CS 265 PROJECTCS 265 PROJECT
Secure Routing in Wireless Sensor Networks : Directed Diffusion a
study
Ajay Kalambur
IntroductionIntroduction
Array of sensors deployed to monitor real time events
The concepts derived from adhoc networks
Much more energy starved than adhoc networks
Sensor nodes limited battery and memory
Introduction(contd)Introduction(contd)
Scalability Self Organization Data Collection , aggregation and
processing All protocols must be designed such
that they are energy efficient
NETWORK ARCHITECTURE(My project)NETWORK ARCHITECTURE(My project)
CLUSTERS OF SENSOR NODES
LOCAL BASESTATION
LOCAL BASESTATION
Sensor Node ArchitectureSensor Node Architecture
Power Unit(Battery)
Location finding system
TransceiverSensor ADC
SensingUnit
ProcessingUnit
Processor
Storage
Directed DiffusionDirected Diffusion
Data centric , interest-based routing protocol
Base station or sink node disseminates interest
Gradient established in opposite direction for data flow
Positive and Negative Reinforcements possible
Interests also stored in interest cache at each node
Example Interest from Base station Example Interest from Base station or sink nodeor sink node Type=toxin Interval=1s //send every second Duration=50 seconds //for next 50 seconds Rect=[-100,100,250,300]
Response from sensor node Response from sensor node detecting the eventdetecting the event Type=toxin Instance=mercury Location=[120,225] Intensity=0.6 Confidence=0.7 Timestamp=03:14:45
Attacks on Directed DiffusionAttacks on Directed Diffusion
Denial of Service -jammingModification and spoofing of
routing infoDropping or selective
forwarding of data
Dropping or selective forwarding Dropping or selective forwarding of dataof data Previous attack enables malicious node to
get into path of data flow The spoofed positive and negative
reinforcements and spoofed data, Selective forwarding is trivial to achieve
Dropping all packets- similar to node being non existent.
Selective forwarding is a more dangerous security issue
COUNTERMEASURESCOUNTERMEASURES
Link layer security with each node sharing a unique key with base station
Efficient Symmetric key cryptographic schemes needed
Public key cryptography not possible Defense against internal attacks is very
challenging Routing protocol needs to be designed
carefully
ReferencesReferences
[1] C. Intanagonwiwat, R. Govindan, and D. Estrin, “Directed Diffusion: A Scalable and Robust Communication paradigm for Sensor Networks,” Proc. ACM MobiCom, Boston, MA, pp. 42-49, 2000.
[2]. Chris Karlof and David Wagner, “Secure Routing in Wireless Sensor Networks,” Adhoc Networks, Volume1, Issues 2-3, pp: 293-315, September 2003.