System and Method for Automatic Discovery of Topology in an LTE/SAE Network

• US 20110153844A1
• Filed: 12/18/2009
• Published: 06/23/2011
• Est. Priority Date: 12/18/2009
• Status: Active Grant

• Current Assignee: NetScout Systems Texas, LLC (NetScout Systems Incorporated)
• Original Assignee: Tektronix Incorporated (Fortive Corp.)
• Inventors: Bovo, Antonio, Chen, Xiaoju
• Granted Patent: US 8,307,097 B2
• Time in Patent Office: Days
• US Class Current: 709/228
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 43/12 Network monitoring probes
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition

Abstract

A system, method and computer program product are disclosed for monitoring a telecommunications network that comprises a plurality of Mobility Management Entity (MME) nodes and a plurality of evolved UTRAN NodeB (eNodeB) nodes coupled by S1-MME interfaces. A Stream Control Transmission Protocol (SCTP) association identifier is assigned to an SCTP association between interconnected MME and eNodeB nodes. Specific S1-MME messages allow discovering the MME nodes and the eNodeB nodes with their network identifiers, identifying the connections between them and populating proper tables for this topology information.

Claims

1. A method of monitoring a telecommunications network, the network comprising a plurality of Mobility Management Entity (MME) nodes and a plurality of evolved UTRAN NodeB (eNodeB) nodes, the MME nodes and eNodeB nodes coupled by S1-MME interfaces, wherein a Stream Control Transmission Protocol (SCTP) association identifier is assigned to an SCTP association between interconnected MME and eNodeB nodes, the method comprising:

capturing an S1-MME message from the S1-MME interfaces via a monitoring probe in a network monitoring system;

creating an MMEGI-MMEC key comprising an MME Group Identifier (MMEGI) and an MME Code (MMEC) in the S1-MME message;

associating an SCTP association identifier to the S1-MME message;

identifying a Tracking Area Identity (TAI) in the S1-MME message;

adding the SCTP association identifier from the S1-MME message to a list of SCTP association identifiers for an entry in an MME topology table, wherein the MME topology table entry corresponds to the MMEGI-MMEC key;

creating a TA-MMEC key from the TAI and MMEC parameters in the S1-MME message; and

adding one or more additional SCTP association identifiers to the list of SCTP association identifiers in the MME topology table, wherein the one or more additional SCTP association identifiers are from an entry in a TA-MMEC table, the TA-MMEC table entry corresponding to the TA-MMEC key.

2. The method of claim 1, wherein the S1-MME message comprises a Globally Unique MME Identity (GUMMEI), and wherein the MME Group Identifier (MMEGI) and the MME Code (MMEC) are part of the GUMMEI.

3. The method of claim 2, further comprising:

creating a new entry in the MME node topology table, if the MMEGI-MMEC key is not found in the MME node topology table, wherein the new entry comprises the MMEGI-MMEC key, the TAI, and a GUMMEI group identifier; and

wherein the new entry further comprises SCTP association identifier associated with the S1-MME message, if the Globally Unique Temporary Identity (GUTI) in the S1-MME message is for a current MME.

4. The method of claim 3, further comprising:

searching the MME topology table for existing entries that include the SCTP association identifier associated to the S1-MME message; and

if an existing entry includes the SCTP association identifier from the S1-MME message, then grouping the existing entry and the new entry together in the MME topology table.

5. The method of claim 4, further comprising:

grouping the existing entry and the new entry by assigning a same GUMMEI group identifier to both entries.

6. The method of claim 1, further comprising:

selecting an SCTP association identifier from an MME entry in the MME topology table;

comparing the selected MME table SCTP association identifier to SCTP association identifiers stored in an entry in an eNodeB topology table; and

if the selected MME table SCTP association identifier matches one of the eNodeB table SCTP association identifiers, then adding an entry to an MME-eNodeB links table, the MME-eNodeB links table entry comprising an MME identifier, an eNodeB identifier, and the matching SCTP association identifier.

7. The method of claim 6, wherein the MME identifier comprises the MMEGI, the MMEC, and a Globally Unique MME Identity (GUMMEI);

and

wherein the eNodeB identifier comprises an eNodeB global identifier.

19. The method of claim 1, further comprising:

selecting an SCTP association identifier from an MME entry in an MME topology table;

comparing the selected MME table SCTP association identifier to SCTP association identifiers stored in an entry in the eNodeB topology table; and

if the selected MME table SCTP association identifier matches one of the eNodeB table SCTP association identifiers, then adding an entry to an MME-eNodeB links table, the MME-eNodeB links table entry comprising an MME identifier, an eNodeB identifier, and the matching SCTP association identifier.

20. The method of claim 19, wherein the MME identifier comprises an MME Group Identifier (MMEGI), an MME Code (MMEC), and a Globally Unique MME Identity (GUMMEI);

and

wherein the eNodeB identifier comprises the eNodeB global identifier.

8. A method of monitoring a telecommunications network, the network comprising a plurality of Mobility Management Entity (MME) nodes and a plurality of evolved UTRAN NodeB (eNodeB) nodes, the MME nodes and eNodeB nodes coupled by S1-MME interfaces, wherein a Stream Control Transmission Protocol (SCTP) association identifier is assigned to an SCTP association between interconnected MME and eNodeB nodes, the method comprising:

capturing an S1-MME message from the S1-MME interfaces via a monitoring probe in a network monitoring system;

identifying an MME Code (MMEC) in the S1-MME message;

identifying a Tracking Area Identity (TAI) in the S1-MME message;

associate an SCTP association identifier to the S1-MME message;

creating a TA-MMEC key from the TAI and MMEC parameters in the S1-MME message;

adding the SCTP association identifier from the S1-MME message to a list of SCTP association identifiers for an entry in a TA-MMEC table, wherein the TA-MMEC entry corresponds to the TA-MMEC key; and

adding the SCTP association identifier from the S1-MME message to a list of SCTP association identifiers for an entry in an MME topology table, wherein the entry in the MME topology table corresponds to the TA-MMEC key.

9. The method of claim 8, further comprising:

determining that a Globally Unique MME Identity (GUMMEI) parameter is not present in the captured S1-MME message.

10. The method of claim 8, wherein the S1-MME message comprises an S-Temporary Mobile Subscriber Identity (S-TMSI), and wherein the MME Code (MMEC) is part of the S-TMSI.

11. The method of claim 8, further comprising:

creating a new entry in the TA-MMEC table if no entry in the TA-MMEC table matches the TA-MMEC key.

12. The method of claim 11, wherein the new entry comprises the SCTP association identifier from the S1-MME message.

13. The method of claim 8, further comprising:

selecting an SCTP association identifier from an MME entry in the MME topology table;

comparing the selected MME table SCTP association identifier to SCTP association identifiers stored in an entry in an eNodeB topology table; and

if the selected MME table SCTP association identifier matches one of the eNodeB table SCTP association identifiers, then adding an entry to an MME-eNodeB links table, the MME-eNodeB links table entry comprising an MME identifier, an eNodeB identifier, and the matching SCTP association identifier.

14. The method of claim 13, wherein the MME identifier comprises the MMEGI, the MMEC, and a Globally Unique MME Identity (GUMMEI);

and

wherein the eNodeB identifier comprises an eNodeB global identifier.

15. A method of monitoring a telecommunications network, the network comprising a plurality of Mobility Management Entity (MME) nodes and a plurality of evolved UTRAN NodeB (eNodeB) nodes, the MME nodes and eNodeB nodes coupled by S1-MME interfaces, wherein a Stream Control Transmission Protocol (SCTP) association identifier is assigned to an SCTP association between interconnected MME and eNodeB nodes, the method comprising:

capturing an S1-MME message from the S1-MME interfaces via a monitoring probe in a network monitoring system;

identifying an eNodeB global identifier key in the S1-MME message;

associating an SCTP association identifier to the S1-MME message;

adding the SCTP association identifier from the S1-MME message to a list of SCTP association identifiers for an entry in an eNodeB topology table, wherein the entry in the eNodeB topology table corresponds to the eNodeB global identifier key.

16. The method of claim 15, further comprising:

creating a new entry in the eNodeB topology table if no entry in the eNodeB topology table matches the eNodeB global identifier key.

17. The method of claim 16, wherein the new entry in the eNodeB topology table comprises the SCTP association identifier from the S1-MME message.

18. The method of claim 16, wherein the eNodeB global identifier key is part of the eUTRAN CGI (Cell Global Identifier).