Insights from Exploration into Cloud-based Simulation
Charles G. Sanders, PhD Alion Science and Technology Corporation 500 West Riverview Drive Suffolk, VA 23434 757-810-3708
[email protected]
Keywords: Cloud computing, Cloud-based simulation, M&S as a Service (MSaaS), modeling framework.
ABSTRACT: In response to recent Department of Defense(DoD) interest in cloud computing, a group of M&S technical experts from across the DoD Modeling and Simulation (M&S) community met for several technical exchange meetings (TEMs) to share experiences, challenges, expected benefits, and approaches for running simulation from and/or through the cloud. Insights were discussed, but some questions still need to be answered. This paper reviews recent efforts to explore to what degree the M&S community is ready to run simulation in or through the cloud, and if the cloud service providers are ready to support the M&S community. Various aspects of distributed simulation are explored, such as virtualization, federations, modeling frameworks, data management, and standards. This paper also raises questions regarding how M&S standards may be impacted by cloud-based simulation.
1. Introduction Organizations across the Department of Defense (DoD) are beginning to explore various aspects of running simulations through the cloud. Given the recent DoD Chief Information Officer (CIO) emphasis [1] on leveraging cloud computing and Joint Staff initiative to transition joint training simulations to the cloud with M&S as a Service, a series of technical exchange meetings were held to engage M&S experts from across DoD and industry with experience in running simulation through or from the cloud to learn if anything should be done with policy or standards to facilitate migration to cloud-based simulation in a cost effective way. 1.1 Cloud Computing The Chairman of the Joint Chiefs of Staff in 2013, declared that the Department needs to transition to a Joint Information Environment (JIE) leveraging cloud services to change the way the Department assembles, configures, and uses new and legacy information technologies [2]. The JIE framework is stated to provide the information environment flexibly to create, store, disseminate, and access data, applications, and other computing services when and where needed. In response to this direction, the Joint Staff began developing a new Joint Training
Enterprise Architecture which will leverage cloud computing and M&S as a service technologies to deliver expanded, flexible, and accessible collection of enterprise tools that will enable Joint force readiness through training, exercises, and mission rehearsal. 1.2 Simulation in the Cloud Advancements in computing have created many possibilities for organizations [3]. Until recently, a main concern of applications developers was deployment and hosting of applications considering acquisition of resources with a fixed capacity to handle the expected application traffic demand and the installation, configuration, and maintenance of the whole stack of the platform supporting the application. With the advent of the Cloud, application deployment and hosting has become flexible, easier, and less costly with the use of pay-per-use fee model by Cloud providers. Cloud Computing is a best-fit for applications where users have heterogeneous, dynamic, and competing quality of service requirements [3]. Different applications have different performance, workload, and dynamic application scaling requirements; however, these characteristics, service models and deployment models create a vague situation when we use Cloud to host applications, such as simulations. It creates complex provisioning, deployment, and configuration requirements. There are several efforts ongoing to leverage cloud computing to support simulation, and it appears there are also different perspectives on what
cloud-based simulation is and how best to migrate to that environment.
2. Common Concerns From the cloud technical exchange meetings, a number of common concerns or lessons learned with cloud-based simulation emerged and are discussed below. 2.1 Latency Attempts to run simulation in the cloud to date have been to create virtual machines for distributed simulation. The U.S. Army Program Executive Office for Simulation, Training, & Instrumentation (PEOSTRI) found that virtualizing One SemiAutomated Forces (OneSAF) did eliminate the need to send equipment and software to remote locations, but also created network latency issues when a large number of VMs were established. Latency emerged because of the large simulations construct and associated data messaging requirements [4].
for milCloud, there was concern that some DoD M&S users would be located a large distance from the data center supporting their participation in a cloud-based simulation, which raises the potential for latency issues. The milCloud representative stated there are plans for additional CDCs in the future. A standing question is whether milCloud, or any other cloud service provider, can deliver the performance – both compute and network – to support M&S driven exercises and events. 2.4 Commercial Tools (i.e., VMWare licensing – cost). There was some concern expressed about the cost of licensing for commercial tools, given the information assurance (IA) restrictions on open-source tools and need for certain tools to operate in the Cloud. A wider understanding of open source use by the National Security Agency (NSA) and the U.S. Army Intelligence & Security Command (INSCOM) would be helpful. The DoD cloud service provider, milCloud, uses VMWare and provides licenses as part of the service.
When considering cloud service providers, such as milCloud, there is concern that milCloud was built based on common Information Technology tools, and may not be able to support the bandwidth requirements of current M&S tools. M&S tools currently are run as federations of several simulations in centralized data centers. DISA is planning to expand the number of Core Data Centers (CDCs), which may alleviate some of the potential issues if tools are available to manage participant location relative to CDC location. Being able to support compute intensive applications and systems prevalent in the M&S ecosystem is a concern; in particular support for graphics processor units (GPUs) in virtual machines is a key requirement.
2.5 Configuration inconsistencies
2.2 Non-composable simulations not suited for cloud
2.6 User requirements management
There was general agreement among the meeting participants that migrating monolithic (nondecomposable) M&S tools to the Cloud would not provide significant savings, and would most likely be more difficult (costly) given the above mentioned issue. Breaking apart the large simulations into smaller components, or services, was discussed as one way to alleviate the issue. This raises the question of whether legacy simulations should be replaced with cloudenabled services.
2.7 Software updates
2.3 Data center requirements (access and proximity to user) Due to the latency concerns, there was general agreement that the user access to the cloud should be relatively close to the data center supporting the simulation. However, with only two core data centers
There was general agreement that each organization typically has a slightly different version or configuration of the same tools, which makes migration to the Cloud challenging. This is actually not unique to the cloud. The M&S community already experiences challenges with configuration management for software used in different organizations. However, migration to cloud-based simulation, especially if M&S as a service is embraced, would make configuration management much more important. Understanding how commercial industry has employed the cloud to improve enterprise configuration control and change management would be useful. There was a general agreement that some user requirements change more frequently than the M&S developers can respond. Can the cloud enable better service by enabling more responsive development, as has been seen in commercial industry? Concern was raised about how rapidly or irregularly some tools, such as VMWare, are updated, and the associated integration and IA requirements that are generated with each change. 2.8 Performance management tools There was general agreement that some tools need to be developed to monitor the performance of cloud-based simulation for potential problems such as latency. There was also general agreement that there needs to be some cloud enabled, “big data” influenced data
collection tools to modernize and enhance After Action Review (AAR). 2.9 Return on Investment Few organizations have the metrics or tools to measure cost savings or enhanced performance of running M&S tools from the Cloud. This makes investment decisions more difficult to justify. Understanding commercial case studies and experiments to understand how the cloud can streamline M&S events would be useful. Complicating this issue is the realization that a number of cloud service providers (CSPs), in addition to milCloud, are available, but not well understood with respect to cost and services provided. As more CSPs meet the DoD Security Requirements Guide and are certified as providers for DoD, better analysis should be possible. 2.10 Need new V&V policies and processes for cloud-based There was general agreement that, with the vision of composable and flexible models and services from the cloud, the current rules require full V&V and for each instance, a set of tools and data are configured for a given event. The organizations present stated they are not funded to conduct V&V each time a set of models and/or services are configured or changed in an event. 2.11 Cyber Security rules and processes. The current IA rules are based on individual instantiations of M&S tools for each event, and not on the potentially persistent capabilities of cloud-based simulations. Also, there is increased cost associated with assessing each composable service vice accreditation of a single traditional simulation. 2.12 Standards or Standard tools – There was general agreement that there should be some standardization for the data, models, and event planning and execution tools that would be run in the Cloud, so as to maintain interoperability and enhance anticipated cost savings.
3. Considerations for cloud-based simulation According to Tolk and Mittal [5] composable cloudbased simulations require “conceptual alignment of data and harmonization of processes”. They also argue, and the TEM participants agree, that virtualization of simulation applications is not sufficient for composable cloud-based M&S services. Typically, a simulation application is built with both functionality and representation of the environment and entities to be simulated [5]. This is one place where duplication of efforts and resources are present,
as each simulation is built to be standalone and do not share common resources. Therefore, included in the conceptual alignment and harmonization for composable cloud-based simulation is the need to separate the creation of functionality from representation. This will facilitate development of a common foundational functional simulation infrastructure that can use all the various representations (applications) developed by and used by any DoD component in any way deemed necessary for its intended use. In a sense, we are talking about doing for DoD M&S what Apple did for personal computing and the smartphone.
4. Potential impact of cloud on M&S standards The Joint Staff is documenting the requirement that the Joint Training Synthetic Environment (JTSE IS ICD submitted, awaiting approval) will require a common set of open, net-centric, international standards and protocols to support tool interoperability and reuse. How this impacts the DoD M&S community is yet to be known. A common theme throughout the technical exchange meetings was the realization that, because large simulations are not well-suited for running through the cloud, an alternative approach to building models and simulations as services would be required with a common modeling framework, data, and simulation services to facilitate operation of the models and services for events. This also leads to the realization that the simulation interoperability focus needs to shift down from federations to a lower level, perhaps requiring a standard modeling framework. Several new modeling approaches were explored in the TEMs [6][7][8], all of which show promise but require further examination and testing.
5. Unanswered questions In an effort to guide future research, a list of research questions was generated based on what the group believes need to be addressed to better understand cloud-based simulation. The group proposes design of tests to develop better understanding and address these questions. 5.1 What common services should be created? Some would be considered as infrastructure services versus applications or modeling services. 5.2 What existing DoD tools or services are already cloud and/or MSaaS ready? 5.3 Is there a core group of M&S services that can have general utility and provide for more cost effective use and reuse of M&S assets?
5.4 What available open source or commercial tools or software are ideal for MSaaS?
working with the Defense Modeling and Simulation Coordination Office (DMSCO) in OUSD/AT&L. A long time practitioner of M&S in training and learning applications, he is the facilitator of the Technical Exchange Meetings focused on Cloud-based Simulation. He received his Masters of Science in Information Resources Management from Syracuse University and Doctor of Philosophy in Organization Development from Regent University.
5.5 What are the essential components of the required MSaaS foundational infrastructure? 5.6 What DoD and/or industry standards are required to make MSaaS paradigm effective and affordable?
6. References [1] DoD CIO Memo of 26 Sep 2013, “Joint Information Environment Implementation Guidance”. [2] M. Dempsey: “The Joint Information Environment White Paper”. The Joint Staff, 22 January 2013. [3] M. Soni: “Cloud computing and simulation – Modelling and simulation of cloud environment”. Researcher’s Blog: Cloud Computing, 2014. Available at: http://cleanclouds.com/2014/01/cloud-computingsimulation-modelling-simulation-cloudenvironment/. [4] A. Kapadia, N. Belfar, O. Tran, C. May, R. Wittman, W. Beebe, C. Holmes, R. Osborne, S. Webster, S. Berglie, Y. Hanley, & M. Smith: “Providing OneSAF-based Prototype Simulation Services and Standards into the U.S. Army Command Post Computing Environment,” In Proceedings of the 2013 Fall Simulation Interoperability Workshop. [5] A. Tolk, & S. Mittal: “A Necessary Paradigm Change to Enable Composable Cloud-Based M&S Services”, In Proceedings of the 2014 Winter Simulation Conference. [6] R. Kewley, & S. Sapol: “Executable Architecture for Systems Engineering – Distributed Modeling Framework”, In Proceedings of the 2014 Fall Simulation Interoperability Workshop. [7] J. Steinman: “The Roadmap”, In Proceedings of the 2013 Fall Simulation Interoperability Workshop. [8] C. Winfrey, B. Baldwin, M. Cummings, & P. Ghosh: “OSD: An Evolutionary System of Systems Framework for Modeling and Simulation”, NAVSEA Warfare Center Dahlgren Publication ID#NSWCDD-PN-1400006.
7. Author Biography CHARLES SANDERS is a Principal M&S Analyst for Alion Science and Technology Corporation
