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IRIG 106 Chapter 28 Telemetry Standards, RCC Standard 106-17 Chapter 28, July 2017 CHAPTER 28 RF Network Management Table of Contents Acronyms ...................................................................................................................................... iii Chapter 28. RF Network Management ............................................................................... 28-1 28.1 Introduction .................................................................................................................... 28-1 28.2 RF Network Management Concepts and Definitions .................................................... 28-2 28.2.1 Data Link Layer Framing................................................................................... 28-2 28.2.2 RF Link Management ........................................................................................ 28-3 28.2.3 Epoch Structure .................................................................................................. 28-3 28.2.4 Transmission Opportunities ............................................................................... 28-3 28.2.5 Guard Time ........................................................................................................ 28-4 28.2.6 Traffic Engineering Queues ............................................................................... 28-4 28.2.7 Handoff .............................................................................................................. 28-4 28.2.8 Heartbeat ............................................................................................................ 28-4 28.2.9 RF MAC Header Addressing ............................................................................. 28-5 28.2.10 Timing ................................................................................................................ 28-5 28.2.11 Virtual TxOps .................................................................................................... 28-5 28.2.12 Independent Operation ....................................................................................... 28-5 28.3 RF Media Access Control Layer.................................................................................... 28-6 28.3.1 Epoch ................................................................................................................. 28-6 28.3.2 Media Access Control Frame Structure ............................................................. 28-8 28.3.3 RF MAC Payloads ............................................................................................. 28-8 28.3.4 Frame Check Sequence .................................................................................... 28-11 28.4 Logical Link Control Layer ......................................................................................... 28-11 28.4.1 TxOp Processing .............................................................................................. 28-12 28.4.2 Queue Management Processing ....................................................................... 28-14 28.4.3 Link Metric Processing .................................................................................... 28-15 28.4.4 Heartbeat Processing ........................................................................................ 28-15 28.5 Tunnel Management .................................................................................................... 28-16 28.5.1 Tunnel Connection ........................................................................................... 28-17 28.5.2 TSS Interface Initialization .............................................................................. 28-17 28.5.3 Tunnel Operation ............................................................................................. 28-18 28.5.4 Tunnel Selection .............................................................................................. 28-18 Appendix 28-A. Documentation of TunTap Device Driver for Linux .............................. A-1 Appendix 28-B. Documentation of TunTap Project for macOS ........................................ B-1 i Telemetry Standards, RCC Standard 106-17 Chapter 28, July 2017 Appendix 28-C. Citations ...................................................................................................... C-1 List of Figures Figure 28-1. OSI Model as Related to the TmNS RF Network.............................................. 28-1 Figure 28-2. Data Link Layer Framing Overview .................................................................. 28-3 Figure 28-3. Typical Epoch Structure .................................................................................... 28-6 Figure 28-4. MSDU Insertion into RF MAC Frame .............................................................. 28-9 Figure 28-5. Fragmentation/Packing Sub-Header ................................................................ 28-10 Figure 28-6. Notional Diagram of RF MAC Frame Containing Two MSDU_Blocks ........ 28-11 List of Tables Table 28-1. RF MAC Header Vendor IDs ............................................................................ 28-5 Table 28-2. Definition of Fields in Fragmentation/Packing Sub-Header ............................. 28-9 Table 28-3. Default Interface Values for TSS Interface of Transceivers ............................ 28-17 ii Telemetry Standards, RCC Standard 106-17 Chapter 28, July 2017 Acronyms AES Advanced Encryption Standard BSN block sequence number CCMP Counter with Cipher Block Chaining Message Authentication Code mode Protocol FCS frame check sequence FPSH fragmentation/packing sub-header GPS Global Positioning System IETF Internet Engineering Task Force IP Internet Protocol LLC logical link control MAC media access control MDL Metadata Description Language ms millisecond MSDU MAC service data unit OSI Open Systems Interconnection QoS Quality of Service RF radio frequency RFC Request for Comment SDU service data unit TCP Transmission Control Protocol TE Traffic Engineering TLV Type Length Value TmNS Telemetry Network Standard TSS TmNS Source Selector TxOp transmission opportunity UDP User Datagram Protocol iii Telemetry Standards, RCC Standard 106-17 Chapter 28, July 2017 This page intentionally left blank. iv Telemetry Standards, RCC Standard 106-17 Chapter 28, July 2017 CHAPTER 28 RF Network Management 28.1 Introduction This chapter defines the mechanisms and processes for managing radio frequency (RF) links with the RF network. The RF network implements an Open Systems Interconnection (OSI) model approach (Figure 28-1) to data transmission, where data moves through the OSI stack from the application layer to the physical layer, from physical layer to physical layer through some transmission medium, then back up the stack to another application on the receiving side. For the most part, the RF network operates just like any other Transmission Control Protocol (TCP)/Internet Protocol (IP) network, where a message is created using a standard data management protocol, such as Simple Network Management Protocol; is encapsulated at the transport layer to TCP or User Datagram Protocol (UDP); and then is further encapsulated into an IP packet that contains the logical addressing and path routing determination. Where the RF network differs from the standard OSI model is in the data link and physical layers, where media access controls (MACs) have been modified to support transmission over RF links. OSI Model Layer Data Unit Function Examples High Level APIs, including resource sharing, remote file 7. Application HTTP, FTP, SNMP, SSH, TELNET access, directory services and virtual terminals Translation of data between a networking service and 6. Presentation Data an application, including character encoding, data HTML, CSS, GIF Host compression and encryption/decryption Layers Managing communications sessions, i.e. continuous 5. Session exchange of information in the form of multiple back- RPC, PAP, SSL, SQL and-forth transmissions between two nodes Managing communications sessions, i.e. continuous 4. Transport Segments/Datagram exchange of information in the form of multiple back- TCP, UDP, NETBEUI and-forth transmissions between two nodes Structuring and managing a multi-node network, 3. Network Packet IPv4 IPv6, IPSec, Apple Talk, ICMP including addressing, routing and traffic control Covered Media Reliable transmission of data frames between two 2. Data Link Frame PPP, IEE 802.2 L2TP, MAC, LLDP by this Layers nodes connected by a physical layer chapter Transmission and reception of raw bit streams over a IRIG 106 1. Physical Bit Ethernet physical layer, DSL USB, ISDN, DOCSIS physical medium Chapter 27 Figure 28-1. OSI Model as Related to the Telemetry Network Standard (TmNS) RF Network The RF network manages communications at the data link and physical layers of the OSI model. This chapter focuses on the RF network with respect to managing the data link layer of the OSI model. The RF network is a multi-node network with a network layer control and data plane. The control plane for managing the RF link layer multiple access is described in this document. For information on the physical layer of the RF network, refer to Chapter 27. The RF network’s control plane uses the existing ground network and adds RF connectivity to allow changes to RF transmission and capacity allocation in transceivers during missions. Radios need not establish direct bidirectional links with other transceivers in order to be part of the RF network. Rather, they are part of
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