Transcript Secure Key Agreement for Group Communication Team A

Secure Key Agreement for Group
Communication
A Team
Eric Olson
Will Asche
Dan Kaplan
Anthony Spring
Girish Sarma
Outline
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Current Framework
Key agreement protocol
Goals accomplished
Goals not accomplished
Assumptions
Limitations
Problems
What we learned
Future works
Conclusion
Current Framework
Application
KAP
PROXY
M2MI
M2MP
Secure Key Agreement Protocol
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Communication among group members
privately and securely, since all the
messages reach every one present in the
network
Each device contribute to the generation of a
common group key for communication
Goals accomplished
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Secure communication
Dynamic join & leave of devices
Join multiple groups simultaneously
An attacker cannot gain any information from
the underlying broadcast network
Working example applications
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Simple command line chat interface
An IRC like application
Goals not accomplished
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Devices disappearing without notice*
Authenticate nodes and IC
Make the implementation more scalable
Reliable communication
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JRMS, TCP/IP
Assumptions
Trusted members
 Trusted third party, Information Center (IC)
 All devices can see every one present in the current
network
 The new member has extra computational burden
when joining
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Limitations
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Scalability limitations
Cannot send large objects
Propagation delays
Problems
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Slow start up of IC when using large prime
numbers.
Inability to add Java crypto library’s
implementation of asymmetric key encryption
Dependency on the implementation layer to
discover other devices in the network
Analysis
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lg n messages for every member join/leave
n + lg n memory consumption
Use of stream cipher requires less
computational power, but less secure than
block ciphers
\/\/|_|7 vv3 13@4l\l3|)?
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M2MI – M2MP
The protocol
Basics of cryptography
If we had 10 more weeks…
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Handle devices disappearing
Error checking & handling
Reliable multicast
More applications
More optimizations
Conclusions
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M2MP & M2MI were sufficient for obtaining
the minimal requirements specified by the
protocol
This protocol is not practical for ad-hoc
networks
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Authentication is dependent upon unique ids,
such as MAC / IP addresses
Remote event synchronization is dependent on
reliable multicast
Conclusions
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E-moo
tabs are evil
GROUPED == GROUPSTARTUP !!!
if( left ) return left
else return left
System.err.println (“what the F***2 ?!?!!!!!”);
Don’t double lock files