X.25 Access Network Configurator Tool (X25-ANC)

The X25-ANC Tool is used in the GSAC DSS application which takes the technical specification of a service (e.g., communication, processing and usage requirements) and suggests the most appropriate⁽¹⁾ network and service resource assignments (configurations) to support the service.

The X.25-ANC Tool is rule-based software which aids the user in generating a set of feasible X.25 Access Network configurations that can be installed to support a customer's request for a service. In doing so it provides support in the tasks which must be undertaken to configure X.25 access. These tasks are :

• Determine Feasibility of the implementation of each requirement on an X.25 network. This task checks the suitability of the service for X.25 and also checks for the feasibility of the service at the local node.
• Dimensioning the requirements. In this task support is provided in determining the bandwidth which should be supplied to the customer to meet the required quality factors. Dimensioning is accomplished using the Erlang B and M/M/1 queuing models.
• Configure. Here the user is presented with a choice of configuration steps which may be done.

These are :

• Check Existing Configuration determines whether the service can be accommodated on the customers existing configuration¹ given the bandwidth requirements determined in the dimensioning step,
• Configure Service Access Controller (SAC),
• Configure Access Link. (AL),
• Configure AN/TN Interface (ATI),
• Aggregate Configurations. Each X.25 Access Network Configuration contains a SAC, AL and ATI configuration. This task takes all the SAC, AL and ATI configurations and determines which of each it can combine in order to make up an overall X.25 Access Configuration. An example of such a configuration is shown in Fig. 1.
• Evaluate takes the set of configurations and ranks tham according to Service Provider criteria.
• Accept Configuration accepts the chosen configuration , writes the results and exits the tool.

Fig. 1 - Example X.25 Access Network Configuration.

This diagram shows the steps taken in the X.25-ANC to determine a X.25 solution for the Access Network.

Note 1: e.g. a choice of criteria to determine appropriateness at runtime is possible (for GSAC). Note 2: If the customer already has X.25 capabilities.