International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / The CCSDS has developed the “CCSDS File Delivery Protocol” (CFDP), as a disruption/delay tolerant file transfer protocol. CFDP allows an automatic, reliable file transfer between spacecraft and ground (in both directions) designed to support the operation of spacecraft by means of file transfer and remote file system management. To support the development and fielding of the protocol in an international and cross-supporting environment, an international, inter-operability test program has been developed and successfully executed. First phase testing involved five independent implementations of the Core Procedures of the protocol. The second phase tests involve multi-hop transferring of files using the Extended Procedures. The third phase involves the testing of the SFO Procedures. The latter two phases involved two independent protocol implementations, namely, those of ESA and JPL. This paper constitutes a final report on the process of testing, the test results, the experience gained, and the resulting plans to extend this methodology to other areas within the CCSDS.

International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / The Consultative Committee for Space Data Systems (CCSDS) developed the CCSDS File Delivery Protocol (CFDP) to provide reliable delivery of files across space links. Space links are typically intermittent, requiring flexibility on the part of CFDP. Some aspects of that flexibility will be highlighted in this paper, which discusses the planned use of CFDP on the Global Precipitation Measurement (GPM) mission. The operational scenario for GPM involves reliable downlink of science data files at a high datarate (approximately 4 megabits per second) over a space link that is not only intermittent, but also one-way most of the time. This paper will describe how that scenario is easily handled by CFDP, despite the fact that reliable delivery requires a feedback loop.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Reliable delivery of data products is often required across space links. For example, a NASA mission will require reliable delivery of images produced by an on-board detector. Many missions have their own (unique) way of accomplishing this, requiring custom software. Many missions also require manual operations (e.g. the telemetry receiver software keeps track of what data is missing, and a person manually inputs the appropriate commands to request retransmissions). The Consultative Committee for Space Data Systems (CCSDS) developed the CCSDS File Delivery Protocol (CFDP) specifically for this situation. CFDP is an international standard communication protocol that provides reliable delivery of data products. It is designed for use across space links. It will work well if run over the widely used CCSDS Telemetry and Telecommand protocols. However, it can be run over any protocol, and will work well as long as the underlying protocol delivers a reasonable portion of the data. The CFDP receiver will autonomously determine what data is missing, and request retransmissions as needed. The CFDP sender will autonomously perform the requested transmissions. When the entire data product is delivered, the CFDP receiver will let the CFDP sender know that the transaction has completed successfully. The result is that custom software becomes standard, and manual operations become autonomous. This paper will consider various ways of achieving reliable file delivery, explain why CFDP is the optimal choice for use over space links, explain how the core protocol works, and give some guidance on how to best utilize CFDP within various mission scenarios. It will also touch on additional features of CFDP, as well as other uses for CFDP (e.g. the loading of on-board memory and tables).

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A spacecraft complying with the CCSDS Packet Telemetry standard generates telemetry data as a stream of packets. Generally, each packet has different requirements for data transfer characteristics (such as delay and reliability). These requirements are called Quality of Service (QoS) requirements. This paper proposes an extension to the CCSDS Packet Telemetry standard to specify QoS requirements of each packet. The method proposed in this paper is to associate with each packet (1) a level of delay tolerance and (2) a level of loss tolerance. This paper shows how packets should be handled based on this QoS information, and demonstrates that most of the QoS requirements for telemetry data transfer can be met by using this information. This paper also addresses some topics for future investigations.

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A multiplexer / demultiplexer design suitable to a wide range of input data types and link formats is presented. Based on the Consultative Committee on Space Data Systems (CCSDS) recommendations for Packet Telemetry, the design translates the prescribed layered architecture into a modular, layered hardware implementation. The design approach minimizes hardware yielding increased reliability and decreased product cost while retaining a high degree of flexibility. This implementation can be applied to flight data acquisition (direct transmission to the ground or recorded), ground data collection (including multi-stream record systems) and inter-range communications. The use of an internationally recognized standard promotes inter-service interoperability and facilitates data handling/routing throughout a wide community.

International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / The MESSENGER mission to Mercury will downlink data files via a protocol defined by the Consultative Committee for Space Data Systems (CCSDS) called the CCSDS File Delivery Protocol (CFDP). A reduced implementation of the protocol was developed for the spacecraft due to various system constraints and operational requirements. The software operates in conjunction with the playback features of the MESSENGER flight software allowing for the autonomous downlinking of files as well as providing for the management of the file system by the mission operations team. This paper presents the software implementation, metrics, and the lessons learned.

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / This paper describes the use of an open architecture, low-cost, turnkey Telemetry, Tracking and Command (TT&C) processor system. The workstation based system was developed to satisfy the requirement for ground station equipment to handle and process multiple vehicle platforms for telemetry, command and tracking (tone or PRN), including STDN, SGLS and CCSDS link formats. The open architecture of the system allows for easy interface with external equipment for control of antenna systems, encryption units and other related station equipment. Reconfiguration for the various data formats and for system verification is done through a graphical user interfaces using operationally proven commercial-off-the-shelf (COTS) software and hardware. The open architecture of the system will allow for modifications and upgrades to be cost effective.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper introduces the Reference Architecture for Space Data Systems (RASDS) that is being developed by CCSDS. RASDS uses five Views to describe architectures of space data systems. These Views are derived from the viewpoints of the Reference Model of Open Distributed Processing (RM-ODP), but they are slightly modified from the RM-ODP viewpoints so that they can better represent the concerns of space data systems.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The United States Government, through the Integrated Program Office (IPO), currently operates a converged polar orbiting constellation of POES and DMSP satellites to acquire, process and disseminate meteorological and environmental data on a global scale. Because of the increasing need for more precise and timely meteorological data, the IPO is developing the follow on system known as the National Polar-orbiting Operational Environmental Satellite System (NPOESS). The NPOESS system is expected to use a modernized, CCSDS compatible data acquisition and distribution network, and will provide more timely data than for the current POES/DMSP satellites. The NPOESS satellite system will also continue the collection of long-term environmental data as a follow on to NASA’s Earth Observation System (EOS). The continuation of NASA’s EOS system will begin with a risk reduction effort in support of NPOESS, known as the NPOESS Preparatory Project (NPP). This paper will describe the CCSDS implementation that both the NPP and NPOESS satellites are expected to use beginning with the launch of the NPP spacecraft in 2006. The launch of the first NPOESS satellite is anticipated in 2009.

International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California / The Consultative Committee for Space Data Systems (CCSDS) is an international organization chartered to develop and adopt communications protocols and data processing standards suitable for use in space-related communication and data processing systems. Among its ongoing activities, CCSDS is in the final stages of approving recommendations for communications services and protocols to be used by "advanced orbiting systems" (AOS) typified by the international Space Station Freedom Program. As a companion activity to the development of the AOS protocols, CCSDS is in the process of defining the network management functions that are necessary to realize the full capabilities of the AOS services. CCSDS is also concerned with communicating management information among distributed network management systems, an environment that will be typical of multi-national space ventures. These network management systems are envisioned to be automated, resulting in a need for standard network management protocols and data structures. This paper briefly describes the CCSDS network management environment, and reviews the current status of CCSDS recommendations for network management functional capability, use of international standards for network management, and composition of signalling systems in support of the AOS services. The paper concludes with a timetable for future work in this area.