Method to determine media paths in a SIP network using information from endpoints and intermediate devices

• US 20130100859A1
• Filed: 10/24/2011
• Published: 04/25/2013
• Est. Priority Date: 10/24/2011
• Status: Active Grant

• Current Assignee: Edgewater Networks Incorporated (Ribbon Communications, Inc.)
• Original Assignee: Edgewater Networks Incorporated (Ribbon Communications, Inc.)
• Inventors: Martin, David Samuel, Bauch, David, Strametz, Karin
• Granted Patent: US 8,971,193 B2
• Time in Patent Office: Days
• US Class Current: 370/259
• CPC Class Codes: H04L 12/1482 involving use of telephony infrastructure for billing for the transport of data, e.g. call detail record [CDR] or intelligent network infrastructure
• CPC Class Codes: H04L 43/04 Processing captured monitoring data, e.g. for logfile generation
• CPC Class Codes: H04L 43/106 using time related information in packets, e.g. by adding timestamps
• CPC Class Codes: H04M 15/48 Secure or trusted billing, e.g. trusted elements or encryption
• CPC Class Codes: H04M 15/56 for VoIP communications
• CPC Class Codes: H04M 15/63 based on the content carried by the session initiation protocol [SIP] messages

Abstract

An internet telephony call analyzer receives call information from endpoint and intermediate network devices, corrects timestamp errors in the records, stores the records, and identifies records associated with a single call session between two endpoint devices in the network. The timestamp errors may be corrected by applying a time differential correction to a call start timestamp and call stop timestamp of the record if the timestamp in the record differs from a system timestamp when the record was received by the call analyzer. Call information records associated with the same call session may be matched by identifying records with the same SIP call ID, the same SSRC ID and call start timestamps within a predetermined time interval of each other.

Claims

1. A method for analyzing internet telephony calls, the method comprising:

receiving by a call analyzer via internet protocol multiple call information records from multiple endpoint and intermediate devices in a network;

correcting by the call analyzer timestamp errors in the received multiple call information records;

storing by the call analyzer the received call information records;

identifying by the call analyzer a set of matching call information records from among the multiple call information records, wherein the set of matching call information records are associated with a single call session between two endpoint devices in the network.

2. The method of claim 1 wherein correcting timestamp errors in the received multiple call information records comprises comparing a timestamp in a record of the multiple call information records with a system timestamp of the call analyzer when the record was received by the call analyzer, and, if the timestamp in the record differs from the system timestamp, applying a time differential correction to a call start timestamp and call stop timestamp of the record.

3. The method of claim 1 wherein each of the call information records comprises a call timestamp, an SIP Call-ID value from an SIP header, and an SSRC identifier from an RTP packet header.

4. The method of claim 1 wherein identifying the set of matching call information records comprises using SIP call ID information in the multiple call information records, SSRC ID information in the multiple call information records, and timestamp information in the multiple call information records to identify matching records associated with the single call session.

5. The method of claim 1 wherein identifying the set of matching call information records comprises identifying records with a same SIP call ID, a same SSRC ID and call start timestamps within 300 seconds of each other.