Course Project Book(Mobile Computing and Wireless Networks)
CS 395T – Spring 2002
Course Instructor:Dr. Yongguang Zhang ([email protected])
Course URL: http://www.cs.utexas.edu/users/ygz/395T-02S
May 17, 2002
Project List
1. Shruti : Session Migration2. Intelligent Routing Decisions in AODV3. Security in Ad-hoc Networks4. Secure Group Management in Ad-hoc Network 5. UBQuards: A Smartcard Project6. Smart Cards: Career Fair Experience7. Content Based Routing on Ad-Hoc Networks8. A New Service Discovery Protocol for MANET9. Comparison of Energy-Aware Ad-hoc Routing10. Multi-Mode TCP
A CS395T Course Project MobileComputing &
WirelessNetworks
Spring 2002C
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Design/Approach Application layer
–Application API to get/set application state Session Manager daemon
–Provides interaction between Home Agent and all user state
Home Agent–Stores the user’s session state
Socket Migrator–Uses IP redirection to offer same abstraction–Transfers TCP state
Challenges Faced, Lessons Learnt Modifications to legacy applications Maintaining portability Implementation & Integration 32-bit IP insufficient for unique PK
abstraction that combines security and authentication
Pre-publish or perish–http://www.cs.cmu.edu/~softagents/
migsock/MIGSOCK-ThesisPresentation.ppt
Shruti : Session Migration
Future work Migrate
–Other applications (mp3, ram)–User Mode Linux–Bosch virtual machine simulator
Application layer –Use condor style-checkpointing–Create new language abstractions
Home agent using smartcard
Project team:Amit, Amol, Ravi, Deepak, Divya, Young-RiURL: http://www.cs.utexas.edu/users/amitji/utOnly/Shruti.html
Application
Network level
App State
To other end host
TCP
Personal IP
IP
A CS395T Course Project MobileComputing &
WirelessNetworks
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Implementation Issues Simulated these extensions on ns-2 Experimented with varying parameters
–Optimum Beaconing Interval–Dynamically adjust wait time at destination
Performance comparison with base AODV–Used Different mobility patterns of pause time
and speeds
New Ideas Using signal strength values to predict the
link life time and hence stability of a route–Choose more stable routes
Maintaining multiple paths for a destination–Decreases route discovery latency–Reduce the effect of route failures
Intelligent Routing Decisions in AODV
Results/Lesson Learned
Project team: Gokhan Uluderya, Jared G. Boone & Ashish AhujaURL: http://www.cs.utexas.edu/users/uluderya/MWNET/project.html
Key Design/Approach Figure out how to measure life time of a
link–Use Friis law to predict the relative position of
a neighbouring node Keep a secondary routing table
–If primary route fails, use secondary route–If both routes fail, initiate route discovery
A CS395T Course Project MobileComputing &
WirelessNetworks
Spring 2002C
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Key Design/Approach Provide a broad reading list for research in
the area Leverage existing work in security for
basis of solutions Adapt existing algorithms to ad-hoc
networks Utilize existing toolkits for cryptographic
algorithms
Algorithms Implemented Password-authenticated group key
establishment Threshold cryptography shared secret
division by trusted party, then recollection by clients
Security in Ad-hoc Networks
Results/Lesson Learned Implemented in Java Used Java Cryptographic Extensions
(JCE)–Sun’s JCE provider for Triple-DES–BouncyCastle.org’s for AES and RSA
Lesson learned:–Many existing security solutions are
unsuitable due to lack of on-line server or predefined hierarchy
–We must assume a prior context
Project team: Kevin KaneURL: http://www.cs.utexas.edu/users/kane/395T-02S/
Paper Themes Surveyed Group key establishment
–Password-authenticated–Unauthenticated
Threshold cryptography–Secret sharing–Distributed cryptographic operations
Web of trust–“Introducers”
A CS395T Course Project MobileComputing &
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Spring 2002C
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Simulation Results
Secure Group Management in Ad-hoc Network
Conclusion Has clear advantage in terms of
connection time against the centralized approach.
Need further optimization to adapt frequent topology changes.
Project team: Chun-Chi Chen, Edwin Ng, Chwan-Ming WangURL: http://www.cs.utexas.edu/users/ccchen/classes/cs395t-mwc/proposal.html
Motivation Security in ad hoc networks is a necessity. Not many simulations or implementations
for security have been done in ad hoc networks.
Centralized approach is not suitable. Investigate a distributed solution for key
management.
Architecture Works on top of existing routing protocols.
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A CS395T Course Project MobileComputing &
WirelessNetworks
Spring 2002C
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Key Design/Approach Web service language interpreter
– Run as a Cardlet– 32K Javacard, Stripped down JVM– 1 input, 1 output instruction set– only integer types– control flow using predicates
Communication Module Consumer Device Web Services
– Microsoft.NET Platform, SOAP
New Ideas Specification for using smartcards as the
medium for ubiquitous web services
User state information on card– stateless web service servers
Web service workflow description
Hardware/Software specification for universal communication module
UBQuards: A Smartcard Project
Results/Lesson Learned Proof of Concept
– Smartcards + Ubiquitous– Software Implementation
Ubiquitous Communication Module– USB, HTTP/SOAP, WFDL– Smartcards Computing Power Increasing
Example Scenario– Plug-n-Play Internet Capability–Communication, Storage, “device stuff”
completely detached.
Project team: Changkyu Kim, Karu Sankaralingam, Youngin ShinURL: http://www.cs.utexas.edu/users/karu/mobile/
CM
Cardlet Device Web Service
A CS395T Course Project MobileComputing &
WirelessNetworks
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Design/Approach VB front end for sending/receiving resume Resume and BizCard in XML format
–Standardized format and parsing –Applet on smart card has a simple parser
Students have an interface to personalize the data they want from recruiter
Implementation platform:–SLB 4.1 toolkit and REFLEX 72 card reader–Metrowerks CodeWarrior IDE for debugging
and simulator on Windows 2000 platform
New Ideas Current literature focuses on the security
aspect of smart cards Exploit smartcards for personalization Saves effort and more efficient and easier
for students and recruiters Recruiters anyway have to “scan” the
resume into the database
Smart Cards: Career Fair Experience
Results and Future work Challenging to program with limited data
types and memory Developed prototype to demonstrate
simple processing on and off the card. Smart cards still not ready
–Memory too low, (use compression on host side), garbage collection (Java Card)
–Tool kit unstable and Simulator not very reliable
–Few data types, array of objects or 2-D arrays not available
Project team: Kaushik Lakshmanan and Ramanathan Pallassana
A CS395T Course Project MobileComputing &
WirelessNetworks
Spring 2002C
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Motivation Peer-to-peer applications : content driven No centralized DNS for name-lookup in
MANETs Current protocols have to decouple steps
of name to address mapping and route discovery
Combine! -- Content based routing
Content Based Routing on Ad-Hoc Networks
Results/Lesson Learned Implemented in NS2 Comparison
–Plain flooding vs Our Content-Routing–Metric
– Traffic : over 80% reduction– Route cache hit rate : about 27%– Control traffic : negligible
Lesson learned:–Think out of the box–challenge to implement a whole new protocol
in nsProject team: Vivek Subramanian & Amish Gandhi
URL: http://www.cs.utexas.edu/users/viveksub/mobile_proj.html or http://www.schmoogle.com
Key Ideas/Design Nodes maintain information if they are on
a path towards content Communication : local broadcast Associate a path-id with every path
discovered Eliminate IP-Address/node-id For optimization :use pseudo random
local-id Distance metric : hop count
1
1
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Content Routing Agent
LL
P2P App Agent
Channel
MAC
Content Requested
Reply withContent
A CS395T Course Project MobileComputing &
WirelessNetworks
Spring 2002C
ourse
we
b site
: http://w
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rs/ygz/39
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structor: D
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Motivation Service Discovery will become a crucial
need for upcoming networks/devices for seamless interoperability
Existing Protocols–JINI, UPNP, SLP, Salutation, etc..
Existing protocols are unsuitable for Mobile AdHoc Networks
We Propose and implement a new SDP for MANETs.
New Ideas Distributed directory Cache optimizations (ala DSR, AODV) Periodic Broadcast based Service
Advertisement. Transparent to underlying routing protocols Each node serves as a Service Agent,
Directory agent and also User agent
A New Service Discovery Protocol for MANET
Results/Lessons Learned File Sharing Application implemented in
java Tested using AdHoc toolkit Used Socket Library extension to emulate
the mobile environment Lessons learned:
– Using AdHoc toolkit– Various SDPs
Project team: Krupakar V. Pasupuleti, Jisun Park and Subramanyam MallelaURL: http://www.cs.utexas.edu/users/manyam/cosd.htm
MANET
Master
Slave
AdHoc Tool Kit Environment
Service Agent
Agent API
Application
A CS395T Course Project MobileComputing &
WirelessNetworks
Spring 2002C
ourse
we
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: http://w
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rs/ygz/39
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structor: D
r. Yon
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Simulation Setup Use the ns-2 simulator. Parameters: traffic load (number of source
nodes and traffic rate), mobility (pause time, speed).
Matrices: Packet delivery rate vs. traffic load, packet loss rate vs. mobility, network lifetime vs. traffic load, network lifetime vs. mobility, nodes survival percentage vs. time.
Algorithm Span: Only “coordinator” nodes stay
awake. The “non-coordinator” nodes go to sleep.
Afeca: Sleep depending on the number of transmitting neighbors.
FA: Choose the minimum cost routing path.
DSR
Comparison of Energy-Aware Ad-hoc Routing
Results/Lesson Learned
Project team: Pisai Setthawong, Hari Shankar, Yihong ZhouURL: http://www.ece.utexas.edu/~pisai/cs395t
Motivation Important to ensure battery-operated
mobile nodes operate as long as possible. Several solutions proposed and compared
with non-energy-aware protocols. Our goal is to compare different solutions
under DSR using same parameters.
A CS395T Course Project MobileComputing &
WirelessNetworks
Spring 2002C
ourse
we
b site
: http://w
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rs/ygz/39
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structor: D
r. Yon
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Experiment Result
MM-TCP
When the bandwidth of bottlenet changes frequently, TCP can save a subset of current TCP states (mode).
When TCP return to a history network enviorment, it can use the saved mode to set some initial values, such as cwnd.
TCP can adapt the enviorment quickly and then improve the performance.
Multi-Mode TCP
Conclusion/Lesson Learned
Implemented in ns2 Simulation results in ns2
–There are some improvements when TCP switches between different network enviorment. But the improvement is not large enough.
Lesson learned:– Implementation of TCP stack–Simulation an evaluation
Project team: Yi LiURL: http://www.cs.utexas.edu/users/ylee/project.html
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Contact
Prof. Yongguang ZhangDept. of Computer SciencesUniversity of Texas at AustinAustin, Texas 78712, U.S.A.
E-mail: [email protected]: 512-232-7889