SS7 (Signaling System 7)

SS7 is a critical signaling protocol used in Public Switched Telephone Networks (PSTN) and early mobile networks. Despite its age, it remains an essential component in many telecommunications systems worldwide, making its security a top priority for telecom operators.

SS7 Overview
Key characteristics and uses of the SS7 protocol
  • Primarily used in 2G/3G networks and PSTN interconnection
  • Supports essential services like call setup, SMS, and roaming
  • Consists of various sub-protocols (MTP, SCCP, TCAP, MAP, etc.)
  • Operates on a separate signaling network, distinct from voice channels
  • Enables intelligent network services and number portability
  • Vulnerable to attacks due to lack of built-in security measures
Best Practices for SS7 Security
  1. Implement comprehensive SS7 firewall solutions
  2. Regularly update and patch all SS7 network elements
  3. Conduct periodic security assessments and penetration testing
  4. Train staff on SS7 security risks and mitigation strategies
  5. Participate in industry threat intelligence sharing programs
  6. Implement strong access controls and authentication for SS7 network management
  7. Monitor international SS7 traffic for anomalies
  8. Develop and maintain an incident response plan specific to SS7 attacks
  9. Implement end-to-end encryption for sensitive signaling messages where possible
  10. Regularly review and update security policies and procedures
  11. Conduct thorough risk assessments before interconnecting with new partners
  12. Implement network segmentation to isolate critical SS7 infrastructure
  13. Use virtual private networks (VPNs) for secure remote access to SS7 systems
  14. Implement robust logging and auditing mechanisms for all SS7 transactions
  15. Develop a roadmap for transitioning to more secure signaling protocols