BS 6568-1:1988

National foreword
Committees responsible
Reference Model
0 Introduction
1 Scope and field of application
2 Definitions
3 Notation
4 Introduction to Open Systems Interconnection (OSI)
5 Concepts of a layered architecture
6 Introduction to the specific OSI layers
7 Detailed description of the resulting OSI
    architecture
Annexes
A Brief explanation of how the layers were chosen
B Alphabetical index to definitions
Figures
1 Open systems connected by physical media
2 Basic elements of OSI
3 Layering in co-operating open systems
4 (N + 1)-entities in the (N + 1)-layer communicate
    through the (N)-layer
5 (N)-protocols between (N)-entities
6 Communications through a relay
7 Entities, service-access-points, and identifiers
8 Hierarchical (N)-address-mapping
9 Relationships among data-units
10 An illustration of mapping between data-units in
    adjacent layers
11 Relationship between (N)-service-data-unit, (N)-
    protocol-data-unit and (N - 1)-servce-data-unit
    within a layer
12 Seven layer reference model and peer protocols
13 Communication involving relay open systems
14 Application-entity
15 Several consecutive session-connections
16 Several consecutive transport-connections
17 Association of tranport-addresses and network-
    addresses
18 Association of one network-address with several
    transport-addresses
19 Interconnection of a low quality subnetwork and a
    high quality subnetwork
20 Interconnection of an enhanced low quality
    subnetwork and a high quality subnetwork
21 Interconnection of a data-circuits within the
    Physical Layer
22 Examples of physical-connections
23 Examples of interconnection
Addendum 1. Connectionless-mode transmission
0 Introduction
1 Scope and field of application
2 Definitions
3 Notation
4 Introduction to Open Systems Interconnection (OSI)
5 Concepts of a layered architecture
6 Introduction to the specific layers of the Reference
    Model
7 Detailed description of the resulting OSI
    architectured

Establishes a framework for co-ordinating the development of existing and future standards for the interconnection of computer systems and is provided for reference by those standards. It is not a product standard nor does it specify services or protocols for Open Systems Interconnection.