Kul Bhasin

Space Internet architectures and technologies for NASA enterprises

NASAs future communications services will be supplied through a space communications network that mirrors the terrestrial Internet in its capabilities and flexibility. The notional requirements for future data gathering and distribution by this Space Internet have been gathered from NASAs Earth Science Enterprise (ESE), the Human Exploration and Development in Space (HEDS), and the Space Science Enterprise (SSE). This paper describes a communications infrastructure for the Space Internet, the architectures within the infrastructure, and the elements that make up the architectures. The architectures meet the requirements of the enterprises beyond 2010 with Internet compatible technologies and functionality. The elements of an architecture include the backbone, access, inter-spacecraft, and proximity communication parts. From the architectures, technologies have been identified which have the most impact and are critical for the implementation of the architectures.

Developing Architectures and Technologies for an Evolvable NASA Space Communication Infrastructure

Space communications architecture concepts play a key role in the development and deployment of NASAs future exploration and science missions. Once a mission is deployed, the communication link to the user needs to provide maximum information delivery and flexibility to handle the expected large and complex data sets and to enable direct interaction with the spacecraft and experiments. In human and robotic missions, communication systems need to offer maximum reliability with robust two-way links for software uploads and virtual interactions. Identifying the capabilities to cost effectively meet the demanding space communication needs of 21 st century missions, proper formulation of the requirements for these missions, and identifying the early technology developments that will be needed can only be resolved with architecture design. This paper will describe the development of evolvable space communication architecture models and the technologies needed to support Earth sensor web and collaborative observation formation missions; robotic scientific missions for detailed investigation of planets, moons, and small bodies in the solar system; human missions for exploration of the Moon, Mars, Ganymede, Callisto, and asteroids; human settlements in space, on the Moon, and on Mars; and great in-space observatories for observing other star systems and the universe. The resulting architectures will enable the reliable, multipoint, high data rate capabilities needed on demand to provide continuous, maximum coverage of areas of concentrated activities, such as in the vicinity of outposts inspace, on the Moon or on Mars.

NASA Integrated Space Communications Network

The NASA Integrated Network for Space Communications and Navigation (SCaN) has been in the definition phase since 2010. It is intended to integrate NASA s three existing network elements, i.e., the Space Network, Near Earth Network, and Deep Space Network, into a single network. In addition to the technical merits, the primary purpose of the Integrated Network is to achieve a level of operating cost efficiency significantly higher than it is today. Salient features of the Integrated Network include (a) a central system element that performs service management functions and user mission interfaces for service requests; (b) a set of common service execution equipment deployed at the all stations that provides return, forward, and radiometric data processing and delivery capabilities; (c) the network monitor and control operations for the entire integrated network are conducted remotely and centrally at a prime-shift site and rotating among three sites globally (a follow-the-sun approach); (d) the common network monitor and control software deployed at all three network elements that supports the follow-the-sun operations.

NASA's Integrated Space Communications Architecture

The Space Communications and Navigation (SCaN) Program was formed about three ago by NASA in order to create an integrated space communications and tracking capability for the Agency. Previously, the three major space communications networks were managed largely independently with relatively low levels of reuse of developments and varying levels of common approaches, processes, tools, and standards utilized across them. This network specific approach has served the Agency well for nearly fifty years; however, as NASA moves into the next decade of space operation, the Agency is striving to do more within a constrained budget. In order to achieve the vision for an integrated network for NASA missions, a team was chartered in March 2008 to develop an integrated architecture roadmap. The architecture developed provides for a scalable capability which provides: an integrated service-based architecture; space internetworking throughout the solar system; International interoperability; assured safety and security of missions; and significant increases in bandwidth. The architecture makes extensive use of new technologies such as optical communications, Delay Tolerant Networking, software defined radios as well as utilization of extended high rate Ka-band communications and international standards. A logical roadmap was developed to implement the architecture with numerous key Architecture Decision Points to ensure that new technologies are mature enough to phase into operations, as well as to select appropriate capacities to meet mission needs. This paper will provide an overview of the architecture, its key attributes, and the roadmap to implement the new vision.

IP Communication and Distributed Agents for Unmanned Autonomous Vehicles

Unmanned Autonomous Vehicles (UAVs) extend the reach of human activities and exploration, and are currently of utmost interest to NASA Mars missions and Earth Science enterprises. At present, fully autonomous machines are poorly equipped to survive in realistically complex and uncertain environments. However, incremental progress and useful intermediate results can be achieved through collaboration between local autonomy and remote supervision. In this paper, we submit that these objectives can be accomplished through the use of IP (Internet Protocol) coupled with • An appropriate design of the local controller, • Realand non-real-time middleware, and • Agent-based software. This paper describes our experience in the application of these methodologies for the remote supervision of intelligent machines.

Architecting the Communication and Navigation Networks for NASA's Space Exploration Systems

NASA is planning a series of short and long duration human and robotic missions to explore the Moon and then Mars. A key objective of the missions is to grow, through a series of launches, a system of systems communication, navigation, and timing infrastructure at minimum cost while providing a network-centric infrastructure that maximizes the exploration capabilities and science return. There is a strong need to use architecting processes in the mission pre-formulation stage, to describe the systems, interfaces, and interoperability needed to implement multiple space communication systems that are deployed over time, yet support interoperability with each deployment phase and with 20 years of legacy systems. In this paper we present a process for defining the architecture of the communications, navigation, and networks needed to support future, space explorers with the best adaptable and evolable network-centric space exploration infrastructure. The process steps presented are: 1) architecture decomposition, 2) defining mission systems and their interfaces, 3) developing the communication, navigation, networking architecture, and 4) integrating systems, operational and technical views and viewpoints. We demonstrate the process through the architecture development of the communication network for upcoming NASA space exploration missions.

Unified approach to modeling & simulation of space communication networks and systems

Network simulator software tools are often used to model the behaviors and interactions of applications, protocols, packets, and data links in terrestrial communication networks. Other software tools that model the physics, orbital dynamics, and RF characteristics of space systems have matured to allow for rapid, detailed analysis of space communication links. However, the absence of a unified toolset that integrates the two modeling approaches has encumbered the systems engineers tasked with the design, architecture, and analysis of complex space communication networks and systems. This paper presents the unified approach and describes the motivation, challenges, and our solution — the customization of the network simulator to integrate with astronautical analysis software tools for high-fidelity end-to-end simulation.

Lunar Relay Satellite Network for Space Exploration: Architecture, Technologies and Challenges

PresciPoint Solutions, L.L.C., Littleton, CO, 80123 NASA is planning a series of short and long duration human and robotic missions to explore the Moon and then Mars. A key objective of these missions is to grow, through a series of launches, a system of systems infrastructure with the capability for safe and sustainable autonomous operations at minimum cost while maximizing the exploration capabilities and science return. An incremental implementation process will enable a build-up of the communication, navigation, networking, computing, and informatics architectures to support human exploration missions in the vicinities and on the surfaces of the Moon and Mars. These architectures will support all space and surface nodes, including other orbiters, lander vehicles, humans in spacesuits, robots, rovers, human habitats, and pressurized vehicles. This paper describes the integration of an innovative MAC and networking technology with an equally innovative position-dependent, data routing, network technology. The MAC technology provides the relay spacecraft with the capability to autonomously discover neighbor spacecraft and surface nodes, establish variable-rate links and communicate simultaneously with multiple in-space and surface clients at varying and rapidly changing distances while making optimum use of the available power. The networking technology uses attitude sensors, a time synchronization protocol and occasional orbit-corrections to maintain awareness of its instantaneous position and attitude in space as well as the orbital or surface location of its communication clients. A position-dependent data routing capability is used in the communication relay satellites to handle the movement of data among any of multiple clients (including Earth) that may be simultaneously in view; and if not in view, the relay will temporarily store the data from a client source and download it when the destination client comes into view. The integration of the MAC and data routing networking technologies would enable a relay satellite system to provide end-to-end communication services for robotic and human missions in the vicinity, or on the surface of the Moon with a minimum of Earth-based operational support.

A Framework for an Intelligent Internet Protocol for a Space-Based Internet

An intelligent mobile agent is an autonomous decision maker that moves from node to node, gathering information, and then takes actions based on the gathered information to achieve its purpose. The agent uses the knowledge it acquires to determine future actions. This paper describes a framework for an IP-based protocol that allows intelligent mobile agents to function within the network layer. This framework will provide an autonomous, flexible system with the ability to seamlessly handle space-based Internet routing; a volatile, sometimes unpredictable environment. We extend the capabilities of the Internet Protocol (IP) to allow and facilitate the existence of intelligent mobile agents within the network layer, creating what we term Intelligent Internet Protocol (IIP).

Surface Communications Network Architectures for Exploration Missions

contents include the following: 1. Requirements: Missions. Infrastructure. End-to-End. 2. Operational View: System View. Nodes. Interfaces. Links. Network Design. Technologies.