## 2 Overview of Cyber Threats in EM
### Communication Media
#### 2.1.6 Wireless Communication Networks  
In the immediate aftermath of large-scale disasters, such as the 2006 Yogyakarta earthquake in Japan and the 2004 tsunami that hit Aceh in Indonesia, the wired telecommunication network infrastructure is often completely destroyed and is often replaced by satellite communications (Section 2.1.5), wireless mesh (WMN), mobile ad hoc (MANET) and other wireless communication networks. Comprehensive surveys of cyber threats and defence mechanisms in general-use wireless networks can be found in [78] for WMNs and in [79] for MANETs. Here, we present the information security measures taken by wireless communication networks that have been recently designed specifically for use in emergencies. The ability of wireless mesh networks (WMN) to self-heal, self-configure and provide wireless broadband connectivity at low cost makes them very attractive for public safety and crisis management communications. As a number of different emergency services need to collaborate during an operation, the requirement that is most frequently addressed in the literature is the secure access and sharing of information between multiple agencies, which may use different technologies and need to comply with different security policies. A common approach is to use cryptographic mechanisms for privacy, integrity, and authentication at the MAC layer, and IP Security (IPSec) or Transport Layer Security (TLS) at higher layers. For example, the GeoBIPS [33] self-forming broadband WMN, designed to be used by emergency reconnaissance teams and their commanding officers, serves as a relay network where privacy of voice and video communication is achieved through IPSec tunnelling. Each mobile access router is provided with a pre-shared authentication key used to sign all routing messages. [PERSON] _et al_. [36] have proposed using both encryption and blocking of devices with physical addresses that are not on a predefined list of approved ones. Privacy can also be achieved through anonymity of the entities involved in the emergency operation [80], and crisis communication may be designed based on an unusual configuration of protocols and topology, so as to obfuscate or delay a potential intruder for the duration of the emergency [81]. Self-awareness and self-adaptation have been used extensively for network resilience, for example to reduce the impact of denial of service attacks [82] and worms [83]. These concepts have only recently been explored in the context of EM networks. In the EM MANET model presented in [37], the various security components are included, excluded, activated and deactivated dynamically based on real-time monitoring performed by an intrusion detection mechanism. [PERSON] _et al._[35] have proposed a centralised access control model for MANET-based emergency rescue operations, where each group of nodes has an allocated group leader node acting as the network's gateway. The architecture presented includes authentication, authorisation and cryptographic protocol layers, with an access control policy derived based on a hierarchical public key infrastructure for the group-role and user-role relationships. In addition, every member of the group is assigned a tag, which binds with a public key, a group and specified access privileges. Whenever a member of the group wishes to transmit data, the group leader needs to first verify the tag and a password. However, as observed in [34], such protocols assume a pre-existing trust relationship between network nodes, which is not the case during major disasters where units from different emergency services need to communicate. In addition, the use of passwords or similar authentication mechanisms that require user input may be impractical in an emergency, where time is limited and human error is common. [PERSON] and [PERSON] [43] have suggested that in order to be fit for purpose, authentication in EM networks should be quick, scalable and extensible, requiring no human intervention or connection to a trusted third party.