This course describes the functional components and operation of public telephony systems based on the Internet Protocol (IP) with emphasis on those employing an IP Multimedia Subsystem (IMS) in a next generation network.
This ""Voice over IP systems"" online course begins by describing how calls can be made between Voice over IP system users and customers of a public switched telephone network (PSTN).
Interworking issues discussed include the conversion between different signalling protocols, the conversion between telephone numbers and SIP addresses and the transport of PSTN signalling messages over a VoIP system.
The role of the various system components that allow interworking between a VoIP system and PSTNs are described including media gateways, signalling gateways and media gateway controllers. The role and facilities provided by the various VoIP signalling protocols are described including SIP, SIGTRAN, and H.248.
The role of an IP Multimedia Sub-system (IMS) in a next generation network is described and the function of its various functional components explained. The role and operation of an IMS-based PSTN emulation service is explained with reference to the role of access gateways and multiservice access nodes.
This course assumes that you already have an understanding of the basic principles and operation of SIP-based Voice over IP systems. It is recommended that the online course MEB: ""Voice over IP"" is studied before attempting this course.
This e-learning course has a comprehensive range of interactive training facilities to provide a total learning experience. Technical words and acronyms have links to an online glossary giving an instant explanation. Interactive simulations explain concepts and systems operation.
Onscreen question sessions at the end of each module test understanding and provide further guidance and instruction. Revision links provide quick access to subjects previously discussed and relevant to the module being studied. Once studied as a structured, assessed course, the content can be browsed for revision or reference.
By the end of this course you will be able to:
- describe the components, facilities and operation of Megaco Voice over IP systems that use the gateway control protocol as specified by the ITU recommendation H.248.
- describe the role and facilities provided by the various SIGTRAN protocols in relation to the transport of signalling messages between a circuit-switched network and a Voice over IP network.
- describe the role and facilities provided by the SIP-I and SIP-T protocols with reference to the preservation of PSTN signalling information in a VoIP system.
- describe the role of, and compare, User ENUM and Carrier ENUM services, with reference to the translation between E.164 telephone numbers and other addressing formats.
- describe the role of the functional components of an IP Multimedia Sub-system (IMS) and the associated transport control elements of a next generation network.
- describe the role and operation of a PSTN emulation service based on the use of an IMS with reference to access gateways and the access gateway control function.
- describe the role of a multi-service access node (MSAN) with reference to the integration of voice, video and Internet services to customers.
1. Course introduction
2. Megaco VoIP sub-system
3. SIGTRAN protocols
4. PSTN VoIP interworking
5. Call control in NGNs
6. IMS-based PSTN emulation