Claudia Padovani
email: claudia.padovani@unipd.it

Elena Pavan
email: elena.pavan@unitn.it

Norms and Socio-technical Systems: Connecting Institutional and Technological Infrastructures in Governance Processes

Keywords: international norms, socio-technical systems, institutional and technological infrastructures, communication governance, analytic framework

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Introduction

There are at least three ways in which we can read the 'non-neutrality' of technology and of ICT in particular. First, from a broad social perspective, ICT inform and reform the dynamics of con-temporary societies constituting one of the primary elements for globalizing processes [START_REF] Castells | The Rise of Network Society[END_REF], [START_REF] Held | Global Transformations: Politics, Economics, and Culture[END_REF]: they transform societal interactions, respond to and solicit needs, create expectations. Hence, in a first sense, ICT are not neutral because they are mediating infrastructures that contribute to change both societal perceptions of the world and of the role of human agency in it.

Secondly, from a political perspective, ICT have progressively emerged as a policy relevant domain [START_REF] Raboy | Mapping Global Media Policy: Concepts, Frameworks, Methods[END_REF]. In the last 50 years or so, from the national to the global level, policy actors have been called to respond to challenges posed by technological transformations. Moreover, the consolidation of the ICT policy field has been accompanied by the evolution of a number of different governing arrangementsselfgovernance, public-private partnership, multi-stakeholder interventionsaimed at meeting the challenges brought by technological development to regulatory practices. Hence, in a second way, technology is not neutral because it constitutes a domain wherein different political interests and agendas are played out and because it has fostered change in (especially supra-national) governance practices.

Thirdly, at the junction of the social and the political perspectives, ICT evolution (and particularly of the Internet) and their capillary penetration into our daily lives do multiply the possibility for individuals, groups, communities to act politically and become 'part of the process.' As ICT contribute to the structuring of network societies, they also challenge traditional political processes by enabling political participation of non-conventional and non-governmental actors. This also favours the diffusion of ideas, knowledge, and cultural practices that characterize such diverse sets of actors. Hence, in a third way, ICT are not neutral because they become enabling factors for citizens' involvement, both as individuals and in their associational forms.

While social transformations brought about by ICT developments and diffusion have received increased scholarly attention, we are still in need of adequate conceptual tools and analytical frameworks to investigate the dynamics that develop when transformed policy arrangements meet the opportunity and claims for citizens' enhanced participation. This includes frameworks to investigate both the basic principles that guide the development of technological infrastructures, but also the principles those very technologies may contribute in shaping and consolidating other domains beside and beyond technology governance. Adequate frameworks should then be elaborated to study the interrelation between institutional and technological infrastructures. Institutions are to be understood here as collections of norms, including a mix of rules and practices [START_REF] Finnemore | International norm dynamic and political change[END_REF]; while technological infrastructures are seen simultaneously as instruments for global interaction, means for transforming (global) governance processes, and enabling factors for participation in political processes.

In our attempt to address this challenge, we believe a constructivist approach to world politics, provides a fruitful theoretical framework within which to position our reflections. Such an approach is grounded in the conviction that actors' interpretations of the material world depends on dynamic epistemic and normative understandings [START_REF] Onuf | World of Our Making: Rules and Rule in Social Theory and International Relations[END_REF]: the world is not a given, but rather the outcome of interactions and interpretations based on actors' experience, knowledge, and preferences. In this context, ideational forcesideas, values, knowledgebecome central and imbue communicative exchanges [START_REF] Keck | Activists Beyond Borders: Advocacy Networks in International Politics[END_REF] that sometimes consolidate into discourses, understood as "shared sets of ideas that provide frameworks that allow us to make sense of situations, embody judgments, and foster capabilities" [START_REF] Dryzek | Deliberative Democracy in Divided Societies: Alternatives to Agonism and Analgesia[END_REF].

Starting from these premises, we argue that a focus on the ideational components of policy processesand particularly norms -is crucial in studying the interrelationships between institutional and technological infrastructures. Indeed, norms emerge at the intersection between actors' discursive interaction, through which they may redefine their identities and interests. As "shared standards of behaviour for actors with a given identity," [START_REF] Finnemore | International norm dynamic and political change[END_REF] norms represent the consolidation of principled discourses into defined frameworks. Hence, agreed upon normative frameworks inform and orientate the outcome of political processes; consequently, they can be understood as one of the core 'infrastructural' elements (beside formal rules and provisions) that support governance processes and subsequent policy decisions.

Moreover, the emergence and consolidation of norms presupposes the interplay of cognitive and relational components upon which the current development and diffusion of ICT has a dramatic impact. In fact, the unprecedented levels at which ICT are embedded into every domain of human action fosters what we label socio-technical break-through: a unique situation where the social and the technical infrastructures overlap and create a hybrid social space where the circulation of ideas, principles and the construction of social relations crosses the boundary between 'the virtual' and 'the real' thus making the distinction between the online and the offline obsolete. This breakthrough poses new challenges to the study of normative developments, and invites us to expand our perspective to include in the analysis all those practicesframing, agenda setting -that inform norms' consolidation beyond the translation into official provisions, as well as the technical infrastructures that accompany and support such practices.

This paper acknowledges this centrality of norms and outline an analytical approach to the study of the relationship between institutional and technological infrastructures. Its approach aims at meeting the conceptual and methodological challenges posed by the current socio-technical context to the study of normative framework emergence and consolidation, in particular that of overcoming the separation between the online and the offline. Also, our approach translates into an analytic framework whose components can be flexibly adapted to different governance do-mains.

The paper is organized as follows. First, we outline the two core conceptual elements of our proposal: the study of norms as 'infrastructures' in world politics and the broader context in which they evolve, which we understand as a set of 'sociotechnical systems.' We conclude this first section outlining the methodological challenges to be addressed. Afterwards, we introduce and illustrate an analytical framework elaborated to meet the identified methodological and theoretical challenges. We conclude by discussing research perspectives in the application of the framework and we outline the deriving implications by referring to an ongoing research project.

2

Core Elements and Methodological Challenges

Norms as 'Infrastructures' of Governing Arrangements

Global governance can be understood as the multiplicity of networks of interdependent, but operationally autonomous actors, that produce relevant knowledge and cultural practices and/or develop frames that imbue public discourse and orientate policy agendas and/or articulate principles, norms and rules while engaging in political negotiation with a view to orientate policy-relevant outcomes [START_REF] Raboy | Mapping Global Media Policy: Concepts, Frameworks, Methods[END_REF], [START_REF] Padovani | Actors and Interactions in Global Communication Governance: The Heuristic Potential of a Network Approach[END_REF].

As a specific ideational element in the dynamics we observe, norms set standards of behaviour for actors; for instance, contributing to the definition of limits to stateactors' agency in fostering national interests and committing states and other actors to respect agreed upon principles and fundamental rights. Norms emergence and evolution on the supra-national scene are, therefore, central to governance processes, as they open up spaces for change in actors' preferences and provide reference to appropriate behaviour, sometimes contributing to "restructuring world politics" [START_REF]Restructuring World Politics. Transnational Social Movements, Networks and Norms[END_REF].

We, therefore, argue that norms should not be conceived of as 'soft' components of political processes, in comparison to the 'hard' nature of regulation and decisionmaking. Rather, norms can be considered as 'infrastructures' that enable and structure such processes. Norms contribute to the definition and transformation of actors' identities and perceptions, and to orientate their behaviour. Norms also provide cognitivenormative spaces for the formulation of new policies [START_REF] Sending | Norms, Knowledge and Constitutive Relations[END_REF]. As a consequence, their definition may become a site of struggle for actors who strategically engage in 'struggles over meaning'; thus, norms -as agreed upon standards of behaviour -can also be understood as a reflection of the (structure of) strategic interactions and power struggles that occur in political processes 1 .

Several authors remind us that norms are "difficult to see" (when do we recognize a norm when we see one?); nevertheless, they "leave an extensive trail of communication among actors that we can study" [START_REF] Finnemore | International norm dynamic and political change[END_REF]. For example, we can investigate statements and policy inputs as well as less formalized discursive practices amongst actors. In doing so, it is possible to trace their 'life-cycle' of 'emergence' in the policy context, including the following processes: 'cascade' occurs when their adoption by a wide number of relevant actors turns them into 'standards of behaviour'; and 'internalization' occurs when they become 'a given' and are perceived as natural frameworks to orientate actors' behaviour [START_REF] Finnemore | International norm dynamic and political change[END_REF], [START_REF] Florini | The evolution of international norms[END_REF].

More recent literature on norms suggests a more articulated view of such a 'lifecycle' [START_REF]Restructuring World Politics. Transnational Social Movements, Networks and Norms[END_REF], [START_REF] Sending | Norms, Knowledge and Constitutive Relations[END_REF], [START_REF] Krook | Rethinking the life cycles of international norms: The United Nations and the global promotion of gender equality[END_REF], according to which norms are always contested because, even after adoption by a broad number of actors, struggles may emerge between alternative perspectives. Furthermore, norms do not automatically imply change; rather, they provide opportunities for actors' behaviour and, as such, they are always 'works in progress' in that they are constructed and re-constructed in practice, according to actors' adoption in their actual activities and political interventions. Therefore, looking at international norms calls for a specific attention to the multi-level 'game' of interaction between norms adoption and application at the local/national and at the global levels [START_REF] Brown Thompson | Women's Rights are Human Rights[END_REF]. Finally, norms are always exposed to 'shocks': changes in the environment where norms are debated, applied, and contested can certainly interfere with their consolidation and eventually lead to further redefinition of these normative in-frastructures. This has been the case, in the context of norms pertaining to global communications and its governance, with the explosion, evolution and diffusion of information technologies in the past two decades: a situation that has originated what can now be conceived as 'socio-technical systems.'

Socio-technical Systems

It is widely acknowledged that developments in the ICT domain have been one of the driving forces of globalization processes. Hence, the network society we live in is first and foremost a society of communication networks: "patterns of contact that are created by the flow of messages among communicators through time and space" [START_REF] Monge | Theories of Communication Networks[END_REF].

The fact that ICT are now ubiquitous [START_REF] Hall | The ever evolving Web: The Power of Networks[END_REF] makes communication networks global in a twofold way: they potentially expand along telecommunication infrastructures to reach all corners of the globe; and, with the diffusion of computers and portable devices, they innervate all fields of public and private action. Together with Hall [START_REF] Hall | The ever evolving Web: The Power of Networks[END_REF], we support a vision for which changes in ICT are shaped by and, at the same time, shape society in a fluid and very dynamic way. In this sense, we believe that changes in ICT influence and, at the same time, are influenced by the structure of communication networks that innervate our society. Consistent with this perspective, we also argue that the integration of Internet communication into mobile and portable devices together with the transition to Web 2.0, are by-products of and an influencing factors in relation to the structure and the dynamics of global communication networks. Indeed, the ubiquitous presence of Internet has progressively led to a situation of seamless adaptation of social relations on the Internet infrastructure [START_REF] Giunchiglia | The Social Computer: Combining machine and human computation[END_REF]. As a consequence, the online and the offline dimensions merge together, thus, blurring the boundaries between the virtual and the real, and technology becomes the means through which we make sense of our social reality more and more [START_REF] Beer | Social network(ing) sites…revisiting the story so far: A response to Danah boyd & Nicole Ellison[END_REF].

In such a context, global communication networks resulting from the interconnection of individuals and groups and events and data are better seen in terms of sociotechnical systems that result from the intertwinement of two 'infra-structures': one given by the maze of social relations, the other by the maze of physical networks on top of which they are built [START_REF] Vespignani | Predicting the Behavior of Techno-Social Systems[END_REF]. The social space within socio-technical systems is hybrid, as it results from the merging of the online and the off-line, while social relations become cross-dimensional because they are nurtured by both mediated and unmediated interactions and are defined recursively across the two spaces [START_REF] Beer | Social network(ing) sites…revisiting the story so far: A response to Danah boyd & Nicole Ellison[END_REF].

Also, the transition from Web 1.0 to Web 2.0 technologies changes the logic through which connections within socio-technical systems are structured. From a 'culture of publicity' pursued through websites in the Web 1.0 era, we switch now to a 'culture of participation' pursued through social media tools [START_REF] Kaplan | Users of the world, unite! The challenges and opportunities of Social Media[END_REF]. The key element is the possibility for users to create and share their own information and content in real time through social media platforms, which reduces the need for specific technical knowledge for content creation, meaningfully augmenting the possibilities to enter global communication networks [START_REF] Hall | The ever evolving Web: The Power of Networks[END_REF].

The Challenge of Investigating Norms in Socio-technical Environments

According to what has been exposed, the study of norms evolution within dynamic socio-technical systems can prove to be a useful entry point to a better understanding of the interrelation between institutional and technological infrastructures (in our case in relation to the global governance of communication). If we see norms as 'institutional infrastructures' and socio-technical systems as a revised version of 'technological infrastructure,' we are left with the challenge of developing adequate analytical frameworks to study processes that take place at the junction of policy arrangements and citizens' involvement.

Norms as institutional infrastructures reflect the richness of the ideational components that enter governance processes and embody the interplay of power positions, thus, inviting due consideration of how such processes are deployed. We argue that it is often in networked interactions that governing arrangements are being shaped: ideas shared, issues framed and put on the agenda, priorities defined, alternative solutions discussed, and norms agreed upon [START_REF] Padovani | Actors and Interactions in Global Communication Governance: The Heuristic Potential of a Network Approach[END_REF], [START_REF] Pavan | Frames and Connections in the Governance of Global Communications. A Network Study of the Internet Governance Forum[END_REF]. And yet, as they operate within socio-technical systems, these networks are constantly at risk of being transformed by available technological infrastructures at least at two levels:

 Ideational/Communicative: The articulation of policy issues and decisions happens on the basis of discursive practices for which both the social interaction amongst actors and the semantics around which interactions evolve are relevant. ICT impact the creation of both social and semantic relations as they increase the relational potential of every actor (individual, organizational, governmental and nongovernmental nature) and fosters the circulation, the blending and the clash of ideas, agendas and perspectives.  Spatial: The dynamics of social and semantic construction of governance practices are recursive between the off-line (within expert committees, on the occasion of high level summits or less formal gatherings) and the on-line (through on-line consultations and mailing list exchange, but also through the structuring of thematic and issue networks in the web space). ICT embeddedness in daily social and political practices fosters the merging of the two dimensions and the hybridization of practices.

The challenge to be faced in investigating norms in their socio-technical context is to find adequate ways of dealing with the complexities deriving from actors' interactions across diverse ideational as well as spatial levels/spaces. We contend that a focus on actors' characteristics and attributessuch as the human, financial, and symbolic resources they can play out in a policy negotiationdoes not suffice in addressing the complexities deriving from multi-level interactions.

Connecting Institutional and Technological Framework

To investigate the interplay between institutional and technological infrastructures, we propose a multidimensional analytical framework based on the concept of net-works, which we consider as a suitable metaphor but also as a powerful analytic tool. The framework has been developed for the study of global communication governance but it is proposed here as a resource to investigate other policy domains. In order to address the challenges outlined above, a focus on relational dynamics involving both actors and concepts allows us to trace the 'trails of communication' that underpin the evolution of normative frameworks in governing processes. Acknowledging the "dynamics, diversity, and complexity" of such processes [START_REF] Kooiman | Governing as Governance[END_REF], different types of networks provide entry points for investigating meaningful aspects: semantic networks are useful to "map similarities amongst [actors' perceptions and] interpretations" [START_REF] Monge | Theories of Communication Networks[END_REF], while social networks help unveiling patterns of collaborative and/or conflicting interaction. Moreover, in the context of widely diffused information technologies, semantic and social networks develop across the online/offline boundary. In response to this, the explicit acknowledgement of both off-line and on-line interactions in our framework provides the means to acknowledge and investigate the hybrid feature of social space within socio-technical structures.

Table 1. Analytic framework to study networks and interactions in governance processes.

Spatial Dimension Offline Online Ideational/Communicative Dimension

Social

Offline Collaboration/ Conflicting Networks

Online Networks of Interaction

Semantic Offline Semantic Networks

Online Thematic Networks

Although each network type included in Table 1 helps us to understand a specific trend of normative framework evolution, only by analyzing and interpreting the combination and interplay of the different network structures we can reach a more comprehensive understanding of how policy domains are structured, where their boundaries are set, and what kinds of power are distributed along network ties and among actors. We have elaborated elsewhere on the heuristic potential of a network approach to communication governance [START_REF] Padovani | Actors and Interactions in Global Communication Governance: The Heuristic Potential of a Network Approach[END_REF]; here we provide a brief description of what each network allows us to look at and investigate.

Offline collaboration/conflicting networks gather social actors --whether they are individuals or organizations --operating in a certain policy domain. They can be read in terms of how relational patterns are being developed in a multi-actor environment; thus, clarifying what logics inform political interactions, such as long term solidarity and instrumental coalition-building. Indeed, ties between actors exist if a particular kind of relationship is established amongst nodes, such as cooperation, opposition, or sponsorship; and relationships can be characterized by presence, absence, and strength, such as quantifying the number of joint initiatives two organizations have realized. Furthermore, the specific positions of nodes can be evaluated in terms of their prestige, whether they involve a brokerage role, or the facilitation or control of communication flows within the network.

Offline semantic networks trace conversational patterns along which different themes are brought into the policy agenda and, in this way, provide a useful entry point from which to assess how discursive practices actually inform political processes, possibly influencing policy outcomes. They depict the collective construction of meanings and are particularly relevant when it comes to analyzing governance structures that may not aim at producing formal policy outputs, such as high-level summits as occasions for multi-stakeholder debates. Nodes are concepts and the presence of ties can be understood as a positive association among issues; while the absence of ties signals a disconnection in conversational dynamics. Also, the strength of a tie can be conceived in terms of 'semantic proximity' between different themes: the stronger the tie, the greater the association between two issues. Also, more central themes indicate priorities emerging in a field, while clusters can be read in terms of subfields catalyzing the attention of specific actors.

Online networks of interaction represent conversational dynamics deployed online that often, but not necessarily, accompany more formal governance processes. Analyzing this type of network can help uncover dynamics that may create the conditions for an enlargement or refinement of the policy agenda when physical presence is not possible. These networks can be structured by more participative settings, such as conversations involving several actors; less shared exchanges, such as conversations between only two actors; and information sharing, such as messages sent where no response is required. Nodes can be actors entering a specific discursive space, such as a forum, a mailing list; but they can also be web pages, web portals, or news services relevant to the issues being addressed. Ties can be traced to investigate actors' participation and this would allow for the identification of 'hot-spots' of online discussions. Also, ties could be traced to indicate participation in the same conversational thread, thus, contributing to the identification of 'hot-topics' in the same discussions.

Online thematic networks show how different web-based resources, such as websites, online documents, and blogs, deal with policy areas that are related to one another through hypertext links. Thus, online thematic networks may provide insights on how multi-actor conversations pushed offline by a relevant governance process are translated into web-based conversational fluxes that are accessible to all Internet users. Thematic networks can also help in mapping out the online spaces of discourse that parallel social mobilization around specific issue areas or topics. These networks can be made up of very heterogeneous nodes connected by a relation of recognition, which are not necessarily mutual; and their analysis contributes to assessing how a diversified articulation of relevant discourses may take place in the web-sphere.

Research Perspectives and Framework Application

In this paper, we have discussed the interrelationships between institutional and techno-logical infrastructures. Our discussion started from the centrality of international norms as ideational elements that are crucial for governing arrangements; and we considered the challenges posed by growingly mediatised social contexts in which norms emerge and evolve that we label 'socio-technical systems.' We then proposed a multidimensional analytical framework to investigate such complex dynamics and address the challenges posed by the consolidation of socio-technical systems. By explicitly including social and semantic as well as online and offline dimensions, the proposed approach allows us to account for the dispersion and multiplication of cognitive and relational elements that characterize the 'life-cycle' of normative frameworks within socio-technical systems. Furthermore, by looking at networked interactions, the approach moves from a predominant focus on the formal diversity of the actors involved in governance dynamics to a better understanding of how different constituencies relate to one another and how such patterns of interaction might change over time, thus, providing the grounds for norms evolution.

We are currently testing this approach by applying the framework to the case study of 'gender-oriented communication governance,' understood as that area of global communication governance that pertains to the nexus between media and gender2 . The ongoing project maps all types of networks, investigates the position of nodes, and interprets links amongst them in order to trace the evolution of normative frameworks that have over time informed governing arrangements in this domain, from the local to the global. The purpose of all of this is to reach a comprehensive understanding of how institutional and technological infrastructures interact and contribute to the transformation of power relations in the domain under investigation.

The actual conduct of the project and preliminary results seem to confirm the validity of the approach, pointing to the necessity for a joint reading of results obtained from the exploration of the different types of networks. Furthermore, it provides elements to critically reflect on the implications of translating the theoretical framework into empirical fieldwork. Certainly, research in different domains will be needed to further assess the heuristic potential of the proposed perspective.

As a consequence, norms and normative frameworks can also be investigated in relation to the different forms of power that intervene in their very elaboration and adoption: the productive power of issue framing, the institutional power of agenda setting, the coercive power of norms definition and application, as well as the network power of actors engaging in normoriented interactions. Limited space here does not allow an adequate elaboration on the challenges of adopting a multi-dimensional approach to power in world politics and global governance; we refer to the relevant literature[START_REF] Barnett | Power in International Politics[END_REF],[START_REF] Berenskoetter | Power in World Politics[END_REF],[START_REF] Castells | A network theory of power[END_REF].

Funded by the University of Padova, the project titled 'Networks and Power in Genderoriented Communication Governance,' adopts the theoretical approach and analytical framework outlined in this contribution. The case study has been chosen because it presents most of the features that characterize global governing arrangements, and because, due the long 'history' of supra-national interventions in this area, it allows to trace and compare stages of norms formation that have been characterized by different types of infrastructures, only recently coming to reflect what we have identified as 'socio-technical systems.'

drafted by Claudia Padovani; §2.2 was drafted by Elena Pavan in conjunction with the project REACtION, funded by the Provincia Autonoma di Trento (PAT) and carried on at the University of Trento, Department of Sociology and Social Research (www.reactionproject.info).


Norberto Patrignani
email: norberto.patrignani@polito.it

Iordanis Kavathatzopoulos
email: iordanis@it.uu.se

Is the Post-Turing ICT Sustainable?

Keywords: post-Turing, sustainability, material intensity, cloud computing, open hardware, smart software applications, e-waste management, stakeholders

In this paper we introduce a definition of post-Turing ICT with an initial analysis of its sustainability. At the beginning of the history of computing the attention was concentrated on the single machine: a device able to read and write a memory and able to execute different actions depending on the internal state. It was only in the 1960's that the fifth function (after input, memory, processing and output) was introduced: the network, the capability of this single computational node to be connected and exchange data with similar machines. In the last fifty years the network has grown at an incredible speed, introducing us into the post-Turing ICT era: billions of electronic devices interconnected. ICT has now a significant environmental impact along all its lifetime phases: manufacturing (based on scarce minerals), application (based on growing power consumption) and e-waste management (with open cycles difficult to close). In this paper, we introduce relevant topics to understand whether the current ICT production and consumption paradigms are sustainable, and the social consequences and implications of such a problem for stakeholders.

Introduction

When Alan Turing introduced the concept of a universal machine in 1937 in his historical article on "computable numbers," probably he never imagined the impact that such a machine would have had to our society. Indeed at those times the attention was concentrated on just one computational node: a machine able to read and write into a memory and to execute different actions depending on the symbols read and on the internal state [START_REF] Turing | On computable numbers, with an application to the Entscheidungsproblem[END_REF].

In modern world we would say that the Turing Machine was able to perform the four basic functions of a computer: input, memory, processing and output. The fifth function, the capability to communicate with other computational nodes (networking) was introduced in 1969, with the "ancestor" of Internet, ARPANET, a vision of a global network: "... a network of such computers, connected to one another by wideband communication lines" [START_REF] Licklider | Man-Computer Symbiosis[END_REF]. Open and collaborative networks will take advantage of the huge amount of machine-readable knowledge, the linked open data. The last update of the Linked Open Data Project contains more than three billions of RDF (Resource Description Format) triples (subject, predicate and object) available on the Web [START_REF]W3C: Linking Open Data, W3C SWEO Community Project[END_REF].

In this new scenario it is no more the original computational node the core of our attention, but the network effect triggered by the immense power that social networks will have when they will access the global semantic web. It will empower humanity for facing many of the social and environmental challenges ahead of us: a collective intelligence using many knowledge networks. For the first time in our history, we will be able to access tools and knowledge that will enable us to face scientific challenges and to provide services like: e-accessibility for all, socio-cultural-geographical inclusion, e-ageing.

On the other side, the post-Turing ICT poses to us new questions related to its environmental, personal and social sustainability.

Environmental and Social Issues of Post-Turing ICT

In the last forty years we have witnessed the explosion of the global network: on January 2012 we had more than 888 Million of hosts, the entries in the DNS, the Domain Name System that enable us to use symbolic names on the Internet and the Web [7]. In 2011, the Internet traffic reached more than 500 Exabytes (1018 bytes) and the forecast is that it will reach 1 Zetta-byte (1021 bytes) per year in 2015 [START_REF]Cisco: Cisco Visual Networking Index: Global Mobile Data Traffic Forecast Update[END_REF].

Even more impressive is that the number of Internet users reached 2.26 Billion on December 2011 with more than one billion concentrated in Asia [START_REF]Internetworldstats: Internet Usage Statistics, The Internet Big Picture, World Internet Users and Population Stats[END_REF]. Also, in 2011, the number of networked devices has equalled the world population (7 Billion) and it is estimated to reach more that 14 Billion in 2015 [START_REF]Cisco: Cisco Visual Networking Index: Global Mobile Data Traffic Forecast Update[END_REF].

Fig. 2. The ICT life cycle.

These billions of networked devices pose enormous questions along their life cycle: where does the material needed for their manufacturing come from? How will we produce the power needed to feed them when in use? How will the growing mountain of electronic waste (e-waste) be managed? How can we design usable and reliable ICTs? In what way should we use ICTs to sustain our interests as human beings?

Manufacturing ICT

The industrial process for producing microprocessors and chips has one of the highest "material intensities" in the industry [START_REF][END_REF] and also has an impact on the health of workers [START_REF] Patrignani | Challenging the Pursuit of Moore's Law: ICT Sustainability in the Cloud Computing Era[END_REF]. On the other side the dynamic of the so called "Moore's law" is exponential: every eighteen months the chips are more powerful [START_REF] Moore | Cramming more components onto integrated circuits[END_REF] but at the same time they consume a growing quantity of "rare earths" [START_REF] Schmitz | The Consumption Conundrum: Driving the Destruction Abroad[END_REF]. Nowadays this is starting also to have serious social and political consequences. One example is the "coltan" used for producing many of the electronic devices, from laptops to smart-phones and tablets. Its name comes from the combination of names of two minerals: Columbite and Tantalite. From them are extracted two elements: Columbium (now called Niobium, Nb) and Tantalum (Ta), fundamental for producing capacitors in the electronic industry. But these special minerals are coming from countries like Congo, where the mining activity is performed in illegal conditions for workers and have also a decisive role in the military conflicts in the area [START_REF] Vazquez-Figueroa | [END_REF]. We need to start an ethical reflection about the sustainability of pursuing this direction, probably it is time to slow-down the speed of electronic market cycles and to re-state the well-known Soesterberg principle about sustainability: "Each new generation of technical improvements in electronic products should include parallel and proportional improvements in environmental, health and safety, as well as social justice attributes" [START_REF]Soesterberg: Trans-Atlantic Network for Clean Production Meeting[END_REF].

Using ICT

Of course, when we power on ICT devices and infrastructure, we process information, and this could have also a positive contribution to the environment, for example by reducing the air pollution with tele-working and by organizing car-sharing. Probably we need to better use ICT in this direction: "Further research is needed to understand how ICTs and the Internet can contribute to reaching environmental policy goals by fostering renewable energy, reducing transport, optimising energy use and reducing material use" [START_REF]OECD (Organization for Economic Cooperation and Development): Information Technology Outlook[END_REF]. On the other side, we see that the power consumption of these machines is growing at the incredible rate of about 100% every five years [START_REF] Koomey | Estimating total power consumption by servers in the US and the world[END_REF]. The new ICT paradigm based on cloud computing is also under scrutiny, due to the computing power and storage capability concentrated in gigantic data centres located in remote locations: "under some circumstances cloud computing can consume more energy than conventional computing where each user performs all computing on their own personal computer (PC)" [START_REF] Baliga | Green Cloud Computing: Balancing Energy in Processing, Storage, and Transport[END_REF].

In conclusion, we realize that ICT requires more and more energy and many researches now estimate that its contribution to greenhouse gases (such as CO2) is close to that of airlines.

Managing e-Waste

It is estimated that, in 2020, Europe will produce more than 12 million tons of e-waste and that the mountain of this electronic waste is growing at 4% per year [START_REF]e la Ricerca Ambientale): Rapporto Rifiuti[END_REF]. Only a small percentage of these devices are recycled in some way and if we have a look at its destinations we will see many poor countries like: Haiti, Kenya, and Nigeria [START_REF][END_REF]. We now recognize also the importance of introducing new design principles like design-for-recycle and minimizing the power consumption of ICT. Also a promising sign is the new field of "open hardware", where thousands of experts exchange ideas and innovative proposals for improving hardware.

Social Issues of Post-Turing ICT

The post-Turing ICT scenario poses also new questions about social issues, as discussed in the following paragraphs.

Accessibility and digital divide. In the post-Turing ICT scenario, having the network accessibility, the economic conditions and the digital competence for being on-line is becoming more and more a "new human right": Finland, for example, has become the first country in the world to make broadband a legal right for every citizen; since July 2010 every Finnish will have the right to access to a 1Mbps broadband connection. Finland has vowed to connect everyone to a 100Mbps connection by 2015 [START_REF]BBC: Finland makes broadband a 'legal right[END_REF]. So the "digital divide" will risk excluding more seriously those who are still disconnected.

Network neutrality. The connectivity providers (mainly telecommunication companies) are questioning the business model based on "network neutrality," which is that the Internet works end-to-end and the network is acting as a "pipeline" that is "neutral" in that it does not open the data-packets. This "network neutrality" principle that is at the base of the Internet is also the great enabler of innovations: many startups and new companies were able to experiment new services because of this characteristic of the network. But the telcos are willing to introduce new business models where the network will be no more neutral, and the data-packets will not be treated at the same level. This will risk introducing a kind of first-class and second-class services based on the price you are willing to pay. This could also mine the great opportunity of the post-Turing scenario, since small and innovative companies will have to leave network bandwidth to big companies.

Knowledge as a commons. The new currency in the post-Turing era will be information (and knowledge). For this reason around knowledge is open a hot debate regarding its openness as "commons" or if it should be regarded as any other good subject to restrictions of use and distribution.

This debate is very open now but the main researches around innovation are now demonstrating that intellectual property legislations, born centuries ago, are no more fitting with the new knowledge-based society [START_REF] Lessig | Free Culture, The Nature and Future of Creativity[END_REF]. Even the 2009 Nobel Prize in Economic Sciences, Elinor Ostrom, underlined the growing importance of understanding knowledge as a shared social-ecological system [START_REF]Understanding Knowledge as a Commons: From Theory to Practice[END_REF].

The application of this framework is now moving from free and open source software, to open hardware and to scientific knowledge.

Internet censorship and control. The knowledge networks of the post-Turing era are, by definition, free and open. At the same time this new scenario, where information and knowledge are becoming strong liberation tools in many cultures, there are a growing number of governments around the world that are trying to stop this "freedom wave."

For example the 2011 Report from Reporters Without Borders, highlighted the fact that "the Internet and social networks have been conclusively established as tools for protest, campaigning and circulating information, and as vehicles for freedom" but that at the same time "repressive regimes responded with tougher measures to what they regarded as unacceptable attempts to 'destabilize' their authority" [START_REF]RSF: Enemies of the Internet[END_REF]. They can also use the information accessible on the Internet to persecute dissidents.

Indeed this new scenario is outside any previous communication schema: it is without a "single point of control" and it is based on a global collaboration between networks based on open standards. It is difficult to control, even if few new titans are emerging and collecting the vast amount of search engines traffic and data about everything, included ourselves [START_REF] Vaidhyanathan | The Googlization of Everything: And Why We Should Worry[END_REF]. Strong players have always more resources to spread certain information in sophisticated ways in order to manipulate people they target.

Remote working. The impact of computers into the workplace have been investigated since the 1960's but now, for understanding what does it mean to work in global knowledge networks, we need a leap into a new scenario. In particular for knowledge workers, working in a "virtual workplace for a virtual enterprise" is becoming a daily experience.

The XXI century's enterprise is (symmetrically) becoming, a "workplace without workers." We have more and more knowledge workers hired "on demand" by global job brokers: brains stay in their (poor) countries, but minds cross the oceans. As a consequence, the "social" context of the traditional workers is completely disappearing. Now we have global job broker agencies like: teamlease.com from India that is providing well-educated workers all over the world; odesk.com that provides all kind of contractors; getacoder.com that helps in finding freelance programmers; and, elance.com that "helps businesses hire and manage in the cloud." Young programmers hired on-demand and with a good knowledge of English can make up to $300 per month [START_REF] Kock | Encyclopedia of E-collaboration[END_REF], [START_REF] Codrington | Freelancers, eLancers and Cloud workers[END_REF]. These deep social issues in this post-Turing era restate very old questions: are we going towards a utopian participation of (knowledge) workers in the new enterprises or are we going towards a dystopian new kind of cyber-slavery?

Privacy. Probably privacy is the oldest social and ethical issue related to computing. What is new in our global knowledge networks scenario? From one side the inclusion of our physical body into the network via RFID tags is turning our bodies into nodes at the edge of the network. From the other side we have the gigantic amount of collected data (so called Big Data) that will enable very few powerful organizations to analyse and extract new information through special data mining technologies.

They will be able also to find "non-obvious relationships" (also known as the "mosaic" effect) by collecting information about us from different sources. A good example of this advanced use of data mining and Big Data is the "Narwhal Project," a project that could change the results of the 2012 U.S. President elections [START_REF] Issenberg | Obama's White Whale. How the campaign's top-secret project Narwhal could change this race, and many to come[END_REF].

Cloud computing. The vast amount of computing and storage resources available in big data centres, convinced large corporations to start making them available to customers. They can provide on-demand and in a flexible way: software as a service (SaaS), where users can just use sophisticated software applications by paying a fee for each user; platform as a service (PaaS), where users can have access to large processing power and development environments for testing their applications; and infrastructure as a service (IaaS), where users can buy storage and processing capability readily available in the cloud provider's data centre.

This big shift in computing paradigms will enable decision makers to move ICT from capex (capital expenditure, money spent to acquire physical assets, machinery) to opex (operating expense, ongoing cost for running a system). At the same time, this development is opening a long list of issues: strong authentication will become a requirement, using a resource will be completely separated from ownership, cloud brokers will be new intermediaries that complicate the picture, we will have a kind of de-perimeterization (disappearing of boundaries between systems and organizations), it will be possible to clone data at a negligible cost, cloud traceability will be necessary in case of disasters, the risk of monopoly and lock-in will increase, and the actual data location must be disclosed for some legal compliance requirements.

Also, information could be downloaded not (necessarily) only by the up-loader, creating an issue of intellectual property: sensitive personal and corporate information risk to be out of the control of the owners.

Internet governance. The global infrastructure is open and without a center, nevertheless there are few "core" systems that have become very critical for the entire infrastructure, such as the Domain Name System.

The very critical collection of systems and applications that allow the use of symbolic names over the Internet and the Web has to be unique by definition. This uniqueness introduces one of the few "central" resources of the network: the need for an authority that will release unique names and will take care of the management of this gigantic "table."

This authority is now the famous ICANN (Internet Corporation for Assigned Names and Numbers), based in the U.S. This authority is one of the many controversies that have been discussed for several years in the Internet Governance Forum, the last of which was in Nairobi in 2011.

In these yearly forums, several global issues related to the global Internet governance are addressed: security, accessibility, critical infrastructures, and many others. The post-Turing ICT scenario poses huge questions to international bodies like the UN and the ITU (International Telecommunication Union) but it is difficult to find global agreements related to a commons like the Internet.

Information overload. Once we are globally interconnected and "always on," we recognize also that our minds have a limited bandwidth and have limits in "absorbing" messages. We need time for thinking and questioning, we cannot simply stay always online and receiving millions of inputs. Somewhere we need to stop those inputs and have a little of silence. We need this for avoiding "information overload" and also for building our autonomy, our interpreting codes, and our histories. Otherwise the risk is that we will be totally manipulated. Slowing down the pace of incoming messages will become a strategic resource in a post-Turing scenario.

A new world. A post-Turing scenario implies the creation of a new social world. Its novelty and its difference are of course important aspects but the way it comes to the fore is also significant because it is out of our control. The state of interconnections, communications and collaborations emerges by itself and by chance depending on previous or prevalent conditions at a certain time and place. What is there has not been explicitly designed for any particular reason by anybody. Thus the questions are: Is it sustainable in itself? And where does it lead us?

Concluding Discussion

Taking into the account the issues above, what are the implications for society? What are the key aspects we need to change in our paradigms? How could we do that?

The post-Turing scenario will introduce humanity into an interconnected world with global knowledge networks, with the promising "collective intelligence" opportunity. But at the same time, this poses to humanity a collection of sustainability issues on the environmental, personal, biological and social sides.

On the environmental side we will need to slow down the consumption of natural resources for building electronic devices and improve the re-use and re-cycling of hardware. We need to start thinking ourselves as (responsible) "digital citizens" and not just "digital consumers." We need to question the market pressure of consuming new electronic gadgets at a growing speed. Also, in order to have really recyclable hardware, we need to introduce recyclable-by-design devices. This can be optimised by leveraging the collective intelligence enabled by a post-Turing scenario. So we need to introduce an "open hardware" approach [START_REF]Arduino[END_REF], where all specifications and documentation are available to experts.

Smart software applications could be also useful in supporting us in decreasing our environmental impact, reaching our main goals and satisfying our significant values.

In the "remote working" area we need to start a new way of thinking that questions the exploitation of knowledge workers: they are the best candidates to become independent workers instead of "employees" of some intermediate obscure job brokers. On the social side of post-Turing ICT the long list of issues in front of us will require a new interdisciplinary approach that will enable the collaboration of many disciplines like: computing and networking, sociology, psychology, anthropology, and philosophy. It is the first time in our history that we have this opportunity at global scale; let us stay humans.

Fig. 1 .

 1 Fig. 1. Post-Turing ICT.


Renier Van Heerden

Heloise Pieterse
email: hpieterse@csir.co.za

Barry Irwin
email: b.irwin@ru.ac.za

Mapping the Most Significant Computer Hacking Events to a Temporal Computer Attack Model

Keywords: computer attack model, ontology, network attack prediction

des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Introduction

Computer hacking (also referred as computer cracking) developed in conjunction with the normal usage of computer systems. This paper discusses some of the most significant hacking events and the features that made them unique. The events listed are considered to be significant because of their unique impact, methodology or other properties. The level of significance is an abstract and relative measure. Other attempts to judge the importance of hacking events have been made by Heater [START_REF] Heater | Male: A Brief Timeline[END_REF], Hall [START_REF] Hall | The 7 worstcyberattacks in history (that we know about)[END_REF] and Julian [START_REF]Julian: 10 Most Costly Cyber Attacks in History[END_REF].

Research in computer network attack prediction at the Counsel for Scientific and Industrial Research (CSIR) in South Africa has resulted in the development of a Taxonomy and Ontology of computer network attacks. A temporal attack model was developed with the goal of separating the different stages of a computer network attack. The model consists of the following basic stages: Target Identification; Reconnaissance; Attack; and Post Attack. The Attack stage has the following sub-stages: Ramp-up; Damage; and Residue. Research was also organized into strategies for identifying the Reconnaissance and Ramp-up stages. The attack model is a valuable asset in the protection of critical infrastructure as it has the ability to identify attacks at an earlier stage and so improve the responsiveness to incidents. This paper presents the authors' view on the most important hacking events, and cannot in itself be considered absolute. We chose events based on either the uniqueness of the technique used or their unique impact. The attack model is presented in more detail in Section 2. Section 3 describes the most significant hacking events and their characteristics. Section 4 identifies trends in hacking development. Section 5 maps the hacking events to our temporal attack model. Section 6 focuses on the protection of critical infrastructure. Section 7 discusses mayor future hacking events.

2

Attack Model

Computer Attack Taxonomy and Ontology

A detailed taxonomy that describes computer based attacks has the following classes [START_REF] Van Heerden | Classifying Network Attack Scenarios using an Ontology[END_REF]: actor; actor location; aggressor; attack goal; attack mechanism; automation level; effects; motivation; phase; scope; target; and vulnerability. The taxonomy was then used to describe the following scenarios [START_REF] Van Heerden | Classifying Network Attack Scenarios using an Ontology[END_REF]: denial of service (DoS); industrial espionage; web deface; spear phishing; password harvesting; snooping for secrets; financial theft; amassing computer resources; industrial sabotage; and cyber warfare.

Temporal Attack Model

The Phase class in Section 2.1 was used to build the Temporal Attack Model. The Target Identification stage represents actions undertaken by an attacker in choosing his/her target. Identification of these actions falls outside the scope of the network attack prediction project, but forms part of the overall attack model. The Reconnaissance stage represents actions undertaken by an attacker to identify potential weak spots. These actions are the earliest indicators of an impending network attack, and occur before any real damage has occurred. Popular reconnaissance actions include network mapping and scanning with tools such as Nmap and Nessus. Google and other search engines can also be used to identify potential weak spots. The Attack stage represents modification of the target system by an attacker. The system can be modified in the following aspects: Confidentiality; Integrity; and Availability. These aspects are also known as the CIA principles. Confidentiality refers to prevention of disclosure of information to unauthorized individuals or systems. Integrity means that data in a system cannot be modified undetectably. Availability refers to the availability of information when required by the system to serve its purpose. In computing, e-Business and information security, it is necessary to ensure that data, transactions, communications and documents are genuine. It is also important that authentication validates the identities of both parties involved.

In figure 1 the Temporal Attack Model is represented. The Attack stage is subdivided into sub-stages. The first sub-stage is the Ramp-up stage. This sub-stage refers to the preparatory actions performed by an attacker before his/her final goal can be attained. The targeted computer network is modified in this stage, but only in preparation for some other goal. This stage typically includes the installation of backdoors and other malware. The Damage sub-stage refers to actions undertaken by an attacker during the achievement of his/her final goal. In this sub-stage the network is damaged according to the Information Security CIA principles. For example when an attacker launches a Distributed Denial of Service (DDoS) attack on a network, the Damage sub-stage is entered as soon as the attack is launched. The action of installing DDoS attack software falls under the Ramp-up stage.

The Residue sub-stage refers to unintended communications and actions by malware after an attack has been completed. For example, computers that have incorrect time settings may attack their target at a later date and/or time than when the original coordinated attack was planned. This is also noticed in DDoS attacks.

The Post-Attack Reconnaissance stage refers to scouting and other similar reconnaissance actions performed by an attacker after completion of the Attack stage. The attacker's goal in this stage is to verify the effects of his/her attack and to assess whether the same methodology can be used again in the future.

Significant Hacking Events

We consider the following to be the most significant hacking events.

Brain Virus: The world's first computer virus was created by two brothers, Basit and AmjadFarooqAlvi, in Lahore, Pakistan [START_REF] Desai | Towards an undetectable computer virus, Master's thesis[END_REF]. This was a boot sector virus since it only affected boot records [START_REF] Subramanya | Computer viruses[END_REF]. The Brain virus marked the area where the virus code was hidden as having bad sectors [7]. It occupied a part of the computer memory and infected any floppy disk that was accessed. It hid itself from detection by hooking into the INT13. When an attempt was made to read the infected sector, the virus simply showed the original sector. This resulted in a change to the volume label.

Morris Worm: On 2 nd November 1988 a Cornell graduate student, Robert Tappan Morris, unleashed the first computer worm [START_REF] Orman | The Morris worm: a fifteen-year perspective[END_REF]. It started as a benign experiment with a simple bug in a program, but the worm replicated much faster than anticipated [START_REF] Chen | Worm epidemics in high-speed networks[END_REF]. By the following morning it had infected over 6000 hosts [START_REF] Cass | Anatomy of malice [computer viruses[END_REF]. The worm could not determine whether a host had already been infected or not and as a result distributed multiple copies of itself on a single host. The exponential increase in data load eventually tipped off the system administrators and the worm was discovered.

CIH Virus: The CIH virus, also referred to as the Chernobyl or E95.CIH virus, first appeared in June 1998 [7]. It was created by a Taiwanese college student called Chen Ing-Hau [START_REF] Bosworth | Computer security handbook[END_REF]. It possessed a destructive payload with the purpose to destroy data. On release, the virus attempted to override a portion of the hard disk as well as the flash ROM of the PC. It infected over a million computers in Korea at the time [7].

I-LOVE-YOU Worm:

The I-LOVE-YOU worm first appeared on May 4, 2000 in the form of an e-mail with the subject: I-LOVE-YOU [7]. It was created by a student named Onel de Guzman, and originated from Manila, Philippines. The worm code was written using Visual Basic and processed by the WScript engine [START_REF] Bishop | Analysis of the ILOVEYOU Worm[END_REF]. It targeted computers using Internet Explorer and Microsoft's Outlook. Within a few hours it had spread worldwide via e-mail by making use of Outlook addresses of infected users. It exploited human curiosity, enticing people into opening an untrusted email.

Code Red Worm: The Code Red worm appeared on July 12, 2001. It exploited a buffer-overflow vulnerability in Microsoft's IIS web servers [START_REF] Moore | Code-Red: a case study on the spread and victims of an Internet worm[END_REF]. Upon infection of a machine, it checked whether the date was between the first and the nineteenth of the month. If so, a random list of IP addresses was generated and each machine on the list was probed to infect as many other machines as possible. Proper propagation of the worm failed due to a code error in the random number generator [START_REF] Zou | Code red worm propagation modeling and analysis[END_REF]. On 19 July a second version of the Code Red worm appeared that infected computers at a rate of 200 hosts per minute [START_REF] Chen | Worm epidemics in high-speed networks[END_REF].

Estonia Hack Attack: Early in 2007, a series of politically motivated cyber-attacks struck Estonia [START_REF] Czosseck | Estonia after the 2007 Cyber Attacks: Legal, Strategic and Organisational Changes in Cyber Security[END_REF]. The attacks included web defacements and DDoS attacks on Estonia government agencies, banks and Internet Service Providers. The attacks followed the removal of a bronze statue in Tallinn, which commemorated the dead from the Second World War [START_REF] Davis | Hackers Take Down the Most Wired Country in Europe[END_REF]. At the time of the attacks, Estonia was one of the leading nations in Europe with regards to information and communication technologies [START_REF] Czosseck | Estonia after the 2007 Cyber Attacks: Legal, Strategic and Organisational Changes in Cyber Security[END_REF]. This can be considered an example of cyber warfare and its potential effects.

Conficker Worm: The Conficker was the first worm to penetrate cloud technology [START_REF] Sarwar | Dawn Of The Mobile Malware: Reviewing Mobile Worms[END_REF], [START_REF] Sharma | An Analytical Survey of Recent Worm Attacks[END_REF]. It first appeared in November 2008 and quickly became one of the most infamous worms to date. The Conficker worm controlled over 6.4 million computer systems and also owned the world's largest cloud network at the time. As a result of the infrastructure of a cloud, the worm could propagate much faster, infect a broader range of hosts and cause greater damage. Conficker has not been used as an attack weapon since, and it is speculated that it might have been a precursor to Stuxnet.

Stuxnet Worm: Stuxnet was one of the most complex threats ever analysed [START_REF] Falliere | W32.stuxnet dossier: version 1.4[END_REF]. The primary purpose of Stuxnet was to target industrial control systems such as gas pipelines and power plants with the goal of reprogramming the programmable logic controls (PLCs) of the systems to enable an attacker to control them. Stuxnet was also the first to exploit four zero-day vulnerabilities as well as compromise two digital certificates. As of September 29, 2010, Iran had the greatest number of infected computer systems. Stuxnet has shown that direct-attack attempts on critical infrastructures are no longer a myth but a definite possibility. Stuxnet actions can be considered an act of war, but no one has officially claimed responsibility for it.

Trends

Although our selection of significant hacking events is subjective and does not represent a comprehensive list, some interesting trends can be identified. Firstly, the monetary impact of each event is shown in figure 2. The vertical scale represents an estimation of the effect. Effects are classified as follows: 5severe financial impact; 4significant financial impact; 3major financial impact; 2minor financial impact; and 1negligible financial impact. On the horizontal scale, the attacks are listed in chronological order. Figure 3 lists the most common countries of origin of hacking events. Most events surprisingly originate from the Philippines. Figure 4 illustrates the number of events per continent, with Europe and Asia at the top of the list. In most hacking events, small malware of between 1,000 and 100,000 bytes were utilized. The significant exception is Stuxnet, with a size of over 1.5 megabytes. The progressive increase in bandwidth and computer memory size will likely lend itself to the use of bigger malware (figure 5). The protection of critical infrastructure involves the readiness to act against serious incidents threatening the critical infrastructure of a nation. Recently there is an increasing need to protect critical infrastructure from terrorist or other physical attacks, including cyber-attacks [START_REF] Bradley | Critical infrastructure protection[END_REF]. The previous sections emphasized this need by reviewing eight of the most significant computer network attacks. Apart from Stuxnet, there have been other instances of infrastructure attacks through computer networks [START_REF] Tsang | Cyberthreats, Vulnerabilities and Attacks on SCADA Networks[END_REF]: ─ Maroochy Shire Council's sewage control system in Queensland, Australia was attacked. ─ A teenager in Worcester, Massachusetts broke into the Bell Atlantic computer system and disabled part of the public switched telephone network using a dial-up modem connected to the system. This attack disabled phone services at the control tower, airport security, the airport fire department, the weather service, and carriers that use the airport.

Conclusion and Future Work

The goal of the network attack model was to represent the majority of network based attacks. This temporal model was verified by mapping eight significant computer network attacks. The attacks were chosen to represent the most significant computer attacks (hacks) in the authors view. The mapping of these attacks shows the usability of the temporal model in aiding critical infrastructure protection.

To prevent or protect against computer attacks, the CSIR are investigating methods to detect the Reconnaissance and Ramp-up stages of an attack. If these stages can be detected, mitigating action can be taken against computer attacks. The attack model is under development and will evolve as the research progress. Future work includes adding new dimensions to the classification of attacks, namely origin and motivation of the attack. Reviewing the reasons of why a network was easily penetrated and focusing on the commonalities of learnt lessons will also be explored.

Fig. 1 .

 1 Fig. 1. Temporal Network Attack Model.

Fig. 2 .

 2 Fig. 2. Monetary impact of hacking events.

Fig. 3 .

 3 Fig. 3. Countries of origin of hacking events.

Fig. 4 .

 4 Fig. 4. Hacking events per continent.

Fig. 5 .

 5 Fig. 5. Infection size in bytes.

─

  In 2000, the Interior Ministry of Russia reported that hackers seized temporary control of the system regulating gas flows in natural gas pipelines. ─ In August 2005, Zotob worm crashed thirteen of DaimlerChrysler's U.S. automobile manufacturing plants forcing them to remain offline for almost an hour. Plants in Illinois, Indiana, Wisconsin, Ohio, Delaware, and Michigan were also forced down. ─ The Sobig virus was blamed for shutting down train signaling systems throughout the east coast of the U.S. The virus infected the computer system at CSX Corp.'s Jacksonville, Florida headquarters, shutting down signaling, dispatching, and other systems. ─ The Nuclear Regulatory Commission confirmed that in January 2003, the Microsoft SQL Server worm known as the Slammer worm infected a private computer network at the idled Davis-Besse nuclear power plant in Oak Harbor, Ohio, disabling a safety monitoring system for nearly five hours. The Attack Model of Section 2.2 is able to map these Infrastructure computer based attacks. The ultimate goal of this research is to prevent such attacks by identifying the initial stages early enough for preventative actions. The model is able to present any type of computer network based attack, since computer based attacks on Infrastructure uses the same techniques and methodologies as traditional computer network attacks. The Reconnaissance and Ramp-up stages for attacking Infrastructure are similar for attacking computer networks.

Attack Model Map

The following sections describe how the most significant hacking events map to the Attack Model in Section 3.

Brain Virus

─ Target Identification: Experimentation with 5.25 inch floppy disks. ─ Reconnaissance: Exploring and experimenting with the DOS File Allocation Table (FAT) file system on the floppy disks. ─ Ramp-up: Writing and inclusion of malicious code on a 5.25 inch floppy disk. ─ Damage: Changing the volume label to read either Brain or ashar. ─ Residue: The changed disk label and the message left in infected boot sectors. ─ Post attack: Using the same technique to infect hard disks.

Morris Worm

─ Target Identification: Experimenting with the ARPANET. ─ Reconnaissance: Scanning the ARPANET network for flaws and vulnerabilities. ─ Ramp-up: Writing the experimental program which includes the source code for the worm. ─ Damage: The release of the experimental program on the ARPANET. ─ Residue: A machine being infected multiple times rather than only once. ─ Post attack: Experimenting with the possibility of a worm in different environments.

Code Red Worm

─ Target Identification: Exploring the Microsoft IIS server configurations. ─ Reconnaissance: Using well-known search engines to search for potential vulnerabilities in the IIS server software. ─ Ramp-up: Writing the Code Red worm code and identifying a buffer overflow vulnerability in the software. ─ Damage: Launching a DoS attack against randomly selected server IP addresses. ─ Residue: The worm used a static seed as its random number generator and so generated identical lists of IP addresses that caused computers to be infected multiple times. ─ Post attack: Searching for additional weaknesses in Microsoft's IIS servers.

Estonia Hack Attack

─ Target Identification: The relocation of the Bronze Soldier in Tallinn. ─ Reconnaissance: Using well-known search engines to identify possible weaknesses in the websites of well-known Estonian organizations. ─ Ramp-up: Installation of malware on targeted computer systems. ─ Damage: Government and commercial services (such as banks) became unavailable during the attack.

─ Residue: Russian-language bulletin boards and one defaced website with the phrase: "Hacked from Russian hackers". ─ Post attack: Scanning of the infected computer networks to determine the effects of the attacks.

Conficker Worm

─ Target Identification: Exploring cloud computing. ─ Reconnaissance: Using well-known search engines to identify possible vulnerabilities in a cloud computing system. ─ Ramp-up: Writing the code for the Conficker worm. ─ Damage: Launching Conficker worm in the cloud, thus making its target resources available to the attacker. ─ Residue: No unintended attacks caused by the worm in this case. ─ Post attack: Releasing additional versions of the worm to verify the effects.

Stuxnet Worm

─ Target Identification: Uranium enrichment infrastructure in Iran. ─ Reconnaissance: Using well-known search engines to identify possible vulnerabilities in industrial software and equipment developed by Siemens. ─ Ramp-up: Writing the code for the Stuxnet worm and installing additional malware on targeted computer networks. ─ Damage: It physically damaged the Iranian Nuclear enrichment systems. ─ Residue: Infiltration of computer systems other than those in Iran. ─ Post attack: Verifying the effects on Iran's industrial software systems.