DEPARTMENT OF CSC
CRYTOGRAPHY AND NETWORK SECURITY
LAB MANUAL
III B.TECH – I SEM (R18)
A.Y: (2022-23)
___________________________________________________
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MALLA REDDY ENGINEERING COLLEGE & MANAGEMENT SCIENCES
(Approved by AICTE New Delhi & Affiliated to JNTUH, Kistapur (V), Medchal (M),
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Medchal-MalkajgiriDist. -501401
B.TECH III YEAR I SEM
Subject Code:
Course Objectives:
The objectives of information security
To understand the importance and application of each of confidentiality, integrity,
Authentication and availability
To understand various cryptographic algorithms.
To understand the basic categories of threats to computers and networks
Understand Describe public-key cryptosystem.
Understand Describe the enhancements made to IPv4 by IPSec
Understand Intrusions and intrusion detection
Understand Discuss the fundamental ideas of public-key cryptography.
To Generate and distribute a PGP key pair and use the PGP package to send an encrypted
E-mail message.
To Discuss Web security and Firewalls
Course Outcomes:
Student will be able to understand basic cryptographic algorithms, message and web
Authentication and security issues.
Ability to identify information system requirements for both of them such as client and
server.
Ability to understand the current legal issues towards information security.
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List of Experiments:
S.No. Experiment Name Page No.
1. Write a C program that contains a string (char pointer) with a value ‘Hello world’. 4
The program should XOR each character in this string with 0 and displays the
result.
2. Write a C program that contains a string (char pointer) with a value ‘Hello world’.
The program should AND or and XOR each character in this string with 127 and
display the result.
3. Write a Java program to perform encryption and decryption using the following
algorithms.
a. Ceaser cipher b. Substitution cipher c. Hill Cipher
4. Write a C/JAVA program to implement the DES algorithm logic.
5. Write a C/JAVA program to implement the Blowfish algorithm logic.
6. Write a C/JAVA program to implement the Rijndael algorithm logic.
7. Write the RC4 logic in Java Using Java cryptography; encrypt the text “Hello
world” using Blowfish. Create your own key using Java key tool.
8. Write a Java program to implement RSA algorithm.
9. Implement the Diffie-Hellman Key Exchange mechanism using HTML and
JavaScript.
10. Calculate the message digest of a text using the SHA-1 algorithm in JAVA.
11. Calculate the message digest of a text using the MD5 algorithm in JAVA.
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EXPERIMENT NO.1
1. XOR each character in this string with 0.
Aim: Write a C program that contains a string (char pointer) with a value \Hello World’. The
program should XOR each character in this string with 0 and display the result.
PROGRAM:
#include<stdlib.h>
main()
char str[]="Hello World";
char str1[11];
int i,len;
len=strlen(str);
for(i=0;i<len;i++)
str1[i]=str[i]^0;
printf("%c",str1[i]);
printf("\n");
}
Output:
Hello World
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EXPERIMENT NO.2
2. XOR a string with a 127
AIM: Write a C program that contains a string (char pointer) with a value \Hello World’. The
program should AND or and XOR each character in this string with 127 and display the result.
PROGRAM:
#include <stdio.h>
#include <string.h>
#include<stdlib.h>
void main()
char str[]="Hello World";
char str1[11];
char str2[11];
int i,len;
len = strlen(str);
for(i=0;i<len;i++)
str1[i] = str[i]&127;
printf("%c",str1[i]);
printf("\n");
for(i=0;i<len;i++)
{
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Str2[i] = str2[i]^127;
printf("%c",str2[i]);
printf("\n");
Output:
Hello World
Hello World
Hello World
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3. Encryption & Decryption using Cipher Algorithms
AIM: Write a Java program to perform encryption and decryption using the following
algorithms:
a) Ceaser Cipher
b) Substitution Cipher
c) Hill Cipher
PROGRAM:
a) Ceaser Cipher
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Scanner;
public class CeaserCipher {
static Scanner sc=new Scanner(System.in);
static BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); public
static void main(String[] args) throws IOException {
// TODO code application logic here
System.out.print("Enter any String: ");
String str = br.readLine();
System.out.print("\nEnter the Key: ");
int key = sc.nextInt();
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String encrypted = encrypt(str, key);
System.out.println("\nEncrypted String is: " +encrypted);
String decrypted = decrypt(encrypted, key); System.out.println("\nDecrypted String is: "
+decrypted); System.out.println("\n");
}
public static String encrypt(String str, int key) { String encrypted = "";
for(int i = 0; i < str.length(); i++) {
int c = str.charAt(i);
if (Character.isUpperCase(c)) {
c = c + (key % 26);
if (c > 'Z')
c = c - 26;
else if (Character.isLowerCase(c)) {
c = c + (key % 26);
if (c > 'z')
c = c - 26;
encrypted += (char) c;
return encrypted;
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}
public static String decrypt(String str, int key) { String decrypted = "";
for(int i = 0; i < str.length(); i++) {
int c = str.charAt(i);
if (Character.isUpperCase(c)) {
c = c - (key % 26);
if (c < 'A')
c = c + 26;
else if (Character.isLowerCase(c)) {
c = c - (key % 26);
if (c < 'a')
c = c + 26;
decrypted += (char) c;
return decrypted;
Output:
Enter any String: Hello World
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Enter the Key: 5
Encrypted String is: MjqqtBtwqi
Decrypted String is: Hello World
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b) Substitution Cipher
PROGRAM: import java.io.*; import java.util.*;
public class SubstitutionCipher {
static Scanner sc = new Scanner(System.in);
static BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); public
static void main(String[] args) throws IOException {
// TODO code application logic here
String a = "abcdefghijklmnopqrstuvwxyz";
String b = "zyxwvutsrqponmlkjihgfedcba";
System.out.print("Enter any string: ");
String str = br.readLine();
String decrypt = "";
char c;
for(int i=0;i<str.length();i++)
c = str.charAt(i);
int j = a.indexOf(c);
decrypt = decrypt+b.charAt(j);
System.out.println("The encrypted data is: " +decrypt);
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Output:
Enter any string: aceho
The encrypted data is: zxvsl
C) Hill Cipher
PROGRAM:
import java.io.*;
import java.util.*;
import java.io.*;
public class HillCipher {
static float[][] decrypt = new float[3][1];
static float[][] a = new float[3][3];
static float[][] b = new float[3][3];
static float[][] mes = new float[3][1];
static float[][] res = new float[3][1];
static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
static Scanner sc = new Scanner(System.in);
public static void main(String[] args) throws IOException {
// TODO code application logic here
getkeymes();
for(int i=0;i<3;i++)
for(int j=0;j<1;j++)
for(int k=0;k<3;k++)
{ res[i][j]=res[i][j]+a[i][k]*mes[k][j];
} System.out.print("\nEncrypted string is : ");
for(int i=0;i<3;i++)
{ System.out.print((char)(res[i][0]%26+97));
res[i][0]=res[i][0];
inverse();
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for(int i=0;i<3;i++)
for(int j=0;j<1;j++)
for(int k=0;k<3;k++) {
decrypt[i][j] = decrypt[i][j]+b[i][k]*res[k][j];
}
System.out.print("\nDecrypted string is : ");
for(int i=0;i<3;i++)
{ System.out.print((char)(decrypt[i][0]%26+97));
System.out.print("\n");
public static void getkeymes() throws IOException {
System.out.println("Enter 3x3 matrix for key (It should be inversible): ");
for(int i=0;i<3;i++)
for(int j=0;j<3;j++)
a[i][j] = sc.nextFloat();
System.out.print("\nEnter a 3 letter string: ");
String msg = br.readLine();
for(int i=0;i<3;i++)
mes[i][0] = msg.charAt(i)-97;
public static void inverse() {
floatp,q;
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float[][] c = a;
for(int i=0;i<3;i++)
for(int j=0;j<3;j++) {
//a[i][j]=sc.nextFloat();
if(i==j)
b[i][j]=1;
else b[i][j]=0;
for(int k=0;k<3;k++) {
for(int i=0;i<3;i++) {
p = c[i][k];
q = c[k][k];
for(int j=0;j<3;j++) {
if(i!=k) {
c[i][j] = c[i][j]*q-p*c[k][j];
b[i][j] = b[i][j]*q-p*b[k][j];
}}}}
for(int i=0;i<3;i++)
for(int j=0;j<3;j++) {
b[i][j] = b[i][j]/c[i][i]; }
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System.out.println("");
System.out.println("\nInverse Matrix is : ");
for(int i=0;i<3;i++) {
for(int j=0;j<3;j++)
System.out.print(b[i][j] + " ");
System.out.print("\n"); }
}}
Output:
Enter a 3 letter string: hai
Encrypted string is :fdx
Inverse Matrix is :
0.083333336 0.41666666 -0.33333334
-0.41666666 -0.083333336 0.6666667
0.5833333 -0.083333336 -0.33333334
Decrypted string is :hai
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4. Write a C/JAVA program to implement the DES algorithm logic.
AIM: To Write a Java program to implement the DES algorithm logic.
PROGRAM:
import java.util.*;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.security.spec.KeySpec;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESedeKeySpec;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
public class DES {
private static final String UNICODE_FORMAT = "UTF8";
public static final String DESEDE_ENCRYPTION_SCHEME = "DESede";
privateKeySpecmyKeySpec;
privateSecretKeyFactorymySecretKeyFactory;
private Cipher cipher;
byte[] keyAsBytes;
private String myEncryptionKey;
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private String myEncryptionScheme;
SecretKey key;
static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
public DES() throws Exception {
// TODO code application logic here myEncryptionKey = "ThisIsSecretEncryptionKey";
myEncryptionScheme = DESEDE_ENCRYPTION_SCHEME; keyAsBytes =
myEncryptionKey.getBytes(UNICODE_FORMAT); myKeySpec = new
DESedeKeySpec(keyAsBytes);
mySecretKeyFactory = SecretKeyFactory.getInstance(myEncryptionScheme);
cipher = Cipher.getInstance(myEncryptionScheme);
key = mySecretKeyFactory.generateSecret(myKeySpec);
public String encrypt(String unencryptedString)
{ String encryptedString = null;
try {
cipher.init(Cipher.ENCRYPT_MODE, key);
byte[] plainText = unencryptedString.getBytes(UNICODE_FORMAT); byte[] encryptedText =
cipher.doFinal(plainText);
BASE64Encoder base64encoder = new BASE64Encoder();
encryptedString = base64encoder.encode(encryptedText); }
catch (Exception e) {
e.printStackTrace(); }
returnencryptedString; }
public String decrypt(String encryptedString) { String decryptedText=null;
try {
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cipher.init(Cipher.DECRYPT_MODE, key);
BASE64Decoder base64decoder = new BASE64Decoder(); byte[] encryptedText =
base64decoder.decodeBuffer(encryptedString); byte[] plainText =
cipher.doFinal(encryptedText); decryptedText= bytes2String(plainText); }
catch (Exception e) {
e.printStackTrace(); }
returndecryptedText; }
private static String bytes2String(byte[] bytes)
{
StringBufferstringBuffer = new StringBuffer();
for (int i = 0; i <bytes.length; i++)
{ stringBuffer.append((char) bytes[i]); }
returnstringBuffer.toString(); }
public static void main(String args []) throws Exception
{ System.out.print("Enter the string: ");
DES myEncryptor= new DES();
String stringToEncrypt = br.readLine();
String encrypted = myEncryptor.encrypt(stringToEncrypt);
String decrypted = myEncryptor.decrypt(encrypted);
System.out.println("\nString To Encrypt: " +stringToEncrypt); System.out.println("\nEncrypted
Value : " +encrypted);
System.out.println("\nDecrypted Value : " +decrypted);
System.out.println("");
OUTPUT:
Enter the string: Welcome
String To Encrypt: Welcome
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Encrypted Value : BPQMwc0wKvg=
Decrypted Value : Welcome
5. Write a C/JAVA program to implement the Blowfish algorithm logic.
AIM: Write a C/JAVA program to implement the BlowFish algorithm logic.
PROGRAM:
import java.io.*;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.security.Key;
import javax.crypto.Cipher;
import javax.crypto.CipherOutputStream;
import javax.crypto.KeyGenerator;
import sun.misc.BASE64Encoder;
public class BlowFish {
public static void main(String[] args) throws Exception {
// TODO code application logic here KeyGeneratorkeyGenerator =
KeyGenerator.getInstance("Blowfish"); keyGenerator.init(128);
Key secretKey = keyGenerator.generateKey();
Cipher cipherOut = Cipher.getInstance("Blowfish/CFB/NoPadding");
cipherOut.init(Cipher.ENCRYPT_MODE, secretKey); BASE64Encoder encoder = new
BASE64Encoder();
byte iv[] = cipherOut.getIV(); if (iv != null) {
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System.out.println("Initialization Vector of the Cipher: " + encoder.encode(iv)); }
FileInputStream fin = new FileInputStream("inputFile.txt");
FileOutputStreamfout = new FileOutputStream("outputFile.txt");
CipherOutputStreamcout = new CipherOutputStream(fout, cipherOut);
int input = 0;
while ((input = fin.read()) != -1) {
cout.write(input); }
fin.close(); cout.close(); }}
OUTPUT:
Initialization Vector of the Cipher: dI1MXzW97oQ=
Contents of inputFile.txt: Hello World
Contents of outputFile.txt: ùJÖ˜ NåI“
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6. Write a C/JAVA program to implement the Rijndael algorithm logic.
AIM: Write a C/JAVA program to implement the Rijndael algorithm logic.
PROGRAM:
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.io.*;
public class AES {
public static String asHex (byte buf[]) {
StringBuffer strbuf = new StringBuffer(buf.length * 2); int i;
for (i = 0; i < buf.length; i++) {
if (((int) buf[i] & 0xff) < 0x10)
strbuf.append("0");
strbuf.append(Long.toString((int) buf[i] & 0xff, 16)); }
return strbuf.toString(); }
public static void main(String[] args) throws Exception { String message="AES still rocks!!";
// Get the KeyGenerator
KeyGenerator kgen = KeyGenerator.getInstance("AES"); kgen.init(128); // 192 and 256 bits may
not be available
// Generate the secret key specs.
SecretKey skey = kgen.generateKey();
byte[] raw = skey.getEncoded();
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SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
// Instantiate the cipher
Cipher cipher = Cipher.getInstance("AES"); cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
byte[] encrypted = cipher.doFinal((args.length == 0 ? message : args[0]).getBytes());
System.out.println("encrypted string: " + asHex(encrypted));
cipher.init(Cipher.DECRYPT_MODE, skeySpec);
byte[] original = cipher.doFinal(encrypted);
String originalString = new String(original);
System.out.println("Original string: " + originalString + " " + asHex(original)); } }
OUTPUT:
Initialization Vector of the Cipher: dI1MXzW97oQ
encrypted string: Hello World
Original string: as Hex
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7. Write the RC4 logic in Java Using Java cryptography; encrypt the text “Hello world”
using Blowfish. Create your own key using Java key tool.
AIM: Using Java Cryptography, encrypt the text “Hello world” using BlowFish.
Create your own key using Java keytool.
PROGRAM:
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.swing.JOptionPane;
public class BlowFishCipher {
public static void main(String[] args) throws Exception {
// create a key generator based upon the Blowfish cipher KeyGeneratorkeygenerator =
KeyGenerator.getInstance("Blowfish");
// create a key
// create a cipher based upon Blowfish Cipher cipher = Cipher.getInstance("Blowfish");
// initialise cipher to with secret key cipher.init(Cipher.ENCRYPT_MODE, secretkey);
// get the text to encrypt
String inputText = JOptionPane.showInputDialog("Input your message: "); // encrypt message
byte[] encrypted = cipher.doFinal(inputText.getBytes());
// re-initialise the cipher to be in decrypt mode cipher.init(Cipher.DECRYPT_MODE,
secretkey);
// decrypt message
byte[] decrypted = cipher.doFinal(encrypted);
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// and display the results
JOptionPane.showMessageDialog(JOptionPane.getRootFrame(), "\nEncrypted text: " + new
String(encrypted) + "\n" + "\nDecrypted text: " + new String(decrypted));
System.exit(0);
}}
OUTPUT:
Input your message: Hello world
Encrypted text: 3ooo&&(*&*4r4
Decrypted text: Hello world
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8. Write a Java program to implement RSA algorithm.
AIM: Write a Java program to implement RSA Algoithm.
PROGRAM:
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.math.*;
import java.util.Random;
import java.util.Scanner;
public class RSA {
static Scanner sc = new Scanner(System.in);
public static void main(String[] args) {
// TODO code application logic here System.out.print("Enter a Prime number: ");
BigInteger p = sc.nextBigInteger(); // Here's one prime number.. System.out.print("Enter another
prime number: "); BigInteger q = sc.nextBigInteger(); // ..and another.
BigInteger n = p.multiply(q);
BigInteger n2 = p.subtract(BigInteger.ONE).multiply(q.subtract(BigInteger.ONE)); BigInteger e
= generateE(n2);
BigInteger d = e.modInverse(n2); // Here's the multiplicative inverse
System.out.println("Encryption keys are: " + e + ", " + n);
System.out.println("Decryption keys are: " + d + ", " + n);
public static BigIntegergenerateE(BigIntegerfiofn) {
int y, intGCD;
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BigInteger e;
BigInteger gcd;
Random x = new Random();
do {
y = x.nextInt(fiofn.intValue()-1);
String z = Integer.toString(y);
e = new BigInteger(z);
gcd = fiofn.gcd(e);
intGCD = gcd.intValue();
while(y <= 2 || intGCD != 1);
return e;
OUTPUT:
Enter a Prime number: 5
Enter another prime number: 11
Encryption keys are: 33, 55
Decryption keys are: 17, 55
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9. Implement the Diffie-Hellman Key Exchange mechanism using HTML and JavaScript.
Aim: To i mplement the Diffie-Hellman Key Exchange mechanism using HTML and
JavaScript.
PROGRAM:
import java.math.BigInteger;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.SecureRandom;
import javax.crypto.spec.DHParameterSpec;
import javax.crypto.spec.DHPublicKeySpec;
public class DiffeHellman {
public final static int pValue = 47;
public final static int gValue = 71;
public final static int XaValue = 9;
public final static int XbValue = 14;
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public static void main(String[] args) throws Exception { // TODO code application logic here
BigInteger p = new BigInteger(Integer.toString(pValue)); BigInteger g = new
BigInteger(Integer.toString(gValue)); BigIntegerXa = new
BigInteger(Integer.toString(XaValue)); BigIntegerXb = new
BigInteger(Integer.toString(XbValue)); createKey();
intbitLength = 512; // 512 bits
SecureRandomrnd = new SecureRandom();
p = BigInteger.probablePrime(bitLength, rnd); g = BigInteger.probablePrime(bitLength, rnd);
createSpecificKey(p, g);
public static void createKey() throws Exception {
KeyPairGeneratorkpg = KeyPairGenerator.getInstance("DiffieHellman");
kpg.initialize(512);
KeyPairkp = kpg.generateKeyPair();
KeyFactorykfactory = KeyFactory.getInstance("DiffieHellman");
DHPublicKeySpeckspec = (DHPublicKeySpec) kfactory.getKeySpec(kp.getPublic(),
DHPublicKeySpec.class);
System.out.println("Public key is: " +kspec);
public static void createSpecificKey(BigInteger p, BigInteger g) throws Exception
{ KeyPairGeneratorkpg = KeyPairGenerator.getInstance("DiffieHellman");
DHParameterSpecparam = new DHParameterSpec(p, g); kpg.initialize(param);
KeyPairkp = kpg.generateKeyPair();
KeyFactorykfactory = KeyFactory.getInstance("DiffieHellman");
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DHPublicKeySpeckspec = (DHPublicKeySpec) kfactory.getKeySpec(kp.getPublic(),
DHPublicKeySpec.class);
System.out.println("\nPublic key is : " +kspec);
OUTPUT:
Public key is: javax.crypto.spec.DHPublicKeySpec@5afd29
Public key is: javax.crypto.spec.DHPublicKeySpec@9971ad
10. Calculate the message digest of a text using the SHA-1 algorithm in JAVA.
AIM: Calculate the message digest of a text using the SHA-1 algorithm in JAVA.
PROGRAM:
import java.security.*;
public class SHA1 {
public static void main(String[] a) {
try {
MessageDigest md = MessageDigest.getInstance("SHA1"); System.out.println("Message digest
object info: "); System.out.println(" Algorithm = " +md.getAlgorithm()); System.out.println("
Provider = " +md.getProvider()); System.out.println(" ToString = " +md.toString());
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String input = "";
md.update(input.getBytes());
byte[] output = md.digest();
System.out.println();
System.out.println("SHA1(\""+input+"\") = " +bytesToHex(output));
input = "abc";
md.update(input.getBytes());
output = md.digest();
System.out.println();
System.out.println("SHA1(\""+input+"\") = " +bytesToHex(output));
input = "abcdefghijklmnopqrstuvwxyz";
md.update(input.getBytes());
output = md.digest();
System.out.println();
System.out.println("SHA1(\"" +input+"\") = " +bytesToHex(output));
System.out.println(""); }
catch (Exception e) {
System.out.println("Exception: " +e);
public static String bytesToHex(byte[] b) {
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char hexDigit[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
StringBufferbuf = new StringBuffer();
for (int j=0; j<b.length; j++) {
buf.append(hexDigit[(b[j] >> 4) & 0x0f]);
buf.append(hexDigit[b[j] & 0x0f]); }
returnbuf.toString(); }
OUTPUT:
Message digest object info:
Algorithm = SHA1
Provider = SUN version 1.6
ToString = SHA1 Message Digest from SUN, <initialized> SHA1("") =
DA39A3EE5E6B4B0D3255BFEF95601890AFD80709 SHA1("abc") =
A9993E364706816ABA3E25717850C26C9CD0D89D
SHA1("abcdefghijklmnopqrstuvwxyz")=32D10C7B8CF96570CA04CE37F2A19D8424
0D3A89
11. Calculate the message digest of a text using the MD5 algorithm in JAVA.
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AIM: To Calculate the message digest of a text using the SHA-1 algorithm in JAVA.
PROGRAM:
import java.security.*;
public class MD5 {
public static void main(String[] a) {
// TODO code application logic here
try {
MessageDigest md = MessageDigest.getInstance("MD5"); System.out.println("Message digest
object info: "); System.out.println(" Algorithm = " +md.getAlgorithm()); System.out.println("
Provider = " +md.getProvider()); System.out.println(" ToString = " +md.toString());
String input = "";
md.update(input.getBytes());
byte[] output = md.digest();
System.out.println();
System.out.println("MD5(\""+input+"\") = " +bytesToHex(output));
input = "abc";
md.update(input.getBytes());
output = md.digest();
System.out.println();
System.out.println("MD5(\""+input+"\") = " +bytesToHex(output));
input = "abcdefghijklmnopqrstuvwxyz";
md.update(input.getBytes());
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output = md.digest();
System.out.println();
System.out.println("MD5(\"" +input+"\") = " +bytesToHex(output)); System.out.println("");
catch (Exception e) {
System.out.println("Exception: " +e); }
public static String bytesToHex(byte[] b) {
char hexDigit[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
StringBufferbuf = new StringBuffer();
for (int j=0; j<b.length; j++) {
buf.append(hexDigit[(b[j] >> 4) & 0x0f]);
buf.append(hexDigit[b[j] & 0x0f]); }
return buf.toString(); } }
OUTPUT:
Message digest object info:
Algorithm = MD5
Provider = SUN version 1.6
ToString = MD5 Message Digest from SUN, <initialized> MD5("") =
D41D8CD98F00B204E9800998ECF8427E MD5("abc") =
900150983CD24FB0D6963F7D28E17F72 MD5("abcdefghijklmnopqrstuvwxyz") =
C3FCD3D76192E4007DFB496CCA67E13B
MREM CRYTOGRAPHY AND NETWORK SECURITY P a g e | 33
MREM CRYTOGRAPHY AND NETWORK SECURITY P a g e | 34
