OSI PICS Manual

Tandem OSI PICS Manual–135046
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Introduction
This manual describes the conformance of Tandem OSI-related products to standards
published by ISO (International Organization for Standardization), CCITT (International
Telegraph and Telephone Consultative Committee), and the like. The formal description
of each Tandem product, called a PICS (protocol implementation conformance
statement), strictly follows the format specified in the applicable standard. In some
cases when a PICS does not currently exist as part of a standard, PICS are published by
national or international OSI-promotional organizations such as COS (Corporation for
Open Systems).
This section briefly describes the purpose and origin of PICS and provides an overview
of all the Tandem OSI (Open Systems Interconnection) products and their relationships
to the OSI Reference Model and to ISO standards. This section is intended to help
acquaint you with PICS and with Tandem OSI products.
The section includes the following topics:
•
What Are PICS?
•
PICS Version Information
•
Overview of Tandem OSI Products
•
Relationship of Products to OSI Reference Model
•
Standards Implemented
What Are PICS?
The following two subsections describe what PICS are and the two ways in which they
are frequently used.
PICS Definition
A PICS (protocol implementation conformance statement) is a type of document defined
by ISO 9646, which contains definitions related to conformance testing of OSI (Open
Systems Interconnection) protocols. It is used in the evaluation of the conformance of a
product to a particular standard. The PICS for each specific OSI protocol follows a
format, called a proforma, which is different for each standard. The proforma for each
ISO standard is usually included within the standard, either as an annex or addendum or
as a separate part of the standard.
Note. All PICS in this manual adhere as closely as possible to the specified proforma. Minor
changes have been made in some sentences to correct syntax and punctuation.
Note. The notation conventions established for each proforma are not consistent among all
PICS. For example, to indicate that a feature is implemented, some proformas specify an entry
of YES, others specify an entry of Y, others specify no entry at all (only non-implemented
features require an entry), and others specify an entry of I (for implemented), and so on. The
notation conventions are specified at the beginning of each PICS.