Technology - Infrastructure - Networks 2 - SS7 PABXs Centrex CTI Number Portability

Synopsis

Signalling System 7 is the protocol by which most telephone exchanges communicate and set up calls. This report discusses SS7 and the older MFC/R2 signalling protocols, - ISDN and POTS calls, CLASS services, and Centrex PABX emulation across multiple sites, including with the Asterisk open-source server-based system. Also discussed are PABXs, ‘key systems’, Computer Telephony Integration (CTI) and Number Portability (NP).

Table of Contents

• 1. Synopsis
• 2. Signalling System No. 7 (SS7)
  • 2.1 MFC/R2
  • 2.2 SS7 network structure
    • 2.2.1 Signal Switching Point (SSP)
    • 2.2.2 Signal Transfer Point (STP)
    • 2.2.3 Signal Control Point (SCP)
  • 2.3 SS7 packets and addressing
  • 2.4 Call establishment messages
  • 2.5 SS7 is antiquated
  • 2.6 Higher level SS7 applications
  • 2.7 ISDN and SS7
• 3. The Intelligent Network
• 4. CLASS services
  • 4.1 Calling Number Display – Caller ID
  • 4.2 Caller ID spoofing
• 5. PABXs and key systems
  • 5.1 VoIP PABXs
  • 5.2 Asterisk and Trixbox
• 6. Payphones
• 7. Centrex Services
• 8. Computer Telephony Integration (CTI)
  • 8.1 CTI applications
  • 8.2 CTI standards
• 9. Number portability (NP)
  • 9.1 The ‘Simple Intelligent Network’ solution
  • 9.2 Assigning the costs of portability
• 10. Related reports

• Exhibit 1 – CLASS Services