Application Server Signaling Path Removal

Solution Overview

Problem

Conventional VoIP networks experience inefficiencies due to excessive signaling requirements, leading to increased post-dial delay (PDD) and network resource utilization, as they lack the dedicated signaling paths of traditional PSTN networks.

Innovation Solution

A network node, such as an application server, dynamically removes itself from the signaling path once it determines it is no longer necessary, using signaling protocol messages to free up resources and speed up call setup, thereby reducing PDD.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an application server remains in the signaling path throughout call setup, then call feature processing can be provided, but post-dial delay increases and network resources are unnecessarily consumed

Engineering Contradiction:

Improvecall feature processingVSAvoidpost-dial delay

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The application server extracts itself from the signaling path after completing its call feature processing function. The server removes itself by sending a REFER message to redirect the signaling flow, thereby eliminating unnecessary signaling delays while maintaining the reliability of call feature processing.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The application server dynamically adjusts its presence in the signaling path based on operational needs. It transitions from being actively involved in call setup to removing itself when no longer required, optimizing the balance between providing call features and minimizing post-dial delay.

Inventive Principle:

Principle #15Dynamics

2Reliability

If an application server remains in the signaling path throughout call setup, then call feature processing can be provided, but network resource utilization increases

Engineering Contradiction:

Improvecall feature processingVSAvoidnetwork resource utilization

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The application server extracts itself from the signaling path after completing its call feature processing function. The server removes itself by sending a REFER message to redirect the signaling flow, thereby eliminating unnecessary signaling delays while maintaining the reliability of call feature processing.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The application server discards its role in the signaling path after completing its function, allowing network resources to be recovered and made available for other uses. This reduces unnecessary network resource utilization while maintaining call feature processing reliability.

Inventive Principle:

Principle #34Discarding and recovering

3Ease of operation

If excessive signaling is required in VoIP networks, then call setup can be controlled, but post-dial delay increases

Engineering Contradiction:

Improvecall setup controlVSAvoidpost-dial delay

Core Design Contradiction:

Ease of operationVSLoss of time

Solution Approach 1:

The application server extracts itself from the signaling path after completing its call feature processing function. The server removes itself by sending a REFER message to redirect the signaling flow, thereby eliminating unnecessary signaling delays while maintaining the reliability of call feature processing.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The application server performs necessary call feature processing in advance before removing itself from the signaling path. This preliminary action ensures that call setup control is maintained while minimizing subsequent signaling delays.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS7739395B1Call signaling in an IP network

Publication Date: 2010.06.15 AT&T CORP

AI summary

A method and apparatus for call setup signaling in a VoIP network is disclosed. An application server receives call information from a network node, which causes the application server to be inserted in the call setup signaling path. The application server provides any special feature processing necessary for call setup. Upon the application server determining that it is no longer required in the signaling path for call setup, the application server removes itself from the call setup signaling path. The application server may remove itself from the signaling path prior to completion of call setup, thereby freeing up network resources and reducing post dial delay. In various embodiments, the application server removes itself from the call setup signaling path by transmitting information utilizing particular protocol messages.