One way to deal with the tough requirements of packetized voice gateway designs is to use a DSP core-based implementation. Using a DSP core allows the designer to tightly integrate peripherals and accelerators for processing the plethora of algorithms in a VoIP application. In recent years, the combined influence of technology and business forces in the communication industry has had an unprecedented impact on network infrastructures, from the core to the customer premise equipment. New problems to solve To reap the advantages of reduced cost and the bandwidth savings of carrying voice communications over packet networks, designers must deal with problems that did not exist in traditional telephone networks, such as much longer network delays, echoes, and lost voice packets. Delay in VoIP applications manifests as a combination of network and speech-processing delays.
Network delay is a function of the capacity of the network and the speed of the packet processing.
This delay can be as high as 70 ms in some IP networks. Echo becomes a significant problem when the round-trip delay becomes greater than 50 ms. VoIP systems address this problem by implementing echo-cancellation algorithms. IP networks, however, may drop data frames. VoIP system architecture VoIP systems carry voice and signaling information that is required to interface telephony equipment to a packet network.