THE IMS: IP Multimedia Concepts and Services, 3rd Edition

9

Multimedia Telephony

9.1 Introduction

We already have telephony so that we can talk to each other. We have video telephony so that we can see the other person or we can share what we see or have seen. We have messaging so that we can send instant notes, pictures, video clips etc. These can take place simultaneously but services typically use different applications in the device or bundled application is propriatery solution itself. IMS multimedia telephony service is the answer to build interoperating communication service that can provide a truly global service, in the spirit of good old telephony.

IMS multimedia telephony is a blended multimedia service suite. It allows users to establish communications between them and enrich that by enabling supplementary services. Typically it is a service using speech and speech combined with other media components, but the service is not limited to always include speech, it also caters for other media or combinations of media (e.g. text and video). IMS Multimedia Telephony service includes the following standardized media capabilities:

• full duplex speech;
• real time video (simplex, full duplex), synchronized with speech if present;
• text communication;
• file transfer;
• video clip sharing, picture sharing, audio clip sharing. Transferred files may be displayed/replayed on receiving terminal for specified file formats.

Based on these capabilities different types of communication use cases could be realized e.g. voice calls, voice call enriched ...