ARINC 637 : 1993

1.0 INTRODUCTION
1.1 Purpose
1.2 Scope
1.3 Background
1.4 Network Layer Model Overview
1.4.1 Subnetwork Access
1.4.2 Subnetwork Dependent Convergent Function (SNDCF)
1.4.3 Subnetwork Independent Convergence Protocol
              (SNICP) Sublayer
1.5 Document Overview
1.5.1 NSAP Addressing Plan
1.5.2 Internetworking
1.5.3 Routing Information Exchange
1.5.4 Network Layer Management Information Base (MIB)
1.5.5 Avionics and Air-Ground SNDCF
1.6 Relationship of this Document to Other Standards
1.6.1 Relationship of this Document to ARINC
              Characteristics and Specifications
1.6.2 Relationship to Other Standards
1.7 Regulatory Approval
1.8 Documents Referenced
FIGURES
1.6.2-1 Relationship of Standards
2.0 INTERNETWORK ADDRESSING
2.1 Network Service Access Points and Network Entity
              Titles
2.2 ATN Network Addressing Information
2.2.1 ATN NSAP Addressing
2.2.1.1 Initial Domain Part (IDP)
2.2.1.1.1 Authority and Format Identifier (AFI)
2.2.1.1.2 Initial Domain Indicator (IDI)
2.2.1.2 Domain Specific Part (DSP)
2.2.1.2.1 Version (VER)
2.2.1.2.2 Administrative Identifier (ADM)
2.2.1.2.3 Routing Domain Format (RDF)
2.2.1.2.4 Area Routing Selector (ARS)
2.2.1.2.5 Location Identifier (LOC)
2.2.1.2.6 System Identifier (SYS)
2.2.1.3 Selector Value (SEL)
3.0 INTERNETWORKING SERVICE AND PROTOCOL
3.1 Introduction
3.1.1 Model
3.1.2 General Operation
3.2 Services
3.2.1 Services Provided by the Internetwork Protocol
3.2.1.1 Network UNITDATA Request
3.2.1.2 Network UNITDATA Indication
3.2.1.3 Network Echo Request
3.2.1.4 Network Echo Indication
3.2.2 Underlying Service Assumed by the Internetwork
              Protocol
3.2.2.1 Subnetwork UNITDATA Request
3.2.2.2 Subnetwork UNITDATA Indication
3.2.2.3 Subnetwork Facility Request
3.2.2.4 Subnetwork Facility Indication
3.2.2.5 Subnetwork Report Indication
3.2.3 Services Assumed from the Local Environment
3.2.3.1 S-TIMER Request
3.2.3.2 S-TIMER Response
3.2.3.3 S-TIMER Cancel
3.3 Specifications of the Internetwork Protocol
3.3.1 Protocol Functions
3.3.1.1 NPDU Composition Function
3.3.1.2 NPDU Decomposition Function
3.3.1.3 Header Format Analysis Function
3.3.1.4 NPDU Lifetime Control Function
3.3.1.5 Route NPDU Function
3.3.1.6 Forward NPDU Function
3.3.1.7 Segmentation Function
3.3.1.8 Reassembly Function
3.3.1.9 Discard PDU Function
3.3.1.10 Error Reporting Function
3.3.1.11 PDU Header Error Detection Function
3.3.1.12 Padding Function
3.3.1.13 Security Function
3.3.1.14 Source Routing Function
3.3.1.15 Record Route Function
3.3.1.16 QOS Maintenance Function
3.3.1.17 Priority Function
3.3.1.18 Congestion Notification Function
3.3.1.19 Echo Function
3.3.2 NPDU Structure and Format
3.3.2.1 General NPDU Structure
3.3.2.2 NPDU Header Fixed Part
3.3.2.2.1 Network Layer Protocol Identifier
3.3.2.2.2 Header Length Indicator
3.3.2.2.3 Version/Protocol Identifier Extension
3.3.2.2.4 NPDU Lifetime
3.3.2.2.5 Segmentation Permitted Flag
3.3.2.2.6 More Segments Flag
3.3.2.2.7 Error Report Flag
3.3.2.2.8 Type Code
3.3.2.2.9 NPDU Segment Length
3.3.2.2.10 NPDU Header Checksum
3.3.2.3 NPDU Header Address Part
3.3.2.4 NPDU Head Segmentation Part
3.3.2.4.1 Data Unit Identifier
3.3.2.4.2 Segment Offset
3.3.2.4.3 NPDU Total Length
3.3.2.5 NPDU Header Options Part
3.3.2.5.1 Padding
3.3.2.5.2 Security
3.3.2.5.3 Source Routing
3.3.2.5.4 Record Route
3.3.2.5.5 Quality of Service Maintenance Option
3.3.2.5.6 Priority
3.3.2.6 NPDU Data Part
3.3.2.7 Data NPDU
3.3.2.8 Error Report NPDU
3.3.2.8.1 Reason For Discard
3.3.2.8.2 Error Report Data Part
3.3.2.9 Echo Request NPDU
3.3.2.10 Echo Reply NPDU
4.0 ES-IS PROTOCOL SPECIFICATION
4.1 Introduction
4.2 Role of ISO 9542
4.3. ISO 9542 Service Definition
4.3.1 Initiating ISO 9542 over Air/Ground Subnetworks
4.3.2 Initiating ISO 9542 over Avionics Subnetworks
4.4 ISO 9542 Protocol Functions and PDU Structure
4.4.1 Protocol Functions
4.4.2 PDU Structure
4.4.2.1 Fixed Header
4.4.2.2 ESH PDU Parameters and Options
4.4.2.3 ISH PDU Parameters and Options
4.4.2.4 RD PDU Parameters and Options
4.5 Air-ground Subnetwork PDU Requirements
4.6 Avionics Subnetwork PDU Requirements
4.7 Summary of PDU Types and Options
4.8 Recommended Implementation Provisions
FIGURES
4.7 PDU Options
5.0 INTER-DOMAIN ROUTING PROTOCOL
5.1 Introduction
5.2 Inter-Domain Addressing
5.3 IDRP Protocol Elements
5.3.1 Structure and Content of BISPDUs
5.3.2 KEEPALIVE PDU
5.4 Network Dependent Functions
5.4.1 Connection-Event.indication
5.4.2 Disconnect-Event.indication
5.4.3 IN-Event.indication
5.4.4 OUT-Event.indication
5.5 Policy Information Base
5.5.1 Path Selection
5.5.1.1 Policies and IDRP Distinguishing Attributes
5.5.1.2 Use of Priority
5.5.1.3 Use of Transit Delay
5.5.1.4 Use of Capacity
5.5.1.5 Use of Expense
5.5.1.6 Use of Traffic Type
5.5.1.7 Default
5.5.1.8 Subnetwork Preference
5.5.1.8.1 Use of NEXT_HOP Attribute in UPDATE PDUs
5.5.1.9 Coordination Between IDRP Policies and Subnetwork
              Connectivity Policies
5.5.1.10 Coordination of Policies
5.5.2 Minimizing Aircraft Mobility Advertisement and
              Dissemination
5.5.2.1 Path Advertisement
5.5.3 Distribution Lists
5.5.4 Route Aggregation
6.0 SUBNETWORK DEPENDENT CONVERGENCE
6.1 Introduction
6.1.1 CLNS to CONS Convergence
6.1.2 CLNS Header Compression
6.1.2.1 Additional Header for Derived NPDU
6.1.3 SATCOM-Specific Subnetwork Dependent Convergence
6.1.4 AVPAC-Specific Subnetwork Dependent Convergence
6.1.5 Mode-S Specific Subnetwork Dependent Convergence
6.1.6 HF Specific Subnetwork Dependent Convergence
6.1.7 Gatelink
6.2 Air-Ground SNDC Facilities and Services
6.2.1 Facility for Conveying Service Characteristics
6.2.2 Air-Ground Mobile Subnetwork Service Provisions
6.2.3 Mobile SNDCF Protocol Identifiers
6.2.4 Mobile SNDPDU Formats for ISO 8473 IP
6.3 Avionics SNDCF
6.3.1 Avionics ARINC 429 Link Layer
6.3.1.1 ARINC 429 Connectionless-mode Data Link Service
6.3.1.2 ARINC 429 Connectionless-mode Data Link Protocol
6.3.2 Avionics OLAN
6.3.2.1 Avionics OLAN Service
6.3.2.2 Avionics OLAN Protocol
6.3.2.3 Ethernet LAN (ELAN)
ATTACHMENTS
1 Protocol Organization
2 Internetwork Layer
3 Internetwork Service
4 ES-IS Protocols
5 IDRP Format Tables
6 Queue Length Averaging Algorithm
APPENDICES
A Network Layer Management Information Base
B System Identifier Guidelines
C Glossary
D Routing Initiation Events

Provides general and specific design guidance for the installation and development of the Network layer protocols and services need to route and relay bit-oriented air-ground data link messages in an Open Systems Interconnection (OSI) environment. Describes the communication functions that should be performed by the aircraft avionics to sucessfully transfer messages using standard OSI protocols.