nalysis of the received BIWF address of MGW2 from MSS2 (during the RAB assignment request) results in the establishment of a bearer network connection with MGW2. Creating Routing Objects and Digit Analysis in the MGW This section describes the procedure for creating routing objects and digit analyses with subdestinations and routing policy for the Nb interface with MML commands. Digit analysis is needed in the Nb interface, which connects two MGWs (MGW release 4). There are two different approaches to creating digit analysis for the Nb interface: creating (basic) digit analysis, where each destination has only one subdestination; creating digit analysis, where each destination can have more than one subdestination. Creating subdestinations for a destination and defining routing policy (the latter approach above) are optional features. Generally speaking, creating a basic digit analysis is sufficient, and it is recommended that the latter approach be used only if there is a definite need for several subdestinations and routing policy measures. The routing policy function allows the percentage call distribution (also known as load sharing) to be utilised. The percentage call distribution traffic to a destination can be distributed among two or more subdestinations in predefined proportions. Creating subdestinations for a destination and defining routing policy are optional when creating the ATM backbone in the MGW release 4 network. In general, creating basic routing and digit analysis are sufficient. Subdestinations and subdestination routing policy should be used only if there is a definite need (e.g. load sharing) for several subdestinations and routing policy measures. Digit analysis and routing are closely connected to each other. Their relationship and objects used in routing and analysis in the MGW are shown in Figure 4.36 and are further described in the following section. User Plane Detailed Planning ANALYSIS DIGITS digit analysis destination subdestinations 1...5 subdestination subdestination AAL2 route A