The document describes a presentation on implementing threshold proxy re-encryption and decentralized erasure code for distributed storage systems. The proposed system uses threshold proxy re-encryption and decentralized erasure coding to improve security and reliability compared to traditional general encryption schemes. Key components include storage servers, key servers, and flexible adjustment of parameters between servers. Diagrams are included showing the system architecture, workflow, use cases and sequences.

1. Presentation By
Rupera Priyank Anilkumar 1AM09IS052
Vineet Kumar 1AM09IS074
Ajay Kumar Yadav 1AM09IS004
Krishna Kumar 1AM06IS029
Under the Guidance of
Mrs. V . Rose Priyanka
Asst.Prof, Dept of ISE

2. Content
 Abstract
 Existing System
 Demerits
 Proposed System
 Architecture
 Merits
 Functional Requirements
 Non Functional Requirements
 System Design
 Screen Shots
 References

3. Abstract
 Implementing threshold proxy re-encryption and decentralized
erasure code.
 Distributed storage System used for distribution purpose, and it
depends on the secure storage system.
 Storage server and key server are used.
 Parameters are more flexible adjustment between
servers(storage and key).

4. Existing System
 General encryption scheme for storing data.
 DES algorithm is used for key generation.
 For the storage data ,user has to manage his keys .
 Single storage server for whole file.

5. Demerits
 Communication traffic between the user and storage servers.
 User’s device of storing the keys is lost.
 Storing and retrieving, it is hard for storage servers .
 Only one time encryption using general encryption schemes.

6. Proposed System
 The method of threshold proxy re-encryption.
 Decentralized erasure code method can be used for distributed
storage system.
 Distributed storage system depends on the secure cloud
storage.
 Storage server and key server those two systems used for
storage system.
 Encryption using Blowfish algorithm.

7. Architecture

8. Merits
 Data is more confidential.
 Highly protected by an security mechanism of the Server
 Easy distribution and data forwarding.
 Less Time consuming.

9. Functional Requirement
 Encryption
 Re-encryption
 Storage
 Decryption

10. Non Functional Requirement
 Privacy
 Reliability
 Scalability
 Performance
 Security

11. System Design
 Workflow Diagram
A workflow diagram visually represents the movement and transfer of
resources, documents, data and tasks through the entire work process for a
given product or service.
 Use case Diagram
Use case diagrams are used to describe a set of actions use cases that
some system or systems subject should or can perform in collaboration with
one or more external users of the system actors.
 Sequence Diagram
A sequence diagram is a kind of interaction diagram that shows how
processes operate with one another and in what order.

12. Workflow Diagram

13. Use Case Diagram

14. Sequence Diagram
Login Register Home File select
jButtonActionPerformed
Register to cloud
jButtonActionPerformed
Select file for encryption
Encryption
jButtonActionPerformed
jButtonActionPerformed
jButtonActionPerformed

15. Continue…
Re-encryptionSplitting
Select No. of tokens
jButtonActionPerformed
Upload file
jButtonActionPerformed
Select VM1 and VM2
Retrieve
jButtonActionPerformed
Receiving from
VM1 and VM2
Decryption
jButtonActionPerformed

16. Modules
 Process Encryption
 Threshold-Proxy Function
 Secure Cloud Storage
 Data Forwarding

17. Login and Registration

18. Encryption Process

20. // Creation of Secret key
byte key[] = "HUFEdcba".getBytes();
String k = key.toString();
SecretKeySpec secretKey = new SecretKeySpec(key, "Blowfish");
// Creation of Cipher objects
Cipher encrypt = Cipher.getInstance("Blowfish");
encrypt.init(Cipher.ENCRYPT_MODE, secretKey);
// Open the Plaintext file
cis = new CipherInputStream(fis, encrypt);
// Write to the Encrypted file
byte[] b = new byte[1024];
int i = cis.read(b);
while (i != -1) {
fos.write(b, 0, i);
i = cis.read(b); }
fos.flush();
fos.close();
cis.close();
fis.close();
String fenc = " File Encrypted ";
JOptionPane.showMessageDialog(null, fenc);
count++;
Coding

21. Splitting Process

22. Threshold Proxy Re-encryption Scheme
// Creation of Secret key
byte key[] = "abcdEFUH".getBytes();
SecretKeySpec secretKey = new
SecretKeySpec(key,"Blowfish");
// Creation of Cipher objects
Cipher encrypt = Cipher.getInstance("Blowfish");
encrypt.init(Cipher.ENCRYPT_MODE,
secretKey);

23. Selecting Servers For Files

24. Secure Cloud Storage

25. Server Side File Receiving

26. int bytesRead;
int current = 0;
ServerSocket serverSocket = null;
serverSocket = new ServerSocket(7777);
while(true) {
Socket clientSocket = null;
clientSocket = serverSocket.accept();
InputStream in = clientSocket.getInputStream();
OutputStream output = new
FileOutputStream("C:/"+filename+".zip");
byte[] buffer = new byte[1024];
while ((bytesRead = in.read(buffer)) != -1) {
output.write(buffer, 0, bytesRead);
}
Coding

28. try
{
Socket sock1 = new Socket("192.168.0.154", 7777);
// sendfile
File myFile = zipFile1;
System.out.println(zipFile1);
byte[] mybytearray = new byte[(int) myFile.length()];
FileInputStream fis = new FileInputStream(myFile);
BufferedInputStream bis = new BufferedInputStream(fis);
bis.read(mybytearray, 0, mybytearray.length);
OutputStream os = sock1.getOutputStream();
os.write(mybytearray, 0, mybytearray.length);
os.flush();
sock1.close();
String sen="Files are forwarded to cloud Storage server 1 !!!";
JOptionPane.showMessageDialog(null,sen);
jTextArea1.append("Sending File:"+z1);
jTextArea1.append("Files are forwarded to cloud Storage server 1 !!!");
}
catch(Exception e)
{
System.out.println("Exception : "+e);
}
Coding

29. File Retrieval Process

30. try
{
int bytesRead;
int current = 0;
ServerSocket serverSocket1 = new ServerSocket(4000);
while(true) {
Socket clientSocket = serverSocket1.accept();
InputStream in = clientSocket.getInputStream();
String op="D:/secure/server1/server1.zip";
OutputStream output = new FileOutputStream(op);
//jTextArea1.append("Received File Location from
Server1:"+output);
byte[] buffer = new byte[1024];
while ((bytesRead = in.read(buffer)) != -1) {
output.write(buffer, 0, bytesRead);
}
in.close();
output.close();
String ip2="192.168.1.2";
jTextArea1.append(" Server1 IP Address:"+ip2);
jTextArea1.append("Received File Location from Server
2:"+op);
String fr=" File can be Received from Server1.";
JOptionPane.showConfirmDialog(null,fr);
serverSocket1.close();
}
Client Sending Filename
Cipher

31. Cipher Cipher

32. try
{
Socket sock = new Socket("192.168.1.2",4000); //client IP address
jTextArea1.append("n Client IP :"+sock);
// sendfile
String fn= "D:"+reqfile1+".zip";
File myFile = new File(fn);
jTextArea1.append("n File location :"+myFile);
byte[] mybytearray = new byte[(int) myFile.length()];
jTextArea1.append("n File Length :"+mybytearray);
FileInputStream fis = new FileInputStream(myFile);
BufferedInputStream bis = new BufferedInputStream(fis);
bis.read(mybytearray, 0, mybytearray.length);
OutputStream os = sock.getOutputStream();
os.write(mybytearray, 0, mybytearray.length);
os.flush();
String sen="Files are forwarded to Client !!!";
JOptionPane.showMessageDialog(null,sen);
os.close();
sock.close();
}
Coding

33. Cipher
Server Sending Files to Client

34. try
{ Socket sock = new Socket("192.168.1.2",4000); //client IP address
jTextArea1.append("n Client IP :"+sock);
// sendfile
String fn= "D:"+reqfile1+".zip";
File myFile = new File(fn);
jTextArea1.append("n File location :"+myFile);
byte[] mybytearray = new byte[(int) myFile.length()];
jTextArea1.append("n File Length :"+mybytearray);
FileInputStream fis = new FileInputStream(myFile);
BufferedInputStream bis = new BufferedInputStream(fis);
bis.read(mybytearray, 0, mybytearray.length);
OutputStream os = sock.getOutputStream();
os.write(mybytearray, 0, mybytearray.length);
os.flush();
String sen="Files are forwarded to Client !!!";
JOptionPane.showMessageDialog(null,sen);
os.close();
sock.close();
}
catch(Exception e)
{
System.out.println("Exception : "+e);
}
Coding

36. try {
String sourcefile = "D:/secure/server1/server1.zip";
File sf=new File(sourcefile);
if (!sourcefile.endsWith(".zip")) {
System.out.println("Invalid file name!");
System.exit(0);
} else if (!new File(sourcefile).exists()) {
System.out.println("File not exist!");
System.exit(0);
}
ZipInputStream in =new ZipInputStream(new FileInputStream(sourcefile));
ZipFile zf = new ZipFile(sourcefile);
int a = 0;
for (Enumeration em = zf.entries(); em.hasMoreElements();) {
String targetfile = em.nextElement().toString();
ZipEntry ze = in.getNextEntry();
out = new FileOutputStream("D:/secure/EXTRACT/" + targetfile);
byte[] buf = new byte[1024];
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
} a = a + 1;
}
if (a > 0) {
JOptionPane.showMessageDialog(null, "Files are unzipped, click NEXT");
jTextArea1.append("nServer1 Files can be Extractedn");
jTextArea1.append("ZipFile Name:"+sf.getName()+"n");
jTextArea1.append("ZipFile size :"+sf.length()+"n");
String fol="D:/secure/EXTRACT";
File folder=new File(fol);
jTextArea1.append("n Files in the Path:n"+folder.getAbsolutePath());
}
out.close();
in.close();
}

37. try { String p=a;
String s11="plaintxt"+l;
String s12="des"+l;
String key1 ="AbCd124"+l;
l++;
File kkk=new File(p);
BufferedReader br=new BufferedReader(new FileReader(kkk));
jTextArea1.append("nnGiven File Name is:"+kkk.getName()+"n");
System.out.println("Given File Name is:"+kkk.getName()+"n");
jTextArea1.append("Given File size is:"+kkk.length()+"n");
System.out.println("Given File size is:"+kkk.length()+"n");
File dec= new File("D:/secure/firstDEcryption/"+s11+".txt");
FileInputStream fis = new FileInputStream(p);
FileOutputStream fos = new FileOutputStream(dec);
CipherOutputStream cos = null;
jTextArea1.append("Decrypted File Name is:"+dec.getName()+"n");
System.out.println("Decrypted File Name is:"+dec.getName()+"n");
jTextArea1.append("Decrypted File Path is:"+dec.getAbsolutePath()+"n");
jTextArea1.append("Key To Decrypt the cipher Text:"+key1);
System.out.println("Decrypted File Path is:"+dec.getAbsolutePath()+"n");
// Creation of Secret key
byte key[] = "abcdEFUH".getBytes();
SecretKeySpec secretKey = new SecretKeySpec(key,”Blowfish");
// Creation of plain objects
Cipher decrypt = Cipher.getInstance("DES");
decrypt.init(Cipher.DECRYPT_MODE, secretKey);
// Open the ciphert file
CipherInputStream cis=new CipherInputStream(fis, decrypt);
// Write to the decrypted file
byte[] b = new byte[1024];
int i = cis.read(b);
while (i != -1) {
fos.write(b, 0, i);
i = cis.read(b);
}
fos.flush();
fos.close();
cos.close();
fis.close();
}

38. try{
int j;
/** Takes all files in a specified directory and merge them
together...*/
File firstDEcryption = new File("D:/secure/firstDEcryption/");
listOfFiles = firstDEcryption.listFiles();
for( j=0; j<listOfFiles.length; j++){
String lines;
String srcFile = listOfFiles[j].getPath();
outFile = "D:/secure/merging.txt";
of=new File(outFile);
BufferedReader inFile=new BufferedReader(new FileReader(new
File(srcFile)));
BufferedWriter outPut=new BufferedWriter(new
FileWriter(outFile, true));
String fil=listOfFiles.toString();
jTextArea1.append("Files to be Merged:"+fil);
jTextArea1.append("Merged File Path:"+outFile);
while((lines=inFile.readLine()) != null) {
outPut.write(lines);
outPut.newLine();
}
String fenc=" Files can be Merged ";
JOptionPane.showMessageDialog(null, fenc);
outPut.flush();
outPut.close();
inFile.close();
} }

39. Re-Decryption Process

40.  Integrated a newly proposed threshold proxy re-encryption
scheme and erasure codes over exponents.
 The threshold proxy Re-encryption scheme supports encoding,
forwarding, and partial decryption operations in a distributed
way.
 By using the threshold proxy re-encryption scheme, we
present a secure cloud storage system that provides secure data
storage and secure data forwarding functionality in a
decentralized structure.
 key servers act as access nodes for providing a front-end layer
such as a traditional file system interface.
Conclusion

41. References
 IEEE 2012 paper on Distributed and Parallel systems, “A secure
Erasure code based Cloud storage System with Secure Data
forwarding”.
 Swings (second Edition) By Matthew robinson and Pavel
vorobiev.
 www.youtube.com
 Fast Software Encryption, Cambridge Security Workshop
Proceedings (December 1993), Springer-Verlag, 1994, pp. 191-
204. IEEE Paper.