Service Boundaries and Domains in Software

Encoding QR Code in Software Service Boundaries and Domains

In order to support a single definition for CTI interfaces that can be applied to any boundary in a CTI system of any size, configuration, or complexity, a single key insight is required:

Regardless of the number of components in a CTI system, it can be broken down and analyzed in terms of each inter-component boundary that allows two adjacent CTI components to exchange CTI messages

In creating or integrating different CTI components, the focus at any instant is on just one intercomponent boundary through which a given component must interoperate CTI messages and the CTI interfaces that work with these messages can therefore be described in terms of a simplified CTI system which consists of just three parts: Switching domain The switching domain is everything on the logical server's side of a particular intercomponent boundary Computing domain The computing domain is everything on the logical client's side of a particular intercomponent boundary Service boundary The service boundary is the inter-component boundary that lies between the computing domain and the switching domain in a given context This simplification of a CTI system is illustrated in Figure 6-9 All interaction between a given computing domain and a switching domain takes place through a CTI service boundary

This abstraction applies to every inter-component boundary in a CTI system so care must be taken to specify what inter-component boundary is being referred to as a service boundary at any given instant Specifying the service boundary not only identifies which pair of components is being discussed, but also the CTI messages that travel between them, and the CTI interface that interprets these messages

A CTI service boundary is the inter-component boundary through which CTI messages from a CTI component acting on behalf of its computing domain are communicated to the CTI interface of a CTI component acting on behalf of the switching domain it represents In concrete terms, a service boundary can take the form of either a protocol or a programmatic interface A service boundary that lies between two software components running on the same hardware component (eg, a computer) can take the form of a programmatic interface through which CTI messages are passed using function calls Otherwise, the service boundary takes the form of a CTI protocol used for conveying CTI messages as a stream of data

The term switching domain refers to all of the telephony resources that can be observed or controlled through a designated service boundary and all of the CTI components that provide this access The mechanism a switching domain uses to interact with a computing domain through the service boundary is its CTI interface6-4 The switching domain encompasses any telephony resources associated with components in the switching domain that can be accessed using this CTI interface This is illustrated in Figure 6-10

Switching domain versus switching function CSTA phase III differs from ECTF C001 and the Versit CTI Encyclopedia by differentiating between the switching domain in which resources are manipulated and an associated switching function which the CTI interface provides access to

In concrete terms, the number and type of hardware and software components that might be found in a given switching domain is unbounded However, at least one component must contain call processing functionality Typically it will include one of the following: Switches - Front-end switches - KSUs or Hybrids - PBXs - Application specific switches Telephone station equipment - Telephone station - Telephone station peripherals Any type of component that can be found in a CTI system may be found in a switching domain given the service boundary context Other types of CTI hardware components are presented in 11 and software components are presented in 8