562 Private networking with DPNSSN0008589 3.3Guidelines for creating a private numbering plan with DPNSSUse the following guidelines when creating a private numbering plan with DPNSS.• When creating HLCs for the nodes in your system, avoid numbering conflicts betweennetwork nodes and internal DNs, Hunt group DNs.• Program a Private Access Code into your destination routing tables to avoid conflicts withyour internal HLC and dest code numbering plan. For example, if a dialout HLC is 848, butthis number already exists in the Business Communications Manager system for an extension,the routing tables should add a Private Access Code to the dest code. If the code isprogrammed as 6, the dest code becomes 6848. 6848 uses a route to dial out 848 using theDPNSS line pool, allowing the call to be placed.Note that a Private Access Code is required only for specific DPNSS features such asDiversion, Route Optimization, and Redirection.Customizing the DPNSS routing serviceYou can customize the routing service using the following restrictions:• Direct Inward Access (DIA) lines allow incoming calls on private circuits to be directed totelephones without going through the normal call reception. Each DIA line is assigned to oneor more extensions and is given a distinct Private Received number. When someone onanother system on the network dials the Private Received number on a DPNSS line, theBusiness Communications Manager system checks all received digits, compares the digits toan internal table and routes the call to the appropriate DIA line. All extensions programmed tohave access to that DIA line will then alert for the incoming call.• Dialing restrictions can be added to lines in line pools. Filters can restrict the use of the line tospecific area codes.• You can use host system signaling codes as part of the dial out for a route. Routing can also beused as an alternate method for a direct-dial digit. For example, create a destination code 0 andprogram the number of the internal or external destination as the dial out. Digit absorptionshould be set to 1. Because overflow routing directs calls using alternate line pools, a call maybe affected by different line restrictions when it is handled by overflow routing.
