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Extending Portico HLA to Federations of Federations with Transport Layer Security



Thomas Roth, Martin Burns, Tim Pokorny


The Internet of Things (IoT) promises to connect and manage an unprecedented number of heterogeneous devices that are not designed to interoperate as a system. Modeling and Simulation of IoT will face new challenges in the representation of this scale because an accurate model must consider the characteristics of each unique IoT device in the system. In addition, hardware-in-the-loop simulation of IoT will produce massive quantities of information that can overwhelm the processing power of the low-power devices often deployed in these systems. This paper introduces a new infrastructural component called a Forwarder to the Portico implementation of the High-Level Architecture (HLA). It transforms the flat structure of HLA into a hierarchical structure where federates are partitioned into different clusters that communicate through their respective Forwarders. A Forwarder acts as both a data router between the different clusters in the federation, and a firewall that limits the amount of information that traverses the boundaries of its local cluster. Using this approach, Portico now has a scalable architecture suited to IoT that simulates a federation of hierarchical federations. A novel aspect of the Forwarder design is that the scalability of HLA traffic flow is amplified by the inherent function of traditional Internet Switch fabric technology. This technology resulted from a collaboration between the United States National Institute of Standards and Technology and Portico's core development team at Calytrix Technologies. The new Portico 2.2.0 will be used in the Universal CPS Environment for Federation (UCEF) and in other projects worldwide.
Conference Dates
September 9-14, 2018
Conference Location
Orlando, FL, US
Conference Title
2018 Fall Simulation Innovation Workshop


cyber-physical systems, internet of things, high level architecture, hierarchical federations


Roth, T. , Burns, M. and Pokorny, T. (2018), Extending Portico HLA to Federations of Federations with Transport Layer Security, 2018 Fall Simulation Innovation Workshop, Orlando, FL, US, [online], (Accessed July 17, 2024)


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Created September 10, 2018, Updated October 12, 2021