SIP Router Direct Routing to Serving Switch
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing systems for routing Voice over Internet Protocol (VoIP) calls in mobile networks are inefficient and costly due to the need to route calls through multiple mobile switching centers, leading to excessive usage of network resources.
Innovation Solution
The implementation of a Session Initiation Protocol (SIP) router that identifies the appropriate serving switch by sending a Send Routing Information (SRI) for Short Message (SM) to the Home Location Register, mapping the SIP address to an IP Address or Fully Qualified Domain Name (FQDN), and directly sending the SIP INVITE to the identified switch, thereby avoiding multiple routing centers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If calls are routed through multiple mobile switching centers to locate the user's mobile device, then the call can be properly communicated to the user, but the usage of network resources such as switches and voice ports increases
Solution Approach 1:
The system performs preliminary location lookup of the mobile device before call routing by querying the HLR with the MSISDN. This advance action identifies the target serving switch in advance, so that when the call arrives, it can be directly routed to the correct switch without passing through multiple intermediate switching centers, thus reducing network resource consumption while ensuring reliable call delivery
Solution Approach 2:
The SIP router acts as an intermediary between the VoIP network and the circuit-switched mobile network. It receives SIP INVITE messages, extracts the MSISDN, queries the HLR to find the target serving switch, and then routes the call directly to that switch. This intermediary function eliminates the need for multiple mobile switching centers to participate in the routing process, reducing network resource usage while maintaining call delivery reliability
2Reliability
If calls are routed through multiple mobile switching centers, then the call can reach the mobile device, but the routing process becomes inefficient and costly
Solution Approach 1:
The system performs preliminary location lookup of the mobile device before call routing by querying the HLR with the MSISDN. This advance action identifies the target serving switch in advance, so that when the call arrives, it can be directly routed to the correct switch without passing through multiple intermediate switching centers, thus reducing network resource consumption while ensuring reliable call delivery
Solution Approach 2:
The SIP router acts as an intermediary between the VoIP network and the circuit-switched mobile network. It receives SIP INVITE messages, extracts the MSISDN, queries the HLR to find the target serving switch, and then routes the call directly to that switch. This intermediary function eliminates the need for multiple mobile switching centers to participate in the routing process, reducing network resource usage while maintaining call delivery reliability
Data Source
AI summary
Systems and methods for a Session Initiation Protocol (SIP) router are described. In one aspect, the SIP router receives a SIP INVITE for an incoming call to a target mobile subscriber. Responsive to receiving the SIP INVITE, the SIP router identifies, via a Send Routing Information for Short Message (SRI/SM) request to a Home Location Register, a first address of a serving switch in a circuit-switched mobile network; a mobile telephony device associated with the target mobile subscriber is currently location-updated on the serving switch. The SIP router maps the first address to a second address for the serving switch; the second address being a SIP address. Using the SIP address, the SIP router sends the received SIP INVITE to a SIP interface of the serving switch. The serving switch being configured to process the received SIP INVITE and the incoming call to the target mobile subscriber.