.xxx Table X-3: Select X Series Recommendations (continued) Recommendation Description X.500 Information technology — Open Systems Interconnection (OSI) - The Directory: Overview of concepts, models and services X.601 Multi-peer communications framework X.700 Management framework for Open Systems Interconnection (OSI) for CCITT applications X.800 Security architecture for Open Systems Interconnection for CCITT applications X.901 Information technology - Open Distributed Processing - Reference Model: Overview |