Telecom Module 3
Length: 90 minutes
Time: 14.15-15.45

Moscow only

Module title:
Multi-point VoIP Conferencing – design and development

Target audience:
DSP engineers, DSP project managers, developing VoIP conferencing products including gateways, collaborations suites, bridges, etc.

Nikolay Abkairov, SPIRIT

Module agenda


The IP telephony is the field where two technologies interact - DSP and packet networking. That requires extensive knowledge in both fields from engineers.
We start with general overview of architecture of VoIP systems, both end user and gateways, the interaction of components and logical layers. Then we discuss what algorithms are required to implement VoIP system, we briefly consider VoIP protocols and signal processing tasks. We discuss how the software should be separated into parts running on DSP and GPP. Then we proceed to questions of HW design of VoIP systems keeping in mind this separation. The examples of real-world deployments are provided.
Then we consider the problem of arranging the multipoint conference in VoIP environment. The special impact is on conferencing in non-heterogeneous networks, i.e. one having dial-up users. Ways to avoid transcoding during centralized-mixing will also be discussed.

Module agenda:

  • Overview of IP telephony, current state, trends and problems
  • VoIP system architecture
  • Separation of DSP and GPP tasks

  • GPP - ARM, Intel PC processors (PCI), networking interface

  • DSP, analog and digiatal signal interfaces (TDM buses, SLICs, DAAs)

  • GPP - DSP interaction (HPI)

  • Examples of HW design

  • Approaches to IP conferencing: server-based and server less
  • IP conferencing issues: selection of active speakers, transcoding , synchronization
  • PC based conferencing
  • DSP based conferencing

Speaker information:

Nikolay Abkairov, SPIRIT CTO
Nikolay Abkairov - SPIRIT’s CTO, is one of the most talented people in the company, who stands behind all major corporate projects, such as joint Texas Instruments – SPIRIT’s Client Side Telephony project.
Nikolay’s deep and extensive expertise in software development, science and project management field, allowed him in his late twenties to achieve excellent results in product development as well as in people management.
As a talented lead developer Nikolay regularly holds workshops and lectures for key people in DSP industry around the world.