This chapter discusses the gateway protocols that Cisco CallManager uses to communicate with Cisco gateway and trunk devices.
The primary purpose of station devices is to provide telephony services to individuals, and the primary purpose of gateway devices is to connect telephony networks to each other. CallManager uses gateway devices to allow IP telephony users to connect to non-IP-enabled telephony networks such as the Public Switched Telephone Network (PSTN) or on legacy circuit-switched Private Branch Exchanges (PBX).
CallManager also uses IP-to-IP trunking to connect members in one CallManager cluster to other voice over IP (VoIP) networks. In addition, IP trunking is used to connect one CallManager cluster to another CallManager cluster when an enterprise deploys multiple clusters for scalability, geographical, or administrative reasons.
Because CallManager supports a variety of circuit-switched and VoIP protocols, one function it can serve in your network is as a protocol translator, to connect gateways that support different call signaling protocols.
This chapter includes the following sections:
Appendix C, "Protocol Details," provides detailed information for H.323, QSIG, and SIP signaling protocols. After reviewing this chapter, refer to Appendix C for additional, related information.
Cisco CallManager Architecture
Manageability and Monitoring
Call Detail Records
Appendix A. Feature List
Appendix B. Cisco Integrated Solutions
Appendix C. Protocol Details