Net-Centric Operations for National Security Space

Craig A. Lee

Aerospace is helping the Department of Defense design a global system that will enable the computing and data resources of virtually all connected platforms and components, from satellites to laptop computers, to interoperate as a seamless whole.

The term "net-centric" suggests system operations that are simply designed around the use of computer networks; however, the phrase means much more than that. It entails a new approach to system design based on a system's role in a heterogeneous "network of networks," rather than as an independent computational system. This approach has some practical engineering implications in terms of defining a common framework for how component systems are designed, deployed, and made to interact.

The Network-Centric Operations and Warfare Reference Model defines nine core enterprise services that will connect communities of interest (COIs) across DOD war fighting and business functions and include national intelligence agencies.

This is the basic concept behind the Global Information Grid that the Department of Defense (DOD) has been developing. The Grid will be the information infrastructure that integrates all DOD activities, including intelligence, war fighting, and routine business processes. Sensors on the ground, in the air, and on orbit will be connected with collaborative decision-making systems that form plans of action that are then assigned to resources that work together to deliver a response. Field data and intelligence will be processed together with existing archival data to develop long-term strategies and policies. Supplies, logistics, and reporting will also be orchestrated to ensure efficient operation.

Aerospace has been helping the DOD identify and surmount the technical challenges of implementing such a comprehensive system of systems. In particular, Aerospace has been contributing expertise in large-scale architecture planning while participating in the development of relevant information technology standards and guidelines.

Service-Oriented Architectures

The Global Information Grid will rely on a comprehensive service-oriented architecture—a conceptual system model that emphasizes the deployment of reusable services and machine resources. Service-oriented architectures require that components observe specific standards for how one system requests a computational service and how another system provides it. They can be implemented in many different ways, but Web and Grid service standards are emerging as the favored paradigm.

In February 2003, the Defense Department issued an initial draft of the Network-Centric Operations Warfare Reference Model, which defines the Grid in terms of nine core enterprise services—messaging, discovery, mediation, collaboration, storage, information assurance, user assistance, enterprise service management, and application. (The Reference Model was revised in September 2005 to incorporate the latest developments in Web and Grid service standards.)

Messaging provides the basic capability for users and systems to exchange information. Discovery enables search queries to be formed and posed to catalogs, directories, and registries, which return the matching data and service descriptions. Mediation enables data or other services to be translated, aggregated, integrated, correlated, fused, brokered, published, or transformed in some fashion. Collaboration includes synchronous activity, such as audio/video conferencing, and asynchronous activity, such as e-mail. Storage entails the naming and arranging of billions of files from anywhere in the Grid. This will require extensive metadata catalogs and storage "virtualization," where data are referenced by name or attribute without knowledge of where they physically reside. Information assurance covers the security, robustness, and quality of service, and must address issues such as authentication, authorization, data privacy, data integrity, and nonrepudiation of transactions. User assistance will be available in the form of decision tools, capabilities that learn user preferences, and context-sensitive help. Enterprise service management covers a broad spectrum of developing, deploying, monitoring, and repairing specific services. The applications are the various national defense programs that will use these Grid capabilities.

While this reference model brings more technical structure to the issue of "what is the Global Information Grid," the process of mapping this high-level architecture to concrete implementations remains to be done. However, a number of selected pilot programs have been started. For example, the DOD is running the Business Management Modernization program to assist development of the business enterprise architecture. The Defense Information Systems Agency (DISA) is executing the Network-Centric Enterprise Services program to provide a service-oriented architecture that includes collaboration, content discovery and delivery, and a developers' network. The agency has also been running the Global Information Grid Bandwidth Expansion project, an upgrade to the Defense Information System Network intended to provide secure, robust network connectivity across almost 100 sites by the end of 2005. Aerospace has been instrumental in specifying the Bandwidth Expansion project architecture, in conjunction with the Transformational Communications Satellite (TSAT) program, which will be the other major backbone provider for the Global Information Grid.

The Grid may be revolutionary in concept, but deployment will require an evolutionary approach. Existing systems will have to be integrated with this new dynamic network, but most were conceived as individual entities, without any distributed computing standards in mind. Hence, extensibility and interoperability remain problematic. These existing systems will need Grid-compliant interfaces built for them. As for new systems, they will need to employ compatible design elements to achieve the necessary capability and interoperability. Hence, program managers, system designers, and engineers need to understand Grid concepts when developing new satellite ground systems.

An important goal for Aerospace is to ensure that national security space requirements are met when the Global Information Grid core enterprise services are matched with the identified target technologies being developed commercially.

Standards and Best Practices

The concepts underlying the Global Information Grid are not unique to defense operations. In fact, many core concepts derive from a movement in the commercial sector to promote e-commerce and efforts in the research community to link distributed computing resources into a larger, more powerful arrays. Based on experiences of these communities, various standards organizations are codifying the emergent best practices. Aerospace is playing a critical role in ensuring that national security space goals are represented in these emerging standards. For example, Aerospace serves as the Area Director for Industrial Applications in the Global Grid Forum, responsible for developing new industrial application domains for grid technology and connecting them with the standards process.

An important development in the Global Grid Forum is the Open Grid Services Architecture. This architecture extends the notion of Web services to define service "factories" that can create new services on desired computing resources and manage how long they will be available at each location (that is, they can control service lifetime). This is an essential system management function. To support this new architecture, the Global Grid Forum has also defined the Web Services Resource Framework, which also allows a client to manage the location of data resources by remote Web services. This has tremendous implications for workflow management and fault tolerance because the system can manage the flow of data among service locations and also manage the location of data replicas and restart services when necessary to recover from failures.

Because Web and Grid service standards are so closely related, the Global Grid Forum is pursuing coordination among many standards bodies, including the World Wide Web Consortium (W3C) and the Organization for the Advancement of Structured Information Standards (OASIS). As a case in point, the Web Services Resource Framework was initially defined by the Open Grid Services Architecture Working Group within the Global Grid Forum but sent through the standardization process via OASIS to gain acceptance from the larger Web services community.

Aerospace is also a member of the Network-Centric Operations Industry Consortium, a nonprofit organization (led by the defense industry) founded to promote net-centric operations while clarifying appropriate business models and practices. Hence, in addition to developing tools for framework development and business analysis, the consortium has been investigating how to track accountability, licensing, and service models that allow business competitors to operate in a shared, government-hosted environment. As a member of this consortium, Aerospace is investigating the mapping of common enterprise services onto the emerging Web/Grid service architectures. Most notably, Aerospace is a charter member of the newly formed Network-Centric Operations Industry Consortium Ground Station Working Group, which will be defining a net-centric ground station reference model. As part of this work, Aerospace will be promoting common developments between the consortium and relevant standards bodies, such as the Global Grid Forum, W3C, and OASIS.

Space Program Applications

On-orbit assets, and the data they produce, will be an integral part of the Global Information Grid. Individual space programs must determine how they will use resources such as processors, storage, communications, and data. They must identify which services they will expect to use and which services they expect to provide. Resource-sharing policies must be defined with effective enforcement methods. Currently, GPS-III, TSAT, and the Air Force Satellite Control Network all have future Grid requirements that Aerospace has participated in defining.

As this work proceeds, Aerospace must identify capability and technology gaps as early as possible by systematically comparing mission requirements with the emerging Web and Grid service standards. Aerospace must then identify remedies and fold them into the net-centric operations process. The acquisition process will also have to change to reflect the system of systems that constitutes the shared environment of the Global Information Grid.