ITU-T Study Group 17 works on security related issues.
In the technical Flyer, the building block are listed as
- Security Architecture and Frameworks
- Telecommunication Security
- Security in Frame Relay
- Security Techniques
- Directory Services and Authentication
- Network Management Security
- Systems Management
- Televisions and Cable Systems
- Multimedia Communications
- Message Handling Systems (MHS)
By looking the standards on the ones with “bold” gives a good overview. Another good overview is provided by their “Security Manual” from 2009 called “Security in telecommunications and information technology – An overview of issues and the deployment of existing ITU-T Recommendations for secure telecommunications”. It is available in different languages.
There is many other good collection on information, like