Foreword
Introduction
1 Scope
2 Normative references
3 Definitions
4 Abbreviations
5 Overview
6 Network connection establishment phase
7 Network connection release phase
8 Data transfer phase - Data transfer service
9 Data transfer phase - Receipt confirmation service
10 Data transfer phase - Expedited data transfer
   service
11 Data transfer phase - Reset service
12 Response to protocol violations
13 Conformance
Annex A (normative) - X.25 (1980) Subnetwork Dependent
        Convergence Protocol
Annex B (normative) - Classification
Annex C (normative) - Subnetwork Convergence Protocol
        for Use With X.25 Permanent Virtual Circuits
Annex D (normative) - Protocol Implementation
        Conformance Statement Proforma
Annex F (informative) - Use of X.25/PLP NPAI
Annex G (informative) - Transit Delay Calculations
Annex H (informative) - Example of Priority Negotiation
Annex I (informative) - Differences between Recommendation
        X.223 and ISO/IEC 8878