GISdevelopment.net --> Proceedings --> GISDECO --> 2004
Abstract
Infrastructures – both technical and social - are considered to play a key role in facilitating the resumption and acceleration of growth in developing countries. Well performing infrastructure services are crucial for enabling countries to participate in and benefit from global developments. A (geo)spatial data infrastructure (SDI) can be considered a domain specific infrastructure. As such it carries the characteristics of other infrastructures, with peculiarities of the (geo)spatial data domain. This paper examines and defines what sort of infrastructure SDI, and what the implications of this view are for its management. It is argued that in analogy with other infrastructures success depends not only on operational performance but also on the demand for the service: if effective demand is lacking or other services are desired, use or consumption will be less than expected. Effective demand is however dependent on reliability. For users, reliability means that a service has a high probability of being available in the quantity, quality, and at the time required. Substantial changes in reliability will induce changes in users’ behaviour. Users demand different levels of reliability depending on their particular usage activity, and adopt reliability-enhancing strategies when the levels provided do not meet their needs. The reliability, capacity, and cost of infrastructure services at any point depend on the management and maintenance practices of infrastructure suppliers and the dynamic response of all users to infrastructure unreliability.
Managing SDI’s involves therefore assessing the extent to which users adopt such reliability-enhancing strategies. These strategies can in particular be found when comparing business and revenue models of commercial users of spatial information with public providers of spatial information. It is argued that incorporation of real time spatial data use, forceful and diverse business models and interrelated services provision are examples of reliability-enhancing strategies adopted by private users. SDI providers and contributors would need to respond to these strategies. Such a response would need to include management of 1) Maintenance & condition of technical infrastructure; 2) Demand & supply performance; 3) Competitive markets & financial performance; 4) Degree of government intervention; 5) Operational performance. The paper concludes by reviewing what this management would entail from these various perspectives, what would be the implications for those developing countries who are only just starting with SDI development, and which performance indicators would need to be measured to support SDI management.
Introduction
Infrastructures – both technical and social - are considered to play a key role in facilitating the resumption and acceleration of growth in developing countries. Well performing infrastructure services are crucial for enabling countries to participate in and benefit from such developments as the globalisation of trade. A (geo)spatial data infrastructure (SDI) can be considered a domain specific infrastructure. As such it carries the characteristics of other infrastructures, with peculiarities of the (geo)spatial data domain. This paper examines and defines what sort of infrastructure SDI is, and what the implications of this view are for its management. The emphasis will be on the reliability of infrastructure services, and how that has an impact on supply and demand.
Infrastructures and reliability
In analogy with other infrastructures success depends not only on operational performance, but can be evaluated and classified from several perspectives, such as in (Israel, 1992):
One key element in any of these perspectives for enhancing efficiency and effectiveness of infrastructure is through an increased focus on reliability of services. Where the first aim of any (information) infrastructure is to enhance access to (information) services, one would find that access alone is not enough. If effective demand is lacking or other services are desired, consumption will be less than expected. For users and beneficiaries, reliability means that a service has a high probability of being available at an affordable cost, and in the quantity, quality, and at the time required. This concept of reliability directly links provision of infrastructure to a specific use, and providers to users. Substantial changes in reliability will induce changes in users’ behaviour, and thus suppliers face however a variety in demands for reliability. Users demand different levels of reliability depending on their particular usage activity, and adopt reliability-enhancing strategies when the levels provided do not meet their needs. The reliability, capacity, and cost of infrastructure services at any point depend on the management and maintenance practices of infrastructure suppliers and the dynamic response of all users to infrastructure unreliability.(Israel, 1992) describes:
Industries producing goods for trade depend on infrastructure as an input. The reliability, capacity, and cost of infrastructure services at any point depend on the management and maintenance practices of infrastructure suppliers and the dynamic response of all users to infrastructure unreliability. Users demand different levels of reliability depending on their particular usage activity, and adopt reliability-enhancing strategies when the levels provided do not meet their needs. The extent to which users adopt such strategies can be used as information to infrastructure providers when selecting optimal investment decisions to improve either the reliability or capacity of infrastructure systems.
For the case of Nigeria (Adenikinju, 2003) notes that poor electricity supply has proved to be the major infrastructure constraint confronting the business sector in Nigeria today. Electricity supply is both unstable and of very low quality. Black out and brown outs are common features of electricity supply in Nigeria. In fact, the average Nigerian firm experiences power failure or voltage fluctuations about 7 times per week, each lasting for about 2 h, without the benefit of a prior warning. This has contributed to the low productivity and low competitiveness of the Nigerian manufacturing sector.
Impact on SDI’s
Applying the above perspectives to SDIs, one could find that:
In more detail, one could describe these by a number of quality parameters, such as in Table 1 and Table 2:
From a transaction cost theory point of view, enhancing reliability by users is seen as a transaction cost, whereas enhancing reliability by providers is seen as an increase of maintenance cost. The optimum is at the point where the sum of the two is at its minimum, as can be seen in Fig. 1.
Figure: Cost of reliability of GDI
More and more, we are moving to a society in which the management of information––through communications and computer networks––is becoming the key strategic resource that determines the competitiveness of nations and communities. Despite massive investments in information infrastructure, many believe that the full promise of the technological revolution remains unfulfilled––both in the realm of economic development, and in terms of social progress.
And concludes that the key policy challenges of the knowledge-based economy include:
An environment that is however largely unreliable will not generate any economic activity, as unreliable supply will influence manufacturers’ decisions in respect of choice of business, location and input combination. Wherever possible, business activities that are highly (geo-)information intensive are avoided. The short-term response of private firms is than the intensive use of non-(geo-)information inputs.
Bringing this further to the cost and cost efficiency questions, one could argue that the cost of infrastructures would than also include the cost of the reliability-enhancing and/or the cost of avoiding reliability-dependency strategies. This dependency between systems is highlighted by (Hunker, 2002), who notes that:
Global or continental critical infrastructures –– including electric power, telecommunications, and the Internet –– are now the control plane for advanced economies. The occasional failures of these key infrastructures illustrate not only our dependence, but also the unanticipated interdependencies between systems. For example, the 1998 failure of a single telecommunications satellite, Galaxy 4, led to an outage of nearly 90% of all pagers in the United States, while also causing a number of unanticipated failures: many banking and financial services (credit card purchases, automated teller machines) were interrupted, as was communications with doctors and emergency workers.
It relates the cost of providers to that of users if certain strategies from either side are implemented. It also shows that it is not enough to look only at the (static) user needs, but that one needs to take into account the users’ (dynamic) behaviour, or dynamic reaction to certain static or dynamic situations. In absolute terms one could summarize this as in Table 3.
Yet, refinement could be in the question whether cost is (too) high or low. These absolute terms assume only one item of spending, whereas in practice users would always address the question in relation to other spending items. It would thus be better to include a sense of relativity, for example through the issue of “affordability”. Affordable in this context would mean both possible and acceptable (although one could also make a more refined distinction, where one would include the option “acceptable” and “not acceptable”). Users can afford cost if it doesn’t exceed a certain percentage of their overall spending, or if somehow the cost may lead to a certain benefit. How affordability leads to certain users’ behaviour is described by (Cave and Vogelsang, 2003). They suggests that the strategies of potential new entrants to mobile telecom facilities strategies will be influenced by the level of access prices and on the degree of investment in infrastructure which entrants have to make to be eligible to purchase interconnection services at wholesale prices.
Providers, either government of non-government funded, will define affordable in terms of budget or budget constraints, or cost recovery potential. If a certain requirement implies considerable cost, exceeding the budget or cost recovery potential, providers may be forced to deny any investment to comply with such requirement. The issue of “affordability” also incorporates the dynamics of a situation. What may be affordable now, may not necessarily be affordable in the future (Table 4 and Table 5).
Management response
Following the emphasis on reliability, managing SDI’s involves assessing the extent to which users adopt such reliability-enhancing strategies. Some of these strategies can be found when comparing business and revenue models of commercial users of spatial information with public providers of spatial information. A number of commercial spatial services providers have incorporated real time spatial data use, forceful and diverse business models and interrelated services provision. examples of reliability-enhancing strategies adopted by private users.
In theory the management response could be visualised by the following change in operations and activities:
Figure 2. Shift in reliability perspective
Globally the public sector is under increasing stress to reduce their budgets and scale down their activities, which could be outsourced and privatized. Part of these activities includes infrastructural works. One of the major reasons why many infrastructures in developing countries are not functioning from an public sector point of view is because they have lost value due to the lack of maintenance. The same would be true for systematic data collections and a SDI. SDI being in the realm of public interests, this maintenance is often expected from the public sector. Yet, even in countries where data are being upgraded, for example through donor incentives or systematic Land Information Systems projects (example Nepal), often one sees a systematic bias in favor of new construction and design at the expense of maintenance of available records. Most of the value of the SDI is derived from its capability of maintenance. Part of the problem is the failure to include beneficiaries in the (information) system design, top-down or donor driven approaches that emphasize complex ICT solutions. Problem is obviously a focus on short-term technical rationality rather than long-term process of institutional development. In that sense, developments in SDIs follow a similar pattern as most other development projects.
(Adenikinju, 2003) for the Nigerian case describes that there are essentially five ways by which firms may respond to unreliable electricity supply. These are:
While all these elements are presently observed among Nigerian firms, the most common approach has been through private provision. Electricity consumers have responded to the inefficiency of the public utility in charge of electricity supply––the National Electric Power Authority (NEPA) through self-generation. Electricity users, both firms and households, now find it necessary to provide their own electricity in part or in whole to substitute or complement NEPA supply by factoring generator cost in to the overall investment cost, thus raising significantly, the set-up cost for manufacturing firms operating in the country.
(Hunker, 2002) notes that it is important to create an appropriate incentive structure for global infrastructure reliability. Such an incentive structure should motivate a large number of highly diverse users and operators to act in a way that maximizes reliability and security. This incentive structure would be the combination of:
All of these incentives aiming at increasing reliability and security may however be difficult to implement or even to measure. For example, market forces may not be an influential incentive, as benefits of reliability are shared widely across networks, but the costs accrue to individual users. A substantial free rider problem exists –– everyone hopes that everyone else is investing in reliability and security. Furthermore, on regulations (Falch and Tadayoni, 2004) argue that while telecom markets have been liberalized, the institutional framework for spectrum management has largely remained unchanged. In particular, the process of allocation of the spectrum to different applications is still based on technical rather than economic criteria. Market forces are thus not dominant.
Other comments to the incentive structure include that stronger liability cases may only occur when the financial losses are enormous, and most directly caused by an insolvent bad actor (in which case there is nothing much to claim back). The alternative would than be insurance against risks. Also this is difficult, because it is still a fundamental challenge to develop quantitative measures of risk, and creating the data sets necessary to predict or estimate risk levels.
To manage availability and reliability of telecom services, (Falch and Tadayoni, 2004) describe the regulatory framework for assigning frequencies. The process of allocation is done through:
Translating this to an SDI environment, one could come to the following guidelines in the SDI discussions on who will take care – or who has the right - for which GI production with which responsibility:
Conclusions
The reliability perspective, or even more so the reliability-enhancing or avoidance strategy perspective provides new insights in how to manage and give guidance to new developments in SDI’s. From this perspective one can derive an improved understanding of the relation between providers’ and users’ behaviour. If any SDI were to improve spatial data sharing and exchange for the purpose of economic development, than this relation between users and providers will need to be improved. As mentioned, there are various strategies possible to do so, if one were to “learn” from the experiences in the physical infrastructure environment. It seems that not all possible strategies will be useful in the SDI development; yet, a combination of these policy instruments could stimulate both providers and users to work more directly on the reliability and efficacy of the SDI.
References
Managing Spatial Data Infrastructures in Developing Countries: Concepts and Implications`
walter1 T. de Vries
Urban and Regional Planning and Geoinformation Management (PGM)
International Institute for Geoinformation Science and Earth Observation (ITC)
Netherlands
walter1 T. de Vries
Urban and Regional Planning and Geoinformation Management (PGM)
International Institute for Geoinformation Science and Earth Observation (ITC)
Netherlands
Abstract
Infrastructures – both technical and social - are considered to play a key role in facilitating the resumption and acceleration of growth in developing countries. Well performing infrastructure services are crucial for enabling countries to participate in and benefit from global developments. A (geo)spatial data infrastructure (SDI) can be considered a domain specific infrastructure. As such it carries the characteristics of other infrastructures, with peculiarities of the (geo)spatial data domain. This paper examines and defines what sort of infrastructure SDI, and what the implications of this view are for its management. It is argued that in analogy with other infrastructures success depends not only on operational performance but also on the demand for the service: if effective demand is lacking or other services are desired, use or consumption will be less than expected. Effective demand is however dependent on reliability. For users, reliability means that a service has a high probability of being available in the quantity, quality, and at the time required. Substantial changes in reliability will induce changes in users’ behaviour. Users demand different levels of reliability depending on their particular usage activity, and adopt reliability-enhancing strategies when the levels provided do not meet their needs. The reliability, capacity, and cost of infrastructure services at any point depend on the management and maintenance practices of infrastructure suppliers and the dynamic response of all users to infrastructure unreliability.
Managing SDI’s involves therefore assessing the extent to which users adopt such reliability-enhancing strategies. These strategies can in particular be found when comparing business and revenue models of commercial users of spatial information with public providers of spatial information. It is argued that incorporation of real time spatial data use, forceful and diverse business models and interrelated services provision are examples of reliability-enhancing strategies adopted by private users. SDI providers and contributors would need to respond to these strategies. Such a response would need to include management of 1) Maintenance & condition of technical infrastructure; 2) Demand & supply performance; 3) Competitive markets & financial performance; 4) Degree of government intervention; 5) Operational performance. The paper concludes by reviewing what this management would entail from these various perspectives, what would be the implications for those developing countries who are only just starting with SDI development, and which performance indicators would need to be measured to support SDI management.
Introduction
Infrastructures – both technical and social - are considered to play a key role in facilitating the resumption and acceleration of growth in developing countries. Well performing infrastructure services are crucial for enabling countries to participate in and benefit from such developments as the globalisation of trade. A (geo)spatial data infrastructure (SDI) can be considered a domain specific infrastructure. As such it carries the characteristics of other infrastructures, with peculiarities of the (geo)spatial data domain. This paper examines and defines what sort of infrastructure SDI is, and what the implications of this view are for its management. The emphasis will be on the reliability of infrastructure services, and how that has an impact on supply and demand.
Infrastructures and reliability
In analogy with other infrastructures success depends not only on operational performance, but can be evaluated and classified from several perspectives, such as in (Israel, 1992):
- Maintenance & condition of infrastructure
- Demand & supply performance
- Competitive markets – financial performance
- Degree of government intervention
- Operational – operational performance
One key element in any of these perspectives for enhancing efficiency and effectiveness of infrastructure is through an increased focus on reliability of services. Where the first aim of any (information) infrastructure is to enhance access to (information) services, one would find that access alone is not enough. If effective demand is lacking or other services are desired, consumption will be less than expected. For users and beneficiaries, reliability means that a service has a high probability of being available at an affordable cost, and in the quantity, quality, and at the time required. This concept of reliability directly links provision of infrastructure to a specific use, and providers to users. Substantial changes in reliability will induce changes in users’ behaviour, and thus suppliers face however a variety in demands for reliability. Users demand different levels of reliability depending on their particular usage activity, and adopt reliability-enhancing strategies when the levels provided do not meet their needs. The reliability, capacity, and cost of infrastructure services at any point depend on the management and maintenance practices of infrastructure suppliers and the dynamic response of all users to infrastructure unreliability.(Israel, 1992) describes:
Industries producing goods for trade depend on infrastructure as an input. The reliability, capacity, and cost of infrastructure services at any point depend on the management and maintenance practices of infrastructure suppliers and the dynamic response of all users to infrastructure unreliability. Users demand different levels of reliability depending on their particular usage activity, and adopt reliability-enhancing strategies when the levels provided do not meet their needs. The extent to which users adopt such strategies can be used as information to infrastructure providers when selecting optimal investment decisions to improve either the reliability or capacity of infrastructure systems.
For the case of Nigeria (Adenikinju, 2003) notes that poor electricity supply has proved to be the major infrastructure constraint confronting the business sector in Nigeria today. Electricity supply is both unstable and of very low quality. Black out and brown outs are common features of electricity supply in Nigeria. In fact, the average Nigerian firm experiences power failure or voltage fluctuations about 7 times per week, each lasting for about 2 h, without the benefit of a prior warning. This has contributed to the low productivity and low competitiveness of the Nigerian manufacturing sector.
Impact on SDI’s
Applying the above perspectives to SDIs, one could find that:
- Maintenance depends on the ability and capacity to keep the information up to date; the actuality and the completeness of the databases would be performance indicators.
- Demand has until recently mainly depended on the land market, but is increasingly depending on the information market. Supply may not always be in par with this development.
- There has always been little or no competition on the geospatial data infrastructure market. With increasing privatisation worldwide, things are on the move.
- The responsibility of geospatial data infrastructure has been mainly in the realm of public administration so far in most developing countries.
- With increasing demands, operational performance requirements have increased.
In more detail, one could describe these by a number of quality parameters, such as in Table 1 and Table 2:
From a transaction cost theory point of view, enhancing reliability by users is seen as a transaction cost, whereas enhancing reliability by providers is seen as an increase of maintenance cost. The optimum is at the point where the sum of the two is at its minimum, as can be seen in Fig. 1.
Figure: Cost of reliability of GDI
More and more, we are moving to a society in which the management of information––through communications and computer networks––is becoming the key strategic resource that determines the competitiveness of nations and communities. Despite massive investments in information infrastructure, many believe that the full promise of the technological revolution remains unfulfilled––both in the realm of economic development, and in terms of social progress.
And concludes that the key policy challenges of the knowledge-based economy include:
- creating a competitive environment favourable to building a high quality, low-cost information infrastructure;
- encouraging new information highway-based products and services for a global economy that will develop new industries, and create jobs; and
- developing policies that address the socio-cultural issues of the knowledge-based society such as content, access and human resources.
An environment that is however largely unreliable will not generate any economic activity, as unreliable supply will influence manufacturers’ decisions in respect of choice of business, location and input combination. Wherever possible, business activities that are highly (geo-)information intensive are avoided. The short-term response of private firms is than the intensive use of non-(geo-)information inputs.
Bringing this further to the cost and cost efficiency questions, one could argue that the cost of infrastructures would than also include the cost of the reliability-enhancing and/or the cost of avoiding reliability-dependency strategies. This dependency between systems is highlighted by (Hunker, 2002), who notes that:
Global or continental critical infrastructures –– including electric power, telecommunications, and the Internet –– are now the control plane for advanced economies. The occasional failures of these key infrastructures illustrate not only our dependence, but also the unanticipated interdependencies between systems. For example, the 1998 failure of a single telecommunications satellite, Galaxy 4, led to an outage of nearly 90% of all pagers in the United States, while also causing a number of unanticipated failures: many banking and financial services (credit card purchases, automated teller machines) were interrupted, as was communications with doctors and emergency workers.
It relates the cost of providers to that of users if certain strategies from either side are implemented. It also shows that it is not enough to look only at the (static) user needs, but that one needs to take into account the users’ (dynamic) behaviour, or dynamic reaction to certain static or dynamic situations. In absolute terms one could summarize this as in Table 3.
Yet, refinement could be in the question whether cost is (too) high or low. These absolute terms assume only one item of spending, whereas in practice users would always address the question in relation to other spending items. It would thus be better to include a sense of relativity, for example through the issue of “affordability”. Affordable in this context would mean both possible and acceptable (although one could also make a more refined distinction, where one would include the option “acceptable” and “not acceptable”). Users can afford cost if it doesn’t exceed a certain percentage of their overall spending, or if somehow the cost may lead to a certain benefit. How affordability leads to certain users’ behaviour is described by (Cave and Vogelsang, 2003). They suggests that the strategies of potential new entrants to mobile telecom facilities strategies will be influenced by the level of access prices and on the degree of investment in infrastructure which entrants have to make to be eligible to purchase interconnection services at wholesale prices.
Providers, either government of non-government funded, will define affordable in terms of budget or budget constraints, or cost recovery potential. If a certain requirement implies considerable cost, exceeding the budget or cost recovery potential, providers may be forced to deny any investment to comply with such requirement. The issue of “affordability” also incorporates the dynamics of a situation. What may be affordable now, may not necessarily be affordable in the future (Table 4 and Table 5).
Management response
Following the emphasis on reliability, managing SDI’s involves assessing the extent to which users adopt such reliability-enhancing strategies. Some of these strategies can be found when comparing business and revenue models of commercial users of spatial information with public providers of spatial information. A number of commercial spatial services providers have incorporated real time spatial data use, forceful and diverse business models and interrelated services provision. examples of reliability-enhancing strategies adopted by private users.
In theory the management response could be visualised by the following change in operations and activities:
Figure 2. Shift in reliability perspective
Globally the public sector is under increasing stress to reduce their budgets and scale down their activities, which could be outsourced and privatized. Part of these activities includes infrastructural works. One of the major reasons why many infrastructures in developing countries are not functioning from an public sector point of view is because they have lost value due to the lack of maintenance. The same would be true for systematic data collections and a SDI. SDI being in the realm of public interests, this maintenance is often expected from the public sector. Yet, even in countries where data are being upgraded, for example through donor incentives or systematic Land Information Systems projects (example Nepal), often one sees a systematic bias in favor of new construction and design at the expense of maintenance of available records. Most of the value of the SDI is derived from its capability of maintenance. Part of the problem is the failure to include beneficiaries in the (information) system design, top-down or donor driven approaches that emphasize complex ICT solutions. Problem is obviously a focus on short-term technical rationality rather than long-term process of institutional development. In that sense, developments in SDIs follow a similar pattern as most other development projects.
(Adenikinju, 2003) for the Nigerian case describes that there are essentially five ways by which firms may respond to unreliable electricity supply. These are:
- choice of location,
- factor substitution,
- private provision,
- choice of business and
- output reduction.
While all these elements are presently observed among Nigerian firms, the most common approach has been through private provision. Electricity consumers have responded to the inefficiency of the public utility in charge of electricity supply––the National Electric Power Authority (NEPA) through self-generation. Electricity users, both firms and households, now find it necessary to provide their own electricity in part or in whole to substitute or complement NEPA supply by factoring generator cost in to the overall investment cost, thus raising significantly, the set-up cost for manufacturing firms operating in the country.
(Hunker, 2002) notes that it is important to create an appropriate incentive structure for global infrastructure reliability. Such an incentive structure should motivate a large number of highly diverse users and operators to act in a way that maximizes reliability and security. This incentive structure would be the combination of:
- Market Forces
- Regulation,
- Liability and Contracts
- Voluntary Standards and Best Practices
- Insurance
- Public disclosure
- Reputation/Ratings
- Network provider standards
All of these incentives aiming at increasing reliability and security may however be difficult to implement or even to measure. For example, market forces may not be an influential incentive, as benefits of reliability are shared widely across networks, but the costs accrue to individual users. A substantial free rider problem exists –– everyone hopes that everyone else is investing in reliability and security. Furthermore, on regulations (Falch and Tadayoni, 2004) argue that while telecom markets have been liberalized, the institutional framework for spectrum management has largely remained unchanged. In particular, the process of allocation of the spectrum to different applications is still based on technical rather than economic criteria. Market forces are thus not dominant.
Other comments to the incentive structure include that stronger liability cases may only occur when the financial losses are enormous, and most directly caused by an insolvent bad actor (in which case there is nothing much to claim back). The alternative would than be insurance against risks. Also this is difficult, because it is still a fundamental challenge to develop quantitative measures of risk, and creating the data sets necessary to predict or estimate risk levels.
To manage availability and reliability of telecom services, (Falch and Tadayoni, 2004) describe the regulatory framework for assigning frequencies. The process of allocation is done through:
Translating this to an SDI environment, one could come to the following guidelines in the SDI discussions on who will take care – or who has the right - for which GI production with which responsibility:
Conclusions
The reliability perspective, or even more so the reliability-enhancing or avoidance strategy perspective provides new insights in how to manage and give guidance to new developments in SDI’s. From this perspective one can derive an improved understanding of the relation between providers’ and users’ behaviour. If any SDI were to improve spatial data sharing and exchange for the purpose of economic development, than this relation between users and providers will need to be improved. As mentioned, there are various strategies possible to do so, if one were to “learn” from the experiences in the physical infrastructure environment. It seems that not all possible strategies will be useful in the SDI development; yet, a combination of these policy instruments could stimulate both providers and users to work more directly on the reliability and efficacy of the SDI.
References
- Adenikinju, A.F., 2003. Electric infrastructure failures in Nigeria: a survey-based analysis of the costs and adjustment responses. Energy policy, 31(14): 1519-1530.
- Cave, M. and Vogelsang, I., 2003. How access pricing and entry interact. Telecommunications policy, 27(10-11): 717-727.
- Falch, M. and Tadayoni, R., 2004. Economic versus technical approaches to frequency management. Telecommunications policy, 28(2): 197-211.
- Hunker, J., 2002. Policy challenges in building dependability in global infrastructures. Computers & Security, 21(8): 705-711.
- Israel, A., 1992. Issues for infrastructure management in the 1990s. 171, World Bank.
- Johnston, D.L., 1998. Open networks, electronic commerce and the global information infrastructure. Computer standards & interfaces, 20(2-3): 95-99.