DETERMINING DROPPED CALL RATES IN IP MULTIMEDIA NETWORKS

• US 20200137219A1
• Filed: 12/31/2019
• Published: 04/30/2020
• Est. Priority Date: 03/17/2017
• Status: Active Grant

• Current Assignee: T-Mobile USA, Inc. (Deutsche Telekom AG)
• Original Assignee: T-Mobile USA, Inc. (Deutsche Telekom AG)
• Inventors: Donnenwirth, Dawn, Munar, Le Roy, Zhang, Ting, Savar, Baquer Ali Chabuk, Rahman, Muhammad Tawhidur
• Granted Patent: US 11,178,274 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04M 15/41 Billing record details, i.e. parameters, identifiers, structure of call data record [CDR]
• CPC Class Codes: H04M 15/57 for integrated multimedia messaging subsystem [IMS]
• CPC Class Codes: H04M 15/60 based on actual use of network resources
• CPC Class Codes: H04M 15/63 based on the content carried by the session initiation protocol [SIP] messages
• CPC Class Codes: H04M 15/8083 involving reduced rates or discounts, e.g. time-of-day reductions or volume discounts
• CPC Class Codes: H04M 2215/0164 Billing record, e.g. Call Data Record [CDR], Toll Ticket[TT], Automatic Message Accounting [AMA], Call Line Identifier [CLI], details, i.e. parameters, identifiers, structure
• CPC Class Codes: H04M 2215/0188 Network monitoring; statistics on usage on called/calling number
• CPC Class Codes: H04M 3/2218 Call detail recording
• CPC Class Codes: H04M 7/0084 Network monitoring; Error detection; Error recovery; Network testing
• CPC Class Codes: H04W 4/24 Accounting or billing

Abstract

Systems and methods are described herein for determining dropped call rates (DCR) for various communications networks, such as IP Multimedia Networks (IMS), which include Voice over LTE (VoLTE) networks. For example, the systems and methods utilize data (e.g. abnormal cause codes) generated by layers of the IMS networks, such as a Session Initiation Protocol (SIP) layer of the IMS network, when determining dropped call rates for IMS networks.

Claims

1. At least one non-transitory computer-readable medium carrying instructions, which when executed by at least one data processor, determine performance of an IP Multimedia System (IMS) network, comprising:

identifying call detail records, wherein the identified call detail records include individual records that each include at least one Session Initiation Protocol (SIP) layer code associated with at least one session,

wherein the at least one session has at least one failure within at least one application layer of a Voice over LTE (VoLTE) network;

computing a dropped call or failed session rate for the VoLTE network based on identified call detail records with SIP layer codes for sessions having failures; and

initiating an action based on the computed dropped call or failed session rate for the VoLTE network.

2. The computer-readable medium of claim 1, further comprising:

accessing a baseline dropped call rate provided by a radio access network (RAN) component of the IMS network; and

adjusting the baseline dropped call rate with the computed dropped call or failed session rate for the IMS network to determine a modified call rate for the IMS network that is based on information obtained from a SIP layer of the IMS network and information obtained from a radio access layer of the IMS network.

3. The computer-readable medium of claim 1, wherein computing the computed dropped call or failed session rate includes determining an overall dropped call rate for the IMS network based on a single radio voice call continuity (SRVCC) dropped call rate for the IMS network, one or more access network dropped call rates, and a network disconnect dropped call rate for the IMS network.

4. The computer-readable medium of claim 1, wherein identifying call detail records includes selecting call detail records that contain a SIP 503 cause code identifying a service unavailable failure at a server within the IMS network.

5. The computer-readable medium of claim 1, wherein identifying call detail records includes selecting call detail records that contain a SIP 481 cause code identifying a transaction does not exist failure at a server within the IMS network.

6. The computer-readable medium of claim 1, further comprising applying a set of filtering criteria to the identified call detail records to identify a group of call detail records associated with a dropped call within the IMS network, including identifying call detail records that include information identifying a suitable duration for a communication session between two mobile devices.

7. The computer-readable medium of claim 1, further comprising applying a set of filtering criteria to the identified call detail records to identify a group of call detail records associated with a dropped call within the IMS network, including identifying call detail records that include a voice call having a disconnection at an originating mobile device and a call type of a mobile originating call (MOC).

8. The computer-readable medium of claim 1, further comprising applying a set of filtering criteria to the identified call detail records to identify a group of call detail records associated with a dropped call within the IMS network, including identifying call detail records that include a voice call having a disconnection at a terminating mobile device and a call type of a mobile terminating call (MTC).

9. The computer-readable medium of claim 1, wherein the IMS network is a Voice over LTE (VoLTE) network.

10. The computer-readable medium of claim 1, further comprising:

generating a report that presents a determined dropped call rate (DCR) for the IMS network.

11. A computer-implementable method to determine performance of an IP Multimedia System (IMS) network, the method comprising:

identifying call detail records, wherein the identified call detail records include individual records that each include at least one Session Initiation Protocol (SIP) layer code associated with at least one session,

wherein the at least one session has at least one failure within at least one application layer of a Voice over LTE (VoLTE) network;

computing a dropped call or failed session rate for the VoLTE network based on the identified call detail records with SIP layer codes for sessions having failures; and

initiating an action based on the computed dropped call or failed session rate for the VoLTE network.

12. The method of claim 11, further comprising:

accessing a baseline dropped call rate provided by a radio access network (RAN) component of the IMS network; and

adjusting the baseline dropped call rate with the computed dropped call or failed session rate for the IMS network to determine a modified call rate for the IMS network that is based on information obtained from a SIP layer of the IMS network and information obtained from a radio access layer of the IMS network.

13. The method of claim 11, wherein computing the computed dropped call or failed session rate includes determining an overall dropped call rate for the IMS network based on a single radio voice call continuity (SRVCC) dropped call rate for the IMS network, one or more access network dropped call rates, and a network disconnect dropped call rate for the IMS network.

14. The method of claim 11, wherein identifying call detail records includes selecting call detail records that contain a SIP 503 cause code identifying a service unavailable failure at a server within the IMS network.

15. The method of claim 11, wherein identifying call detail records includes selecting call detail records that contain a SIP 481 cause code identifying a transaction does not exist failure at a server within the IMS network.

16. The method of claim 11, further comprising applying a set of filtering criteria to the identified call detail records to identify a group of call detail records associated with a dropped call within the IMS network, including identifying call detail records that include information identifying a suitable duration for a communication session between two mobile devices.

17. The method of claim 11, further comprising applying a set of filtering criteria to the identified call detail records to identify a group of call detail records associated with a dropped call within the IMS network, including identifying call detail records that include a voice call having a disconnection at an originating mobile device and a call type of a mobile originating call (MOC).

18. The method of claim 11, further comprising applying a set of filtering criteria to the identified call detail records to identify a group of call detail records associated with a dropped call within the IMS network, including identifying call detail records that include a voice call having a disconnection at a terminating mobile device and a call type of a mobile terminating call (MTC).

19. The method of claim 11, wherein the IMS network is a Voice over LTE (VoLTE) network.

20. At least one non-transitory computer-readable medium carrying instructions, which when executed by at least one data processor, determine performance of an IP Multimedia System (IMS) network, comprising:

selecting call detail records having at least one cause code from a Session Initiation Protocol (SIP) layer associated with abnormal communication sessions for mobile devices having an IMS application layer;

identifying a group of call detail records with cause codes associated with a dropped call within the IMS network;

determining a dropped call rate for the IMS network based on the abnormal communication sessions for mobile devices having the IMS application layer within the identified group of call detail records; and

performing an action based on the determined dropped call rate for the IMS network.