Download Scenario driven security analysis and architecture driven

UbiSec&Sens
Deliverable D<0.2>
We sum up the major attacks which we have tackled in our vineyard application in Table 4. Referring to
these security threats, a secure agriculture WSN application for vineyard monitoring shall be equipped with the
following modules:
1. Persistent and replicated storage of monitored data at various nodes
The tinyPEDS module provides persistent and replicated data storage. The readings collected from a
group of motes in a region are backed up on another geographical region. This guarantees the availability
of the measurements whenever an attack results in a partial handicap of the network.
2. Plausibility check of monitored data
RANBAR is a plausibility check that runs on the aggregator nodes in order to discard poisoned readings inserted by an intruder. This module is desirable when the integrity of the data is important. It
is based on statistical model that can probabilistically filter out malicious values after receiving several
measurements.
3. WSN access control supporting relaxed mobility
When a farmer needs to retrieve the data from the network, a reactive protocol is needed in order to route
the query towards the destination. For this reason we use the Lightweight UNderlay Adhoc Routing
(LUNAR) adapted for ad-hoc and wireless sensor networks called tinyLUNAR. The tinyLUNAR is a reactive end-to-end connection oriented routing protocol that uses a label switching forwarding technology.
It offers a native support for data-centric and address-centric communications.
4. Reliability
The reading values of the light and the moisture vary slowly in time as well as geographically. These
climatic and bio-chemical facts yield a sort of a natural replication of the measurements resulting into a
remedy against loosing measurement packets before storage. While reliability before storage is elective,
it is mandatory for querying data from the network. Once the need of retrieving the data rises up, the
querying mechanism needs to be reliable. This reliability is ensured by the nanoTCP transport protocol,
an end-to-end connection oriented protocol using acknowledgements and retransmissions.
5. Energy efficiency and aggregation
In order to extend the network life time, we decrease the number of messages communicated. Our chosen
way is to adopt clustered network architecture. Sensors of each cluster collect readings periodically
and send them to an elected aggregator who aggregates the readings and sends a single message with
the computed measurement values to be backed-up. Being an aggregator node means higher energy
consumption. Therefore a ”fair” load balancing scheme is needed which efficiently distributes the load
between the nodes. We use PANEL for the periodical aggregator election based on a moving reference
point. The closest node to the reference point in a cluster is chosen as the aggregator of the cluster.
1.2
1.2.1
Vehicular
Sensor data type
For the Vehicular WSN we plan to use sensors that measure the temperature on the road as well as detect a
moving obstacle on the road (see Figure 2).
1.2.2
Amount of Sensors
The amount of sensors per critical region on the road should not be more than 10 sensor nodes plus one sink
node.
1.2.3
Sampling Rate
Continuously at the sensor nodes, temporary at the sink node.
Page 15 of (61)
c
UbiSec&Sens
consortium 2007