Communications networks are rapidly evolving into policy-based, packet-oriented networks designed to provide a particular quality-of-services (QoS) for subscribers while reducing the costs associated with capital expansions, network operations, and management. If you are involved with telecommunications planning, engineering, deployment, strategy, marketing, or services creation, it is critical that you understand the technology and business implications of IMS.

Susie had been using Instant Messaging (IM) with her wireless carrier for eight months when she decided to add Push To Talk (PTT) as well. While she was quite happy with the first service, and had heard many good things about the second service from her friend, she was not at all satisfied with how the two services worked together—or rather didn’t work together.