BS ISO/IEC 8473-1:1998

1 Scope
2 Normative references
    2.1 Identical Recommendations/International
          standards
    2.2 Paired Recommendations/International standards
          equivalent in technical content
    2.3 Additional references
3 Definitions
    3.1 Reference model definitions
    3.2 Service conventions definitions
    3.3 Network layer architecture definitions
    3.4 Network layer addressing definitions
    3.5 Local area network definitions
    3.6 PICS definitions
    3.7 Additional definitions
4 Abbreviations
    4.1 Data units
    4.2 Protocol data units
    4.3 Protocol data unit fields
    4.4 Parameters
    4.5 Miscellaneous
5 Overview of the protocol
    5.1 Internal organization of the Network layer
    5.2 Subsets of the protocol
    5.3 Addresses and titles
    5.4 Service provided by the protocol
    5.5 Underlying service assumed by the protocol
6 Protocol functions
    6.1 PDU composition function
    6.2 PDU decomposition function
    6.3 Header format analysis function
    6.4 PDU lifetime control function
    6.5 Route PDU function
    6.6 Forward PDU function
    6.7 Segmentation function
    6.8 Reassembly function
    6.9 Discard PDU function
    6.10 Error reporting function
    6.11 PDU header error detection function
    6.12 Padding function
    6.13 Security function
    6.14 Source routeing function
    6.15 Record route function
    6.16 Quality of service maintenance function
    6.17 Priority function
    6.18 Congestion notification function
    6.19 Echo request function
    6.20 Echo response function
    6.21 Scope control function
    6.22 Classification of functions
7 Structure and encoding of PDUs
    7.1 Structure
    7.2 Fixed part
    7.3 Address part
    7.4 Segmentation part
    7.5 Options part
    7.6 Data part
    7.7 Data PDU
    7.8 Inactive Network layer protocol
    7.9 Error Report PDU
    7.10 Echo Request PDU
    7.11 Echo Response PDU
    7.12 Multicast Data PDU
8 Provision of the underlying service
    8.1 Subnetwork points of attachment
    8.2 Subnetwork quality of service
    8.3 Subnetwork user data
    8.4 Subnetwork dependent convergence functions
9 Conformance
    9.1 Static conformance
    9.2 Dynamic conformance
    9.3 PICS proforma
Annex A PICS proforma
    A.1 Introduction
    A.2 Abbreviations and special symbols
    A.3 Instructions for completing the PICS proforma
    A.4 Identification
    A.5 Major capabilities
    A.6 End systems
    A.7 Intermediate systems
Annex B Supporting technical material
    B.1 Data unit lifetime
    B.2 Reassembly lifetime control
    B.3 The power of the header error detection function
Annex C Algorithms for PDU header error detection function
    C.1 Symbols used in algorithms
    C.2 Arithmetic conventions
    C.3 Algorithm for generating checksum parameters
    C.4 Algorithm for checking checksum parameters
    C.5 Algorithm to adjust the checksum parameter when an
          octet is altered

Defines a protocol for providing the connectionless-mode Network service described in ITU-T X.213, and for performance of certain Network layer management functions.

This Recommendation | International Standard specifies a protocol that is used to provide the connectionless-mode Network service described in ITU-T Rec. X.213 | ISO/IEC8348 and to perform certain Network layer management functions. The protocol relies upon the provision of an underlying connectionless-mode service by real subnetworks and/or data links. The underlying connectionless-mode service assumed by the protocol may be obtained either directly, from a connectionless-mode real subnetwork, or indirectly, through the operation of an appropriate Subnetwork Dependent Convergence Function (SNDCF) or Protocol (SNDCP) over a connection-mode real subnetwork, as described in ISO/IEC8648. This Recommendation | International Standard specifies the operation of the protocol with respect to a uniform, abstract \'underlying subnetwork service\'. Other Recommendations | International Standards specify the way in which this \'underlying subnetwork service\' is obtained from real subnetworks, such as those which conform to ISO/IEC8802 or ISO/IEC8208. The \'underlying subnetwork service\' may be obtained from real subnetworks other than those that are specifically covered by the other Recommendations | International Standards. This Recommendation | International Standard specifies: procedures for the connectionless transmission of data and control information from one Network entity to one or more peer Network entities; the encoding of the Protocol Data Units (PDUs) used for the transmission of data and control information, comprising a variable-length protocol header format; procedures for the correct interpretation of protocol control information; and the functional requirements for implementations claiming conformance to this Recommendation | International Standard. The procedures are defined in terms of: the interactions among peer Network entities through the exchange of protocol data units; the interactions between a Network entity and a Network service user through the exchange of Network service primitives; and the interactions between a Network entity and an abstract underlying service provider through the exchange of service primitives. This Recommendation | International Standard also provides the PICS proforma for this protocol, in compliance with the relevant requirements, and in accordance with the relevant guidance, given in ITU-T Rec. X.290 | ISO/IEC9646-1.