introdution,advantages and disadvantages features , some photos, conclusion use in computer field

Voice / data integration is important to the network designers of both service providers and the company. Service providers are attracted to the lowest cost model - the cost of packet voice is currently estimated at between 20 and 50 percent of the cost of a traditional circuit-based voice network. Similarly, business network designers are interested in direct cost savings associated with by-pass and tandem switching. Both are also interested in so-called "soft savings" associated with reduced maintenance costs and more efficient network management and control. Finally, packet-based voice systems offer access to recently improved services, such as unified messaging and application control. These, in turn, promise to increase the productivity of users and differentiate services.

The integration of voice and data technologies has accelerated rapidly in recent years due to the interactions between supply and demand. On the demand side, customers are leveraging investment in network infrastructure to leverage integrated applications as voice applications. On the supply side, providers have been able to take advantage of advances in many areas, including standards, technology and network performance.