Range Tree Directory Number Screening for Digital Switches
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing directory number (DN) screening methods in digital switches face performance bottlenecks due to high processing overhead and memory requirements, particularly during peak traffic, as they rely on database queries or prefix pattern matches that are not scalable and resource-intensive.
Innovation Solution
A range tree-based method for DN screening, where a compact range tree is created and stored in memory to quickly determine if a directory number falls within an allowed set of numerical ranges by traversing the tree based on digit analysis, using a root node and child nodes to represent numerical bounds, allowing for efficient and scalable DN screening.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If database query approach is used for DN screening, then ease of implementation is improved, but processing overhead increases significantly
Solution Approach 1:
The patent pre-processes the directory number range information into a compact range tree structure during system initialization or maintenance periods. This preliminary action transforms the raw database into an optimized lookup structure, so that during peak traffic operations, the switch can perform fast tree traversals instead of database queries, resolving the contradiction between ease of implementation and processing overhead
Solution Approach 2:
The patent creates a simplified copy of the directory number information in the form of a range tree with numerical bounds, rather than storing and querying the full database. This copy contains only the essential range boundary information needed for screening, dramatically reducing the data size and query complexity while maintaining screening accuracy
2Speed
If prefix pattern match approach is used, then processing speed is improved for single prefixes, but memory requirements increase significantly
Solution Approach 1:
The patent merges multiple prefix patterns into a unified range tree structure that represents contiguous blocks of directory numbers using numerical lower and upper bounds. Instead of storing each prefix separately, the tree consolidates ranges (e.g., 214.222.2000-214.222.2999, 214.222.3000-214.222.3999) into a compact format that requires minimal memory while enabling fast traversal for screening
3Speed
If parse tree is used to store prefixes, then lookup speed is improved, but maintenance overhead increases significantly
Solution Approach 1:
The patent changes the structural parameters of the tree from a traditional parse tree storing individual prefixes to a range tree storing numerical lower and upper bounds. This parameter change simplifies the maintenance operations, as adding or removing directory number blocks becomes a matter of inserting or deleting range boundaries rather than traversing and modifying complex tree structures, thereby reducing maintenance overhead while preserving lookup speed
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Methods, systems, and computer program products for performing range-based directory number (DN) screening are disclosed. According to one aspect, the subject matter described herein includes a method for determining that a telecommunications device DN is within an allowed set of numerical ranges. The method includes creating a range tree for representing an allowed set of numerical DN ranges, wherein each range is defined by a numerical upper and lower bound, and storing the range tree in a memory device; receiving a telecommunications device DN to be analyzed; traversing the range tree from a root node of the tree, based on analyzing each digit of the DN, until a leaf node is reached; and determining, based on an attribute associated with the leaf node reached, whether the DN is within the allowed set of ranges.