + sizeof(struct ethhdr) +

ip_header->ihl*4 +sizeof(struct tcphdr));

data_len = ntohs(ip_header->tot_len) - ip_header->ihl*4- sizeof(struct tcphdr);

if(data_len)

{

printf("Data Len : %d\n", data_len);

PrintInHex("Data : ", data, data_len);

printf("\n\n");

return 1;

}

else

{

printf("No Data in packet\n");

return 0;

}

}

else

{

printf("No Data in packet\n");

return 0;

}

}

int IsIpAndTcpPacket(unsigned char *packet, int len)

{





{

ip_header = (struct iphdr *)(packet +


if(ip_header->protocol == IPPROTO_TCP)

return 1;

else

return -1;

}

else

return -1;

}

main(int argc, char **argv)

{

int raw;

unsigned char packet_buffer[2048];

int len;

int packets_to_sniff;

struct sockaddr_ll packet_info;

int packet_info_size = sizeof(packet_info);

/* create the raw socket */

raw = CreateRawSocket(ETH_P_IP);

/* Bind socket to interface */

BindRawSocketToInterface(argv[1], raw, ETH_P_IP);

/* Get number of packets to sniff from user */

packets_to_sniff = atoi(argv[2]);

/* Start Sniffing and print Hex of every packet */

while(packets_to_sniff--)

{

if((len = recvfrom(raw, packet_buffer, 2048, 0,

(struct sockaddr*)&packet_info, &packet_info_size))== -1)

{

perror("Recv from returned -1: ");

exit(-1);

}

else

{

/* Packet has been received successfully !! */

PrintPacketInHex(packet_buffer, len);

/* Parse Ethernet Header */

ParseEthernetHeader(packet_buffer, len);

/* Parse IP Header */

ParseIpHeader(packet_buffer, len);

/* Parse TCP Header */

ParseTcpHeader(packet_buffer, len);

if(IsIpAndTcpPacket(packet_buffer, len))

{

if(!ParseData(packet_buffer, len))

packets_to_sniff++;

}

}

}

return 0;

}

OUTPUT

$su

Password:

# gcc sniffdata.c -o sniffdata

# ifconfig eth0 promisc

# ./sniffdata eth0 1

---------Packet---Starts----

01 00 5e 7f ff fa 18 f4 6a 16 a2 a2 08 00 45 00 01 ff 2a ec 00

00 01 11 ec 11 ac 10 04 e6 ef ff ff fa 07 6c 07 6c 01 eb 65 d1

4e 4f 54 49 46 59 20 2a 20 48 54 54 50 2f 31 2e 31 0d 0a 48 6f

73 74 3a 32 33 39 2e 32 35 35 2e 32 35 35 2e 32 35 30 3a 31 39

30 30 0d 0a 4e 54 3a 75 72 6e 3a 64 6d 63 2d 73 61 6d 73 75 6e

67 2d 63 6f 6d 3a 64 65 76 69 63 65 3a 53 79 6e 63 53 65 72 76

65 72 3a 31 0d 0a 4e 54 53 3a 73 73 64 70 3a 61 6c 69 76 65 0d

0a 4c 6f 63 61 74 69 6f 6e 3a 68 74 74 70 3a 2f 2f 31 37 32 2e

31 36 2e 34 2e 32 33 30 3a 32 38 36 39 2f 75 70 6e 70 68 6f 73

74 2f 75 64 68 69 73 61 70 69 2e 64 6c 6c 3f 63 6f 6e 74 65 6e

--------Packet---Ends-----

Destination MAC: 01 00 5E 7F FF FA

Source MAC: 18 F4 6A 16 A2 A2

Protocol: 08 00

Dest IP address: 239.255.255.250

Source IP address: 172.16.4.230

Not a TCP packet

Data Len : 471

Data : 50 2F 31 2E 31 0D 0A 48 6F 73 74 3A 32 33 39 2E 32 35

35 2E 32 35 35 2E 32 35 30 3A 31 39 30 30 0D 0A 4E 54 3A 75 72

6E 3A 64 6D 63 2D 73 61 6D 73 75 6E 67 2D 63 6F 6D 3A 64 65 76

69 63 65 3A 53 79 6E 63 53 65 72 76 65 72 3A 31 0D 0A 4E 54 53

3A 73 73 64 70 3A 61 6C 69 76 65 0D 0A 4C 6F 63 61 74 69 6F 6E

3A 68 74 74 70 3A 2F 2F 31 37 32 2E 31 36 2E 34 2E 32 33 30 3A

32 38 36 39 2F 75 70 6E 70 68 6F 73 74 2F 75 64 68 69 73 61 70

69 2E 64 6C 6C 3F 63 6F 6E 74 65 6E

RESULT

Thus packets that pass through the host were sniffed. The Ethernet, IP and TCP headers

along with data contents were parsed.


EX.NO: 4.a REMOTE PROCEDURE CALL

DATE: ARITHMETIC CALCULATOR USING RPC-RMI

AIM

To implement simple calculator and invoke arithmetic operations from a remote client.

ALGORITHM

Interface

1. Declare server's remote interface for simple arithmetic operations such as addition,

subtraction, multiplication, division, etc.

Implementation

1. Define arithmetic operation modules for all interfaces.

2. Create a calc object.

3. Register the calc object with RMI registry using rebind method.

Client

1. Obtain operands from the user.

2. Check for rmi calc service availability using lookup method.

3. Call arithmetic operations on the remote server.

4. Display results.

Procedure

1. Compile the three java files (Interface, Implementation and Client).

2. Generate stub by compiling the implementation file using RMI compiler (rmic).

3. Distribute the class files of Client, Interface and Stub to the clients.

4. Start the RMI registry on the server.

5. Start the server (implementation file).

6. Run the client program.

PROGRAM

// RMI Calc interface -- CalcInf.java

import java.rmi.*;

public interface CalcInf extends Remote

{

public long add(int a, int b) throws RemoteException;

public int sub(int a, int b) throws RemoteException;

public long mul(int a, int b) throws RemoteException;

public int div(int a, int b) throws RemoteException;

public int rem(int a, int b) throws RemoteException;

}

// RMI Calc Implementation -- CalcImpl.java

import java.rmi.*;

import java.rmi.server.*;

public class CalcImpl extends UnicastRemoteObject implements CalcInf

{

public CalcImpl() throws RemoteException { }

public long add(int a, int b) throws RemoteException

{

return a + b;

}

public int sub(int a, int b) throws RemoteException

{

int c = a > b ? a - b : b - a;

return c;

}

public long mul(int a, int b) throws RemoteException

{

return a * b;

}

public int div(int a, int b) throws RemoteException

{

return a / b;

}

public int rem(int a, int b) throws RemoteException

{

return a % b;

}


{

try

{

calcinf C = new calcimpl();

Naming.rebind("Calc1234", C);

}

catch (Exception e)

{

System.out.println(e);

}

}

}

// RMI Calc Client -- CalcClient.java

import java.rmi.*;

import java.net.*;

public class CalcClient

{


{

try {

CalcInf C = (CalcInf)

Naming.lookup("rmi://localhost/Calc1234");

int a, b;

if (args.length != 2)

{

System.out.println("Usage: java CalcClient ");

System.exit(-1);

}

a = Integer.parseInt(args[0]);

b = Integer.parseInt(args[1]);

System.out.println( "\nBasic Remote Calc\n" );

System.out.println("Summation : " + C.add(a, b));

System.out.println("Difference : " + C.sub(a, b));

System.out.println("Product : " + C.mul(a, b));

System.out.println("Quotient : " + C.div(a, b));

System.out.println("Remainder : " + C.rem(a, b));

}

catch (Exception E) {


}

}

}

OUTPUT

Server

$ javac CalcInf.java

$ javac CalcImpl.java

$ javac CalcClient.java

$ rmic CalcImpl

$ mkdir clnt

$ cp CalcInf.class CalcClient.class CalcImpl_Stub.class ./clnt

$ rmiregistry&

$ java CalcImpl

Client

$ cd clnt

$ java CalcClient 6 8

Basic Remote Calc

Summation : 14

Difference : 2

Product : 48

Quotient : 0

Remainder : 6

RESULT

Thus remote procedure calls for basic operations of a calculator is executed using Java

RMI.

EX.NO: 4.b SORTING

DATE:

AIM

To implement bubble sort and sort data using a remote client.

ALGORITHM

Interface

1. Declare server's remote interface for bubble sort.

Implementation

1. Define bubble sort procedure.

2. Create a sort object.

3. Register the sort object with RMI registry using rebind method.

Client

1. Obtain unsorted data from the user.

2. Check for rmi sort service availability using lookup method.

3. Call sort method on the remote server.

4. Display the sorted array.

Procedure







PROGRAM

// RMI Sort interface -- sortinf.java

import java.rmi.*;

public interface sortinf extends Remote

{

public int[] sort(int a[], int n) throws RemoteException;

}

//RMI Sort Implementation -- sortimpl.java

import java.rmi.*;


public class sortimpl extends UnicastRemoteObject implements sortinf

{

public sortimpl() throws RemoteException { }

public int[] sort(int a[], int n) throws RemoteException

{

int i,j,t;

for(i=0; i

// RMI Sort Client -- sortclient.java

import java.rmi.*;

import java.net.*;

public class sortclient

{


{

try

{

sortinf S = (sortinf)

Naming.lookup("rmi://localhost/Sort1234");

int i;

int n = args.length;

int a[] = new int[n];

int b[] = new int[n];

for(i=0; i

OUTPUT

Server

$ javac sortinf.java

$ javac sortimpl.java

$ javac sortclient.java

$ rmic sortimpl

$ mkdir clnt

$ cp sortinf.class sortclient.class sortimpl_Stub.class ./clnt

$ rmiregistry&

$ java sortimpl

Client

$ cd clnt

$ java sortclient 8 4 0 3 -2 5 1 6

Sorted array : -2 0 1 3 4 5 6 8

RESULT

Thus remote procedure calls is made to sort a random data set using Java RMI.

EX.NO: 4.c STRING REVERSE

DATE:

AIM

To implement string manipulations on a remote host and perform string operations.

ALGORITHM

Interface

1. Declare server's remote interface for string reverse.

Implementation

1. Define string reverse using string buffer class methods.

2. Create a stringfn object.

3. Register the stringfn object with RMI registry using rebind method.

Client

1. Obtain text from the user.

2. Check for rmi stringfn service availability using lookup method.

3. Call string operations on the remote server.

4. Display results.

Procedure







PROGRAM

// RMI string interface -- strinf.java

import java.rmi.*;

public interface strinf extends Remote

{

public String strfn(String s) throws RemoteException;

}

// RMI string implementation -- strimpl.java

import java.rmi.*;


public class strimpl extends UnicastRemoteObject implements

strinf {

public strimpl() throws RemoteException { }

public String strfn(String s) throws RemoteException

{

StringBuffer s1 = new StringBuffer(s);

s1.reverse();

return (s1.toString()); //String Revers

/* return (s.toUpperCase()); */ // Lower-to-Upper Case

/* return s; */ // Remote Echo server

}

public static void main(String arg[])

{

try

{

strinf si = new strimpl();

Naming.rebind("Str1234", si);

}

catch(Exception e)

{

System.out.println(e);

}

}

}

// RMI String Client -- strclient.java

import java.rmi.*;

import java.net.*;

public class strclient

{


{

try

{

strinf S = (strinf)

Naming.lookup("rmi://localhost/Str1234");

if (args.length != 1)

{

System.out.println( "Usage: java strclient

");

System.exit(-1);

}

System.out.println( "Output String : " +

S.strfn(args[0]));

}

catch (Exception E)

{


}

}

}

OUTPUT

Server

$ javac strinf.java

$ javac strimpl.java

$ javac strclient.java

$ rmic strimpl

$ mkdir clnt

$ cp strinf.class strclient.class strimpl_Stub.class ./clnt

$ rmiregistry&

$ java strimpl

Client

$ cd clnt

$ java strclient SMKFIT

Output String : TIFKMS

RESULT

Thus remote procedure calls for string manipulation is executed using Java RMI.


PROTOCOL SIMULATION

EX.NO: 5.a GO BACK N ARQ

DATE:

AIM

To simulate a sliding window protocol that uses Go Back N ARQ.

ALGORITHM

Sender


2. Assume the sending window size as 7 (m = 3).

3. If receiver is ready, initialize sender's frame sequence to 0.

4. Get data from user.

5. Send it to the receiver along with sequence number.

6. Increment sequence number by 1.

7. Repeat steps 46 until all frames have been sent.

8. Wait for acknowledgements.

9. If all acknowledgements have arrived then go to step 12.

10. Set sequence number to earliest outstanding frame for which there is no ACK.

11. Go to step 4.

12. Stop

Receiver

1. Indicate to sender, the readiness to accept frames.

2. Initialize receiver's expected frame sequence to 0.

3. Accept the incoming frame.

4. If frame's sequence receiver's sequence then go to step 7.

5. Send an acknowledgement.

6. Repeat steps 36 until all frames are received in sequence and go to step 9

7. Discard frame, thereby force the sender to retransmit.

8. Go to step 3.

9. Stop

PROGRAM

// Go Back N Sender--GBNSend.java

import java.io.*;

import java.net.*;

public class GBNSend

{

String output[] = new String[7];

void sendMsg(BufferedReader buff, BufferedReader in,PrintWriter out, int x) throws Exception

{

try

{

for(int i=x; i

else

{

System.out.println("Frame" + j + " lost/corrupt.Go Back & resend");

x = j;

g.sendMsg(buff,in,out,j);

--j;

}

}

soc.close();

ssoc.close();

}

}

//Go Back N Receiver--GBNReceive.java

import java.io.*;

import java.net.*;

public class GBNReceive

{

String input[] = new String[7];

void ReceiveMsg(BufferedReader buff, PrintWriter out,

int x) throws Exception

{

try

{

for(int i=x; i

if(g.input[j].startsWith(s))

{

String rmsg = g.input[j];

rmsg = rmsg.substring(1,rmsg.length());

System.out.println("Frame" + j + "data is " + rmsg);

out.println(j + "ack");

out.flush();

}

else

{

out.println("no ack");

out.flush();

x = j;

g.ReceiveMsg(buff,out,j);

--j;

}

}

soc.close();

}

}

OUTPUT

Sender

$ javac GBNSend.java

$ java GBNSend

Window size 7

Enter message in format--SeqNoData

Content for frame0 : 0hi

Content for frame1 : 1hello

Content for frame2 : 2i am here

Content for frame3 : 3where r u?

Content for frame4 : here only

Content for frame5 : 5can u see me

Content for frame6 : 6which direction

Ack for frame0

Ack for frame1

Ack for frame2

Ack for frame3

Frame4 lost/corrupt. Go Back & resend

Content for frame4 : 4here only


Content for frame6 : ok

Ack for frame4

Ack for frame5

Frame6 lost/corrupt. Go Back & resend

Content for frame6 : 6South

Ack for frame6

Receiver

$ javac GBNReceive.java

$ java GBNReceive

Frame0 data is hi

Frame1 data is hello

Frame2 data is i am here

Frame3 data is where r u?

Frame4 data is here only

Frame5 data is which direction

Frame6 data is South

RESULT

Thus using Go Back N procedure, the sender retransmits all frames from the earliest

outstanding frame.

EX.NO: 5.b SELECTIVE REPEAT ARQ

DATE:

AIM

To simulate a sliding window protocol that uses Selective Repeat ARQ.

ALGORITHM

Sender


2. Assume sending window size as 7.

3. If receiver is ready, initialize sender's frame sequence to 0.

4. Get data from user.

5. Send it to receiver along with sequence number.

6. Increment sequence number by 1.

7. Repeat steps 46 until all frames have been sent.

8. Wait for acknowledgements.

9. If all acknowledgements have arrived then go to step 12

10. Resend the earliest outstanding frame for which there is no ACK.

11. Go to step 8.

12. Stop

Receiver

1. Indicate to the sender, the readiness to accept frames.

2. Initialize receiver's expected frame sequence to 0.

3. Accept the incoming frame.

4. If frame is corrupt then step 8.

5. If frames are in order then step 6 else step 3.

6. Send acknowledgements.

7. If ACK for all frames are sent then go to step 10

8. Discard the frame, thereby force the sender to retransmit

9. Go to step 3

10. Stop

PROGRAM

// Selective Repeat Sender--SRSend.java

import java.io.*;

import java.net.*;

public class SRSend

{

String output[] = new String[7];

void sendMsg(BufferedReader buff, BufferedReader in,PrintWriter out, int x, int flag) throws

Exception

{

try

{

if(flag == 1)

{

for(int i=0; i

int x = 0;

g.sendMsg(buff,in,out,0,1);

for(int j=x; j

Socket soc = new Socket("localhost", 6000);

BufferedReader buff = new BufferedReader(new InputStreamReader(soc.getInputStream()));

PrintWriter out = new PrintWriter(new

OutputStreamWriter(soc.getOutputStream()));

int x=0;

g.ReceiveMsg(buff,out,0,1);

for(int j=x; j

OUTPUT

Sender

$ javac SRSend.java

$ java SRSend

Window size 7

Window size 7

Enter message in format--SeqNoData

Content for frame0 : 0hi

Content for frame1 : 1hello

Content for frame2 : 2i am here

Content for frame3 : 3where r u?

Content for frame4 : here only

Content for frame5 : 5can u see me


Ack for frame0

Ack for frame1

Ack for frame2

Ack for frame3

Frame4 lost/corrupt. Resend it

Content for frame4 : 4here only

Ack for frame4

Ack for frame5

Ack for frame6

Receiver

$ javac SRReceive.java

$ java SRReceive

Frame0 data is hi

Frame1 data is hello

Frame2 data is i am here

Frame3 data is where r u?

Frame4 data is here only

Frame5 data is can u see me

Frame6 data is which direction

RESULT

Thus using Selective Repeat procedure, the sender retransmits only frames that are

unacknowledged.

EX.NO: 5.c ARP SERVER/CLIENT

DATE:

AIM

To know the physical address of a host when its logical address is known using ARP

protocol.

ALGORITHM

Target/Server

1. Create a server socket.

2. Accept client connection.

3. Read IP address from the client request

4. Check its configuration file and compare with its logical address.

5. If there is a match, send the host physical address.

6. Stop

Client

1. Create a socket.

2. Send IP address to the target machine

3. Receive target's response

4. If it is a MAC address then display it and go to step 6

5. Display "Host not found"

6. Stop

PROGRAM

//ARP Server -- arpserver.java

import java.io.*;

import java.net.*;

class arpserver

{


{

try

{

ServerSocket soc = new ServerSocket(2500);

System.out.println("Server started");


client = soc.accept();

String str;

PrintStream ps = new PrintStream(client.getOutputStream());

BufferedReader br = new BufferedReader(new InputStreamReader(client.getInputStream()));

Runtime r = Runtime.getRuntime();

Process p = r.exec("ifconfig eth0");

BufferedReader pin=new BufferedReader(new InputStreamReader(p.getInputStream()));

String haddr = "";

String ipaddr = br.readLine();

int flag = 0;

while((str = pin.readLine())!=null)

{

System.out.println(str);

if((str.indexOf("HWaddr")) != -1)

{

int tlen = str.length();

int hlen = tlen - 19;

haddr = str.substring(hlen,tlen);

}

else if ((str.indexOf(ipaddr)) != -1)

{

flag = 1;

}

}

if (flag == 1)

ps.println(haddr);

ps.close();

br.close();

pin.close();

client.close();

soc.close();

}

catch(IOException io)

{

System.err.println("Exception : " + io.toString());

}

}

}

//ARP Client -- arpclient.java

import java.io.*;

import java.net.*;

class arpclient

{


{

try

{

Socket client = new Socket("localhost", 2500);



String ipaddr,haddr = null;

BufferedReader sin = new BufferedReader(new InputStreamReader(client.getInputStream()));

System.out.print("Enter the IP address : ");

ipaddr = br.readLine();

ps.println(ipaddr);

haddr = sin.readLine();

if (haddr == null)

System.out.println("Host does not exist");

else

System.out.println("Physical Address " + haddr);

ps.close();

br.close();

client.close();

}


{

System.err.println(io.toString());

}

}

}

OUTPUT

Server

$ javac arpserver.java

$ java arpserver

Server started

eth0 Link encap:Ethernet HWaddr B8:AC:6F:1B:AB:06

inet addr:172.16.12.251 Bcast:172.255.255.255 Mask:255.0.0.0

inet6 addr: fe80::baac:6fff:fe1b:ab06/64 Scope:Link

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

RX packets:450 errors:0 dropped:0 overruns:0 frame:0

TX packets:127 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:1000

RX bytes:48118 (46.9 KiB) TX bytes:21025 (20.5 KiB)

Interrupt:16

Client

$ javac arpclient.java

$ java arpclient

Enter the IP address : 172.16.12.251

Physical Address B8:AC:6F:1B:AB:06

RESULT

Thus using Address Rresolution Protoocl, a hosts MAC address is obtained.

EX.NO: 5.d RARP CLIENT/SERVER

DATE:

AIM

To know the logical address of a host when its physical address is known using RARP

protocol.

ALGORITHM

Target/Server

1. Create a server socket.

2. Accept client connection.

3. Read MAC address from the client request

4. Check its configuration file and compare with its physical address.

5. If there is a match, send the host logical address.

6. Stop

Client

1. Create a socket.

2. Send physical address to the target machine

3. Receive target's response

4. If it is a IP address then display it and go to step 6

5. Display "Host not found"

6. Stop

PROGRAM

//RARP Server -- rarpserver.java

import java.io.*;

import java.net.*;

class rarpserver

{


{

try

{

ServerSocket soc = new ServerSocket(2500);

System.out.println("Server started");


client = soc.accept();

String str;


BufferedReader br = new BufferedReader(new InputStreamReader(client.getInputStream()));

Runtime r = Runtime.getRuntime();

Process p = r.exec("ifconfig eth0");

BufferedReader pin = new BufferedReader(new InputStreamReader(p.getInputStream()));

String ipaddr = "";

String haddr = br.readLine();

int flag = 0;

while((str = pin.readLine())!=null)

{

System.out.println(str);

if ((str.indexOf(haddr)) != -1)

{

flag = 1;

}

else if((str.indexOf("inet addr")) != -1)

{

int pos = str.indexOf("inet addr:") + 10;

int offset = pos + 13;

ipaddr = str.substring(pos,offset);

}

}

if (flag == 1)

ps.println(ipaddr);

ps.close();

br.close();

pin.close();

client.close();

soc.close();

}


{

System.err.println("Exception : " + io.toString());

}

}

}

// RARP Client -- rarpclient.java

import java.io.*;

import java.net.*;

class rarpclient

{


{

try

{

Socket client = new Socket("localhost", 2500);


PrintStream ps = new

PrintStream(client.getOutputStream());

String haddr,ipaddr = null;

BufferedReader sin = new BufferedReader(new InputStreamReader(client.getInputStream()));

System.out.print("Enter the physical address : ");

haddr = br.readLine();

ps.println(haddr);

ipaddr = sin.readLine();

if (ipaddr == null)

System.out.println("Host does not exist");

else

System.out.println("Logical Address " + ipaddr);

ps.close();

br.close();

client.close();

}


{

System.err.println(io.toString());

}

}

}

OUTPUT

Server

$ javac rarpserver.java

$ java rarpserver

Server started

eth0 Link encap:Ethernet HWaddr B8:AC:6F:1B:AB:06

inet addr:172.16.12.251 Bcast:172.255.255.255 Mask:255.0.0.0

inet6 addr: fe80::baac:6fff:fe1b:ab06/64 Scope:Link

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

RX packets:450 errors:0 dropped:0 overruns:0 frame:0

TX packets:127 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:1000

RX bytes:48118 (46.9 KiB) TX bytes:21025 (20.5 KiB)

Interrupt:16

Client

$ javac rarpclient.java

$ java rarpclient

Enter the physical address : B8:AC:6F:1B:AB:06

Logical Address 172.16.12.251

RESULT

Thus using Reverse ARP protocol, IP address of a host is obtained.


EX.NO: 6.a EXPERIMENTS USING SIMULATORS

DATE: USER DATAGRAM PROTOCOL USING NS-2

AIM:

To implement User Datagram Protocol (UDP) using NS-2

ALGORITHM:

Step 1: Start network simulator OTCL editor.

Step 2: Create new simulator using set ns [new Simulator] syntax

Step 3: Create procedure to trace all path

proc finish {} {

global ns nf tf

$ns flush-trace

close $nf

close $tf

exec nam udp.nam &

exit 0 }

Step 4: Connect with TCP and SINK command.

$ns connect $tcp $sink

Step 5: Run and Execute the program.

$ns run

PROGRAM:

set ns [new Simulator]

set nf [open udp.nam w]

$ns namtrace-all $nf

set tf [open out.tr w]

$ns trace-all $tf

proc finish {} {

global ns nf tf

$ns flush-trace

close $nf

close $tf

exec nam udp.nam &

exit 0

}

set n0 [$ns node]

set n1 [$ns node]

set n2 [$ns node]

set n3 [$ns node]

set n4 [$ns node]

set n5 [$ns node]

$ns duplex-link $n0 $n4 1Mb 50ms DropTail


$ns duplex-link $n2 $n5 0.1Mb 1ms DropTail



$ns duplex-link-op $n2 $n5 queuePos 1

set tcp [new Agent/UDP]

$ns attach-agent $n0 $tcp

set sink [new Agent/Null]

$ns attach-agent $n2 $sink


set ftp [new Application/Traffic/CBR]

$ftp attach-agent $tcp

$ns at 0.0 "$ftp start"

$ns at 2.5 "$ftp stop"

$ns at 3 "finish"

$ns run

OUTPUT:

RESULT:

Thus the program for implementing UDP was executed using NS-2 and output verified

using Network Animator.

EX.NO: 6.b TRANSMISSION CONTROL PROTOCOL USING NS-2

DATE:

AIM:

To implement Transmission Control Protocol (TCP) using NS-2

ALGORITHM:

Step 1: Start network simulator OTCL editor.

Step 2: Create new simulator using set ns [new Simulator] syntax

Step 3: Create procedure to trace all path

proc finish {} {

global ns nf tf

$ns flush-trace

close $nf

close $tf

exec nam tcp.nam &

exit 0}

Step 4: Connect with TCP and SINK command.


Step 5: Run and Execute the program.

$ns run

PROGRAM:


set nf [open tcp.nam w]


set tf [open out.tr w]

$ns trace-all $tf

proc finish {} {

global ns nf tf

$ns flush-trace

close $nf

close $tf

exec nam tcp.nam &

exit 0

}

set n0 [$ns node]

set n1 [$ns node]

set n2 [$ns node]

set n3 [$ns node]

set n4 [$ns node]

set n5 [$ns node]






$ns duplex-link-op $n4 $n5 queuePos 0.5

set tcp [new Agent/TCP]


set sink [new Agent/TCPSink]



set ftp [new Application/FTP]




$ns at 3 "finish"

$ns run

OUTPUT:

RESULT:

Thus, the program for implementing TCP was executed using NS-2 and output verified

using Network Animator.


EX.NO: 7 ETHERNET CSMA/CD PROTOCOL

DATE:

AIM

To study transmission of packets over Ethernet LAN and its CSMA/CD protocol

ALGORITHM

1. Create a simulator object

2. Set different color for TCP and UDP traffic.

3. Trace packets on all links onto NAM trace and text trace file

4. Define finish procedure to close files, flush tracing and run NAM

5. Create six nodes

6. Specify the link characteristics between nodes

7. Create a LAN with nodes n3, n4, n5 part of it

8. Describe layout topology of nodes

9. Add UDP agent for node n1

10. Create CBR traffic on top of UDP and set traffic parameters.

11. Add a null agent to node and connect it to udp source

12. Add TCP agent for node n0

13. Create FTP traffic for TCP and set its parameters

14. Add a sink to TCP and connect it to source

15. Schedule events as follows:

a. Start CBR & FTP traffic flow at 0.3 and 0.8 respectively

b. Stop CBR & FTP traffic flow at 7.5 and 7.0 respectively

c. Call finish procedure at 8.0

16. Start the scheduler

17. Observe the transmission of packets over LAN

18. View the simulated events and trace file analyze it

19. Stop

PROGRAM

#Lan simulation mac.tcl


#define color for data flows

$ns color 1 Purple

$ns color 2 MAgenta

#open tracefile

set tracefile1 [open out.tr w]

$ns trace-all $tracefile1

#open nam file

set namfile [open out.nam w]

$ns namtrace-all $namfile

#define the finish procedure

proc finish {} {

global ns tracefile1 namfile

$ns flush-trace

close $tracefile1

close $namfile

exec nam out.nam &

exit 0

}

#create six nodes

set n0 [$ns node]

set n1 [$ns node]

set n2 [$ns node]

set n3 [$ns node]

set n4 [$ns node]

set n5 [$ns node]

# Specify color and shape for nodes

$n1 color MAgenta

$n1 shape box

$n5 color MAgenta

$n5 shape box

$n0 color Purple

$n4 color Purple

#create links between the nodes



$ns simplex-link $n2 $n3 0.3Mb 100ms DropTail

$ns simplex-link $n3 $n2 0.3Mb 100ms DropTail

# Create a LAN

set lan [$ns newLan "$n3 $n4 $n5" 0.5Mb 40ms LL Queue/DropTail

MAC/Csma/Cd Channel]

#Give node position

$ns duplex-link-op $n0 $n2 orient right-down

$ns duplex-link-op $n1 $n2 orient right-up

$ns simplex-link-op $n2 $n3 orient right

$ns simplex-link-op $n3 $n2 orient left

#setup TCP connection

set tcp [new Agent/TCP/Newreno]


set sink [new Agent/TCPSink/DelAck]



$tcp set fid_ 1

$tcp set packet_size_ 552

#set ftp over tcp connection

set ftp [new Application/FTP]


#setup a UDP connection

set udp [new Agent/UDP]

$ns attach-agent $n1 $udp

set null [new Agent/Null]

$ns attach-agent $n5 $null

$ns connect $udp $null

$udp set fid_ 2

#setup a CBR over UDP connection

set cbr [new Application/Traffic/CBR]

$cbr attach-agent $udp

$cbr set type_ CBR

$cbr set packet_size_ 1000

$cbr set rate_ 0.05Mb

$cbr set random_ false

#scheduling the events

$ns at 0.0 "$n0 label TCP_Traffic"

$ns at 0.0 "$n1 label UDP_Traffic"

$ns at 0.3 "$cbr start"



$ns at 7.5 "$cbr stop"

$ns at 8.0 "finish"

$ns run

OUTPUT

$ ns mac.tcl

RESULT

Thus broadcasting of packets over ethernet LAN and collision of packets was observered.


EX.NO: 8 DISTANCE VECTOR ROUTING PROTOCOL

DATE:

AIM

To simulate a link failure and to observe distance vector routing protocol in action.

ALGORITHM


2. Set routing protocol to Distance Vector routing

3. Trace packets on all links onto NAM trace and text trace file

4. Define finish procedure to close files, flush tracing and run NAM

5. Create eight nodes

6. Specify the link characteristics between nodes

7. Describe their layout topology as a octagon

8. Add UDP agent for node n1

9. Create CBR traffic on top of UDP and set traffic parameters.

10. Add a sink agent to node n4

11. Connect source and the sink

12. Schedule events as follows:

. Start traffic flow at 0.5

b. Down the link n3-n4 at 1.0

c. Up the link n3-n4 at 2.0

d. Stop traffic at 3.0

. Call finish procedure at 5.0

13. Start the scheduler

14. Observe the traffic route when link is up and down

15. View the simulated events and trace file analyze it

16. Stop

PROGRAM

#Distance vector routing protocol distvect.tcl

#Create a simulator object


#Use distance vector routing

$ns rtproto DV

#Open the nam trace file

set nf [open out.nam w]


# Open tracefile

set nt [open trace.tr w]

$ns trace-all $nt

#Define 'finish' procedure

proc finish {} {

global ns nf

$ns flush-trace

#Close the trace file

close $nf

#Execute nam on the trace file

exec nam -a out.nam &

exit 0

}

# Create 8 nodes

set n1 [$ns node]

set n2 [$ns node]

set n3 [$ns node]

set n4 [$ns node]

set n5 [$ns node]

set n6 [$ns node]

set n7 [$ns node]

set n8 [$ns node]

# Specify link characterestics









# specify layout as a octagon

$ns duplex-link-op $n1 $n2 orient left-up

$ns duplex-link-op $n2 $n3 orient up


$ns duplex-link-op $n4 $n5 orient right


$ns duplex-link-op $n6 $n7 orient down

$ns duplex-link-op $n7 $n8 orient left-down

$ns duplex-link-op $n8 $n1 orient left

#Create a UDP agent and attach it to node n1

set udp0 [new Agent/UDP]

$ns attach-agent $n1 $udp0

#Create a CBR traffic source and attach it to udp0

set cbr0 [new Application/Traffic/CBR]

$cbr0 set packetSize_ 500

$cbr0 set interval_ 0.005

$cbr0 attach-agent $udp0

#Create a Null agent (a traffic sink) and attach it to node n4

set null0 [new Agent/Null]

$ns attach-agent $n4 $null0

#Connect the traffic source with the traffic sink

$ns connect $udp0 $null0

#Schedule events for the CBR agent and the network dynamics

$ns at 0.0 "$n1 label Source"

$ns at 0.0 "$n4 label Destination"

$ns at 0.5 "$cbr0 start"

$ns rtmodel-at 1.0 down $n3 $n4

$ns rtmodel-at 2.0 up $n3 $n4

$ns at 4.5 "$cbr0 stop"

#Call the finish procedure after 5 seconds of simulation time

$ns at 5.0 "finish"

#Run the simulation

$ns run

OUTPUT

$ ns distvect.tcl

RESULT

Thus, performance of distance vector protocol and routing path was studied using NS2.


EX.NO:9 STUDY OF UDP PERFORMANCE

DATE:

AIM

To study the performance of UDP by simulating a simple network

ALGORITHM


2. Define different color for data flows

3. Trace all events in a nam file.

4. Create four nodes n0, n1, n2 and n3

5. Describe their layout topology

6. Specify the link capacity between nodes

7. Monitor queue on the link n2 to n3 vertically 90

8. Create a UDP agents udp0, udp1 and attach it to nodes n0 and n1 respectively

9. Create a CBR traffic cbr0, cbr1 and attach it to udp0 and udp1 respectively

10. Create a traffic sink and attach it to node n3

11. Connect sources to the sink

12. Label the nodes

13. Schedule cbr0 to start at 0.5 and stop at 4.5 seconds

14. Schedule cbr1 to start at 1.0 and stop at 4.0 seconds

15. Call finish procedure at 5.0 seconds

16. Run the simulation

17. Execute NAM on the trace file

18. Observe simulated events on the NAM and packet flow on link n2 to n3

19. Stop

PROGRAM

#Study of UDP performance - UDP.tcl



#Define different colors for data flows

$ns color 1 Blue

$ns color 2 Red


set nf [open out.nam w]


#Create four nodes

set n0 [$ns node]

set n1 [$ns node]

set n2 [$ns node]

set n3 [$ns node]

#Create links between the nodes



$ns duplex-link $n3 $n2 1Mb 10ms SFQ

#Specify layout of nodes



$ns duplex-link-op $n2 $n3 orient right

#Monitor the queue for the link 23 vertically

$ns duplex-link-op $n2 $n3 queuePos 0.5



$udp0 set class_ 1


# Create a CBR traffic source and attach it to udp0







$udp1 set class_ 2


# Create a CBR traffic source and attach it to udp1





#Create a Null agent (a traffic sink) and attach it to node n3

set null0 [new Agent/Null]

$ns attach-agent $n3 $null0

#Connect traffic sources with the traffic sink



#Define finish procedure

proc finish {} {

global ns nf

$ns flush-trace

#Close the trace file

close $nf

#Execute nam on the trace file

exec nam -a out.nam &

exit 0

}

#Define label for nodes

$ns at 0.0 "$n0 label Sender1"

$ns at 0.0 "$n1 label Sender2"

$ns at 0.0 "$n2 label Router"

$ns at 0.0 "$n3 label Receiver"

#Schedule events for the CBR agents





#Call finish procedure after 5 seconds of simulation time

$ns at 5.0 "finish"

#Run the simulation

$ns run

OUTPUT

$ ns UDP.tcl

RESULT

Thus the performance of UDP and basic network terminologies were studied using NS2.


EX.NO: 10 STUDY OF TCP PERFORMANCE

DATE:

AIM

To study the performance of a TCP network with droptail queue mechanism on the

gateway

ALGORITHM


2. Define different flows for data flows

3. Trace all events in a nam file and text file

4. Create source nodes (s1, s2, s3), gateway (G) and receiver (r)

5. Describe their layout topology

6. Specify the link between nodes

7. Define the queue size between nodes G and r as 5

8. Monitor queue on all links vertically 90

9. Create TCP agents tcp1, tcp2, tcp3 and attach it to nodes s1, s2 and s3 respectively

10. Create three TCP sinks and attach it to node r

11. Connect traffic sources to the sink

12. Create FTP agents ftp1, ftp2, ftp3 and attach it to tcp1, tcp2 and tcp3 respectively

13. Label the nodes at start time

14. Schedule ftp1, ftp2, ftp3 to start at 0.1 and stop at 5.0 seconds

15. Call finish procedure at 5.25 seconds

16. Run the simulation

17. Execute NAM on the trace file

18. Observe the simulated events on the NAM editor and packet flow on link G to r

19. View the trace file and analyse the events

20. Stop

PROGRAM

#Study of TCP performance - TCP.tcl



#Open trace files

set f [open droptail-queue-out.tr w]

$ns trace-all $f


set nf [open droptail-queue-out.nam w]


#s1, s2 and s3 act as sources.

set s1 [$ns node]

set s2 [$ns node]

set s3 [$ns node]

#G acts as a gateway

set G [$ns node]

#r acts as a receiver

set r [$ns node]

#Define different colors for data flows

$ns color 1 red

$ns color 2 SeaGreen

$ns color 3 blue

#Create links between the nodes

$ns duplex-link $s1 $G 6Mb 10ms DropTail



$ns duplex-link $G $r 3Mb 10ms DropTail

#Define the layout of the nodes

$ns duplex-link-op $s1 $G orient right-up

$ns duplex-link-op $s2 $G orient right

$ns duplex-link-op $s3 $G orient right-down

$ns duplex-link-op $G $r orient right

#Define the queue size for the link between node G and r

$ns queue-limit $G $r 5

#Monitor the queues for links vertically

$ns duplex-link-op $s1 $G queuePos 0.5



$ns duplex-link-op $G $r queuePos 0.5

#Create a TCP agent and attach it to node s1

set tcp1 [new Agent/TCP/Reno]

$ns attach-agent $s1 $tcp1

$tcp1 set window_ 8

$tcp1 set fid_ 1




$tcp2 set window_ 8

$tcp2 set fid_ 2




$tcp3 set window_ 4

$tcp3 set fid_ 3

#Create TCP sink agents and attach them to node r

set sink1 [new Agent/TCPSink]



$ns attach-agent $r $sink1



#Connect the traffic sources with the traffic sinks

$ns connect $tcp1 $sink1



#Create FTP applications and attach them to agents

set ftp1 [new Application/FTP]

$ftp1 attach-agent $tcp1





#Define a 'finish' procedure

proc finish {} {

global ns

$ns flush-trace

puts "running nam..."

exec nam -a droptail-queue-out.nam &

exit 0

}

#Define label for nodes

$ns at 0.0 "$s1 label Sender1"



$ns at 0.0 "$G label Gateway"

$ns at 0.0 "$r label Receiver"

#Schedule ftp events

$ns at 0.1 "$ftp1 start"



$ns at 5.0 "$ftp1 stop"



#Call finish procedure after 5 seconds of simulation time

$ns at 5.25 "finish"

#Run the simulation

$ns run

OUTPUT

$ ns TCP.tcl

RESULT

Thus the behavior of TCP was observed and the basic terminologies of TCP transmission

were understood.


Date post:	04-Sep-2015
Category:	Documents
Upload:	shannon-ross
View:	216 times
Download:	0 times

CN LAB

Documents