This document describes a mobile authentication and key exchange protocol that uses nested one-time secrets. It contains modules for the user, VLR verification, HLR verification, key generation, and nested one-time secrets. The protocol uses lightweight public key cryptography and a challenge-response technique in two stages: an initial procedure and real execution stage. This allows for fast mutual authentication and agreement of a nested one-time secret while providing greater security and lower computational complexity than other wireless authentication schemes.

1. Provably Secure Nested One-Time Secret Mechanisms for Fast
Mutual Authentication and Key Exchange in Mobile
Communications
Modules:
· User
· VLR Verification
· HLR Verification
· Key Generation
· Nested one-time secret
· Secure Mobile Communication
User:
In this module to send data with create one time secret key and then use symmetric encryption
key and “challenge-response” techniques were adopted to build their protocol. To implement the
fast mutual authentication and Nested one-time secret agreement, the proposed protocol contains
two stages: namely initial procedure and real execution stage. Since the lightweight public key
cryptography is employed, their protocol can not only overcome the security flaws of secret-key
based authentication protocols such as those used in Global System for Mobile Communications
(GSM) and Universal Mobile Telecommunications System, but also provide greater security and
lower computational complexity in comparison with currently well-known public key based
wireless authentication schemes.

2. VLR Verification
This module receive client key then store hash table and also receive client request then check
client key. That key is same the server give the response otherwise disconnect our
communication state. This module watch client communication area location any changes this
location automatically disconnect the communication state. This module gets current date time
and also a user identity then send to the HLR.
Screen Shots:

8. Main Form:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Security.Cryptography;
using System.Threading;
using RSACryptoPad;
using System.Net.Sockets;
using System.Runtime.Serialization.Formatters.Binary;
using System.Net;
using ChatClient;
namespace User
{
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
}
//
//RANDOM NUMBER AND DELEGATES DECLARATION
//
public static string VLR_IpAddress;
public static int currentKeyValue = 0;
public static int currentRandomNumber = 0;

9. public delegate void FinishedProcessDelegate();
public delegate void UpdateBitStrengthDelegate(int bitStrength);
public delegate void UpdateTextDelegate(string inputText);
private string publicAndPrivateKeys;
private string fileString,ServerKey;
//
//NETWORK RELATED DECLARATION
//
private NetworkStream stream2User;
private BinaryFormatter StreamBinaryUser;
private TcpClient UserTcpClient;
//
//LOCAL STRING DECLARATION
//
private Thread t1,UserListern;
private bool connected;
string Key;
private int RandomNumber,CheckRandomNumber;
string EncryptFile;
private void decriptionToolStripMenuItem_Click(object sender,
EventArgs e)
{
}
public static void Key_Value(int Value)
{
currentKeyValue = Value;
}
private void FinishedProcess()
{
Application.DoEvents();
}
private void UpdateText(string inputText)
{
rtxtbDisplay.Text = inputText;
EncryptFile = inputText.ToString();
}
public static void Random_Number(int RandomValue)
{
currentRandomNumber = RandomValue;
}
private void keyGenerateToolStripMenuItem_Click(object sender,
EventArgs e)
{
if (currentKeyValue!=0||currentRandomNumber!=0)
{

10. MessageBox.Show("Already Generate Key And Number ",
"TimeStamp Based Approach", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
else
{
KeyGenerator obj = new KeyGenerator();
obj.ShowDialog();
}
}
public static void Ip_Address(string VLR_Ip_Address)
{
VLR_IpAddress = VLR_Ip_Address;
}
private void iFormPanel1_Paint(object sender, PaintEventArgs e)
{
//txtSend.Text = currentKeyValue.ToString();
if (rtxtbDisplay.Text.Length > 2)
{
}
else
{
rtxtbDisplay.Text = currentRandomNumber.ToString();
txtUserRandomNumber.Text = currentRandomNumber.ToString();
txtUserKey.Text = currentKeyValue.ToString();
}
}
//Key Generate Method
public void KeyGenerate()
{
RSACryptoServiceProvider RSAProvider = new
RSACryptoServiceProvider(currentKeyValue);
publicAndPrivateKeys = "<BitStrength>" +
currentKeyValue.ToString() + "</BitStrength>" + RSAProvider.ToXmlString(true);
fileString = publicAndPrivateKeys.ToString();
}
//Create Encription Method
public void Encryption()
{
if (fileString != null)
{
FinishedProcessDelegate finishedProcessDelegate = new
FinishedProcessDelegate(FinishedProcess);
UpdateTextDelegate updateTextDelegate = new
UpdateTextDelegate(UpdateText);
string bitStrengthString = fileString.Substring(0,
fileString.IndexOf("</BitStrength>") + 14);
fileString = fileString.Replace(bitStrengthString, "");
int bitStrength =
Convert.ToInt32(bitStrengthString.Replace("<BitStrength>",
"").Replace("</BitStrength>", ""));
if (fileString != null)

11. {
try
{
EncryptionThread encryptionThread = new
EncryptionThread();
Thread encryptThread = new
Thread(encryptionThread.Encrypt);
encryptThread.IsBackground = true;
encryptThread.Start(new Object[] { this,
finishedProcessDelegate, updateTextDelegate, rtxtbDisplay.Text, bitStrength,
fileString });
}
catch (CryptographicException CEx)
{ MessageBox.Show("ERROR: nOne of the following has
occured.nThe cryptographic service provider cannot be acquired.nThe length
of the text being encrypted is greater than the maximum allowed length.nThe
OAEP padding is not supported on this computer.n" + "Exact error: " +
CEx.Message); }
catch (Exception Ex)
{ MessageBox.Show("ERROR: n" + Ex.Message); }
}
}
}
private void encriptionToolStripMenuItem_Click(object sender,
EventArgs e)
{
if (rtxtbDisplay.Text.Length > 3)
{
if (currentKeyValue == 0 || currentRandomNumber == 0)
{
MessageBox.Show("RandomNumber And Key values are NULL",
"TimeStamp Based Approach", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
else
{
if (EncryptFile != null)
{
MessageBox.Show("Encryption Already Created",
"TimeStamp Based Approach", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
else
{
//Call Key Generation Method
KeyGenerate();
//Call Encryption Method
Encryption();
}
}
}
else
{
MessageBox.Show("Encryption Fields Are Empty", "User_Form",
MessageBoxButtons.OK, MessageBoxIcon.Information);
}

12. }
private void iFormGlassButton5_Click(object sender, EventArgs e)
{
RSACryptoServiceProvider RSAProvider = new
RSACryptoServiceProvider(currentKeyValue);
string publicAndPrivateKeys = "<BitStrength>" +
currentKeyValue.ToString() + "</BitStrength>" + RSAProvider.ToXmlString(true);
string fileString = publicAndPrivateKeys.ToString();
if (fileString != null)
{
FinishedProcessDelegate finishedProcessDelegate = new
FinishedProcessDelegate(FinishedProcess);
UpdateTextDelegate updateTextDelegate = new
UpdateTextDelegate(UpdateText);
string bitStrengthString = fileString.Substring(0,
fileString.IndexOf("</BitStrength>") + 14);
fileString = fileString.Replace(bitStrengthString, "");
int bitStrength =
Convert.ToInt32(bitStrengthString.Replace("<BitStrength>",
"").Replace("</BitStrength>", ""));
if (fileString != null)
{
try
{
EncryptionThread encryptionThread = new
EncryptionThread();
Thread encryptThread = new
Thread(encryptionThread.Encrypt);
encryptThread.IsBackground = true;
encryptThread.Start(new Object[] { this,
finishedProcessDelegate, updateTextDelegate, rtxtbDisplay.Text, bitStrength,
fileString });
}
catch (CryptographicException CEx)
{ MessageBox.Show("ERROR: nOne of the following has
occured.nThe cryptographic service provider cannot be acquired.nThe length
of the text being encrypted is greater than the maximum allowed length.nThe
OAEP padding is not supported on this computer.n" + "Exact error: " +
CEx.Message); }
catch (Exception Ex)
{ MessageBox.Show("ERROR: n" + Ex.Message); }
}
}
}
private void Listen()
{
while (connected == true)
{
}
}

13. private void sendToolStripMenuItem_Click(object sender, EventArgs e)
{
Ip_Address obj = new Ip_Address();
obj.Hide();
obj.ShowDialog();
if (currentKeyValue == 0 || currentRandomNumber == 0)
{
MessageBox.Show("Generate Random Number And Key", "TimeStamp
Based Approach", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
else
{
if (EncryptFile == null)
{
MessageBox.Show("Encrypt First then select Send",
"TimeStamp Based Approach", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
else
{
Key = fileString.ToString();
RandomNumber = currentRandomNumber;
string ipaddress = VLR_IpAddress;
int portnumber = 7000;
if (connected == false)
{
try
{
StreamBinaryUser = new BinaryFormatter();
UserTcpClient = new TcpClient(ipaddress,
portnumber);
stream2User = UserTcpClient.GetStream();
StreamBinaryUser.Serialize(stream2User,
publicAndPrivateKeys);
StreamBinaryUser.Serialize(stream2User,
RandomNumber);
StreamBinaryUser.Serialize(stream2User,
EncryptFile);
stream2User.Close();
UserTcpClient.Close();
}
catch (Exception ex)
{
MessageBox.Show("Destination Has been Off_Mode Or
Wrong Ip_Address","User
Send",MessageBoxButtons.OK,MessageBoxIcon.Information);
}
}
}
}

14. }
private void iFormGlassButton1_Click(object sender, EventArgs e)
{
}
private void clearToolStripMenuItem_Click(object sender, EventArgs e)
{
currentKeyValue = 0;
currentRandomNumber = 0;
EncryptFile = null;
rtxtbDisplay.Text = "";
}
private void MainForm_Load(object sender, EventArgs e)
{
checkToolStripMenuItem.Enabled = false;
chatToolStripMenuItem.Enabled = false;
UserListern = new Thread(new
System.Threading.ThreadStart(User_Recieve)); // Start Thread Session
UserListern.Start();
}
public void User_Recieve()
{
TcpListener ListernReciever = new TcpListener(IPAddress.Any,
8000);
ListernReciever.Start();
Socket UserSocket = ListernReciever.AcceptSocket();
NetworkStream UserStream = new NetworkStream(UserSocket);
BinaryFormatter UserFormater = new BinaryFormatter();
Control.CheckForIllegalCrossThreadCalls = false;
object UserRandomNumber, UserKey, ServerEncryptFile,
ServerSessionKey;
UserRandomNumber = UserFormater.Deserialize(UserStream);
UserKey = UserFormater.Deserialize(UserStream);
ServerEncryptFile = UserFormater.Deserialize(UserStream);
ServerSessionKey = UserFormater.Deserialize(UserStream);
UserStream.Close();
//UserSocket.Close();
ListernReciever.Stop();
CheckRandomNumber = int.Parse(UserRandomNumber.ToString());
ServerKey = ServerSessionKey.ToString();
checkToolStripMenuItem.Enabled = true;
if (UserSocket.Connected == true)
{
while (true)
{
User_Recieve();
}
}
}

15. private void chatToolStripMenuItem_Click(object sender, EventArgs e)
{
Form1 obj = new Form1(ServerKey);
obj.ShowDialog();
}
private void checkToolStripMenuItem_Click(object sender, EventArgs e)
{
if (CheckRandomNumber == int.Parse(txtUserRandomNumber.Text))
{
chatToolStripMenuItem.Enabled = true;
MessageBox.Show("Server is Authenticated", "User Node",
MessageBoxButtons.OK, MessageBoxIcon.Information);
txtReturnRandomNumber.Text =
Convert.ToString(CheckRandomNumber);
}
else
{
MessageBox.Show("Server Not Authenticated", "User Node",
MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
}
}
Ip_Address:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace User
{
public partial class Ip_Address : Form
{
public Ip_Address()
{
InitializeComponent();
}
private void Ip_Address_Load(object sender, EventArgs e)
{
}
private void btnSend_Click(object sender, EventArgs e)
{
if (txtIpAddress.Text.Length > 0)
{
User.MainForm.Ip_Address(txtIpAddress.Text);

16. this.Dispose(true);
}
else
{
MessageBox.Show("Give Ip_Address then Click Send",
"Ip_Address Form", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
}
}
Key Generation Form:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;
namespace User
{
public partial class KeyGenerator : Form
{
public KeyGenerator()
{
InitializeComponent();
}
Connection_String obj = new Connection_String();
private void btnKeyGenerate_Click(object sender, EventArgs e)
{
User.MainForm.Key_Value(Convert.ToInt32(numericUpDown1.Value));
}
private void btnRandomNumber_Click(object sender, EventArgs e)
{
Random obj = new Random();
txtRandomNumber.Text =Convert.ToString(obj.Next());
User.MainForm.Random_Number(Convert.ToInt32(txtRandomNumber.Text));
//this.DialogResult = DialogResult.OK;
}
private void btnSetandExit_Click(object sender, EventArgs e)
{
try
{
SqlConnection sqlcon = new SqlConnection(obj.con);

17. SqlCommand cmd = new SqlCommand("insert into UserTable
values('"+numericUpDown1.Value.ToString()+"','"+txtRandomNumber.Text+"')",
sqlcon);
sqlcon.Open();
cmd.ExecuteNonQuery();
sqlcon.Close();
this.Dispose(true);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message.ToString());
}
}
}
}
Methods of Salving Problem:
Hwang and Chang proposed a mutual authentication scheme for mobile communications, which
is briefly described below. First, the notation used in the scheme is defined in Table I.
The scheme consists of two protocols. The first one is described below.