Wireless Technologies in Process Automation - Herkules.oulu.fi - Oulu

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outsider attacks are blocked and in case of insider attack, the security gracefully degrades
(is resilient). Different types of attacks are presented in Figure 10.
Figure 10. Different types of attacks in WSN: a) interruption b) modification c)
fabrication d) interruption (Hamalainen et al., 2006).
WSN have special characteristics that enable new ways of security attacks (Hamalainen
et al., 2006). Passive attacks are carried out by eavesdropping on transmissions and may
include for example traffic analysis or disclosure of message contents (Stallings, 2005).
Active attacks consist of modification, fabrication and interruption, which in WSN cases
may include node capturing, routing attacks, or flooding (Hamalainen et al., 2006). It
should also be noted, that even though WSN themselves are resource-limited, an attacker
may have more powerful equipment available, such as laptop or PC, for making attacking
more effective (Karlof and Wagner, 2003).
When designing the security of the wireless sensor network, both low-level (key
establishment and trust control, secrecy and authentication, privacy, robustness to
communication denial of service, secure routing, resilience to node capture) and highlevel
(secure group management, intrusion detection, secure data aggregation) security
primitives should be addressed. It should also be noted, that due to resource limitations
some of the previously proposed solutions may not work due to resource limitations.
(Perrig et al., 2004)
As discussed in Section 3.3.1, WSN in industrial environments may be hybrid solutions.
This, in turn, may provide another challenge. (Roman et al., 2005) separates the security
of the wireless sensor network to two different categories. First, there is the security of
the data acquisition network, which is a collection of sensor nodes with the task of
measuring the physical data of its surroundings, and one or more base stations in charge
of collecting data from the nodes and forwarding control information from the users.
Second, there is the security of the data dissemination network which is a combination of
wired and wireless networks providing an interface of the data acquisition network to any
user.
A short review about some security technologies employed in wireless communications
can be found in (VAN, 2005). A good review about ZigBee security issues (and others) is
presented in (Baronti et al., 2007).
Throughput
Throughput defines the network’s ability to carry out the offered traffic by industrial
applications. It is impacted by the communication environment (Howitt et al., 2006).