REAL TIME LOGIC PRAGMATIC GENERAL MULTICAST (RTPGM)
OVERVIEW
 Real Time Logic Pragmatic General Multicast (RTPGM) is RT Logic’s implementation of the PGM protocol (RFC 3208) for real-time telemetry applications. RTPGM provides a reliable, bandwidth-efficient, scalable solution for telemetry data distribution over Internet Protocol (IP) networks. PGM is plug-in compatible with standard IP network communications equipment, making it a ready, viable alternative to Transmission Control Protocol (TCP) or User Datagram Protocol (UDP). RT Logic offers RTPGM as a software product for both data source and data consumer applications. RT Logic’s high performance RTPGM software is especially designed for transporting packet based mission data or telemetry using Consultative Committee for Space Data Systems (CCSDS) constructs.

APPLICATION
 Telemetry systems are migrating away from dedicated serial to lower cost and more versatile IP-based network-centric architectures for data distribution. Most systems use either TCP/IP for guaranteed delivery or UDP for bandwidth constrained networks.

PGM combines the reliability of TCP with the bandwidth-efficient UDP for a scalable and reliable transport mechanism to reliably distribute telemetry data from multiple sources to the multiple consumers of the data. RTPGM is a natural fit for distributing and filtering CCSDS Virtual Channel Data Unit (VCDU) frames or source packets over Wide Area Networks (WANs) using a publish/subscribe paradigm.

RTPGM is ideal for hot-backup scenarios where a secondary consumer shadows the primary without requiring additional bandwidth. PGM supports the dynamic addition of consumers and can be further optimized with the addition of commercially available PGM-aware network devices.
FEATURES
Especially Designed For Telemetry Applications

Efficient Use Of Bandwidth For Data Distribution Across WAN/LAN

Scalable Data Distribution With Reliable Delivery Mechanism

Guarantees Either Reception Of All Data Or Detection Of Unrecoverable Data

RFC 3208 Compliant Implementation

Compatible With Standard Network Elements (Routers, Switches)

CCSDS VCDU And CCSDS Packet Support

 Multicast Transport With TCP Benefits
  • Duplicate Free
  • Reliable
  • Ordered
  • Efficient
PGM-Aware Network Elements Available For Increased Network Efficiency

High-Speed Data Distribution Rates To 800 Mbps

Available As Software Libraries (Linux)

Plug-and-Play Compatibility With Telemetrix Products
MODULAR, DIGITAL DESIGN
 RTPGM conforms to RFC 3208, the PGM Reliable Transport Protocol Specification. PGM operates in the transport layer of the Open Systems Interconnection (OSI) protocol stack to guarantee either the reception of all data, or the detection of unrecoverable data loss according to how the system is tuned. Data transmitted by RTPGM is duplicate free, reliable, and ordered.

RTPGM transmits only one copy of the data onto the network regardless of the number of consumers. Using a Negative Acknowledgement (NAK) handshake, RTPGM addresses network errors on an exception basis to reliably transport data to registered consumers.

The RTPGM software service for Linux is available as a standalone software product or as an add-on to the T500 product series.
RTPGM
ADVANTAGES
 RTPGM combines the best features of TCP and UDP.
SPECS
CCSDS Compatibility
  • VCDU
  • Source Packets
  • Raw Data
  • Framed Data
  • SLE (RAF, RCF, F-CLTU)
OS Compatibility
  • Linux
Performance
  • 800 Mbps Throughput Rate
  • Low Latency Contribution
Inputs/Outputs
  • 10/100/1000 Mbps Ethernet