Resource Sharing of Portable Computers Using Wireless Communication

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Resource Sharing of Portable Computers Using
Wireless Communication
By Christine Meyer
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Outline

• Routing Protocols
• Load Balancing Techniques
• Cluster Computing Software
• Wireless Security Attacks
• Conclusion

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Wireless Adhoc Mode
Peer-to-Peer Communication
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Wireless Infrastructure Mode
Communication through Access Point
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Direct Sequence Spread Spectrum (DSSS)
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Wireless Range
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Routing Protocols

• Dynamic Source Routing (DSR)
• Destination Sequence Distance Vector (DSDV)
• Temporary-Ordered Routing Algorithm (TORA)
• Ad Hoc On-Demand Distance Vector (AODV)

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Comparison of Routing Protocols
Packet Delivery Ratio
Routing Overhead
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Diffusive Load Balancing on Domain
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Windows Management Instrumentation
Namespace root\WMI for signal strength
root\CIMV2 for LB information
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Cluster Computing Software
Server
Resource Manager
Display Manager
Client
Job Manager
Client Manager
Application
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Wireless Network Display
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Client to Server Routing 1
Routing A
Routing A
Client A
Server
Client B
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Client to Server Routing 2
Routing to Server
Client A
Routing A, B
Server
Routing A, B
Client B
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Encryption using Java
import javax.crypto. import javax.crypto.spec.
import java.security. SecretKey key
KeyGenerator.getInstance("DESede").generateKey()
byte keyBytes new byte
107,127,4,115,-23,55,93,47,
-36,-105, -26, 4, 38, -83,-29, 62,
107,127,4,115,-23,55,93,47 try
SecretKey key new SecretKeySpec(keyBytes,
"DESede") Cipher ecipher
Cipher.getInstance("DESede")
ecipher.init(Cipher.ENCRYPT_MODE, key) //
Seal (encrypt) the object s1 new
SealedObject(mat1, ecipher) s2 new
SealedObject(mat2, ecipher) catch (Exception
e)
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Decryption with Java
byte keyBytes new byte
107,127,4,115,-23,55,93,47,
-36,-105, -26, 4, 38, -83,-29, 62,
107,127,4,115,-23,55,93,47 try SecretKey
key new SecretKeySpec(keyBytes, "DESede")
Cipher dcipher Cipher.getInstance("DESede")
dcipher.init(Cipher.DECRYPT_MODE, key) //
Unseal (decrypt) the class a
(Matrix)s1.getObject(dcipher) b
(Matrix)s2.getObject(dcipher) catch
(Exception e)
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Java Transformation String

• Algorithm
• AES, Blowfish, DES, DESede, RSA, RC2, RC4, RC5
• Mode
• None, CBC (Cipher Block Chaining),
• CFB (Cipher Feedback Mode),
• ECB (Electronic Codebook),
• OFB (Output Feedback Mode),
• PCBC (Propagating Cipher Block Chaining)
• Padding
• No Padding,
• PKCS5Padding
• SSL3Padding
• Default DES/CBC/PKCS5Padding (64 bits to 128
  bits)
• DES 64 bits to 64 bits
• transform "DES/ECB/NoPadding

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Passive attacks to decrypt traffic
Access Point
Destination
Packet 1 XOR Packet 2 Plaintext
Eavesdropper
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Active attack to inject new traffic
Access Point
Destination
RC4(X) XOR X XOR Y RC4(Y)
Eavesdropper
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Active attacks to decrypt traffic
Decrypted Message
Decrypted Message
Access Point
Internet
Eavesdroppers Computer
Encrypted Message
Eavesdropper
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Table based Attack
Access Point
Destination
Eavesdropper
Table of IV and Key Streams
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WPA Denial of Service Attack
WPA can shutdown the system if it receives two
failed packets within a one-second period Wi-Fi
Encryption Fix Not Perfect http//www.wired.com/ne
ws/business/0,1367,56350,00.html
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Conclusion

• It is possible to improve performance through
  resource
• sharing of portable computers
• In the future, the transfer rate for wireless
  will be
• greater therefore reducing transfer time
• Security is provided for access points but not
  for
• ad-hoc mode
• Encryption is possible through Java with a small
• overhead factor