Protocols for Secure Communication in Wireless Sensor Networks

208 Chapter 6. Integrity-Preserving Communications
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Resilience of Interleaved Authentication
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Compromised nodes
Random spread, hop-to-hop
Random spread, Canvas
Random spread, Interleaved
Hitpoints, Interleaved
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Partition, Interleaved
Figure 6.24: Resilience of interleaved authentication under various attacks
off between set-up complexity and path length, multiple “virtual” paths on the
same physical path are established in the interleaved authentication scheme
that are disjoint by construction. These virtual paths are guaranteed to exist,
and they are easily constructed. In addition, only one physical path is involved
and the virtual paths are not longer than the physical path.
6.6.2 Combining Authentication Techniques
While we have considered authentication based on multiple physical and virtual
paths separately, both techniques can be combined. Each tree path itself may
use another layer of authentication, for example Canvas authentication. In that
way, the advantages of both, multi-path routing and Canvas authentication, are
combined, cf. Fig. 6.25. Table 6.6 shows that this combination gives a slight
advantage over each of the schemes alone.
6.7 Applications
A fundamental idea underlying interleaved authentication is security through
collaboration: Two (or more) independent entities provide information about
the authenticity of a message, thereby reinforcing the confidence of the receiver
that the message is indeed correctly transmitted. We give some examples where
this principle is applied.