Evaluating and refining call setup delay

The speech service call establishment procedure uses a combination of signalling protocols. This paper describes the messages associated with these signalling protocols and identifies the relationship between them. RNC databuild parameters related to call setup are identified and discussed. A set of measurements are used to illustrate the dominant phases of speech call establishment. The dominant phases are discussed in terms of reducing call setup delay while minimising the impact upon other aspects of system design. The paper concludes by suggesting a number of ways in which call set-up delay can be refined.