System and method for real-time AAL2 channel detection in UTRAN
View Patent ↗A system and method for detecting channels in a network using messages passing through the network is provided. An embodiment comprises detecting AAL2 channels communicating between a Node B and an radio network controller and also between two radio network controllers. In the case of communication between a NodeB and a radio network controller, the AAL2 channels are detected by matching pairs of Random Access Channel (RACH) and Forward Access Channel (FACH) associated with a user equipment identity along with a Dedicated Channel (DCH) until the AAL2 channels present between the Node B and the RNC are determined to a desired level of confidence. In the case of communication between two radio network controllers, only the DCH channels need to be detected to completely detect the AAL2 channels.
1. A method for correlating access channels associated with a call in a UMTS Terrestrial Radio Access Network (UTRAN), comprising:
detecting one or more Random Access Channel (RACH) messages;
determining a User Equipment (UE) identity for each of the one or more RACH messages;
storing the UE identity for the one or more RACH messages in a database;
detecting a Forward Access Channel (FACH) message;
determining a UE identity for the FACH message;
searching the database for UE identity that was present in the RACH messages to match the UE identity that was present in the FACH message;
storing information associated with the matched UE identities in a database;
detecting one or more additional FACH messages, each of the additional FACH messages having the UE identity;
searching the database for UE identities that match the UE identities of the additional FACH messages; and
storing a number of additional pairs of matching UEs that are present in the FACH and RACH messages.
2. The method of claim 1 , further comprising:
validating a UE identity match by determining how many additional pairs are detected.
3. The method of claim 2 , further comprising:
validating the UE identity match when a predetermined number of additional pairs are detected.
4. The method of claim 3 , further comprising:
configuring the predetermined number by a network operator.
5. The method of claim 3 , further comprising:
configuring the predetermined number based upon a level of confidence required by a network operator.
6. The method of claim 1 , further comprising:
detecting the RACH and FACH messages on a Iub interface between a Node B and a Radio Network Controller (RNC).
7. The method of claim 1 , wherein the UE identity comprises an International Mobile Subscriber Identity (IMSI).
8. The method of claim 1 , wherein the UE identity comprises a Temporary Mobile Subscriber Identity (TMSI) combined with a Location Area Identity (LAI).
9. The method of claim 1 , wherein the UE identity comprises a Packet Temporary Mobile Subscriber Identity (PTMSI) combined with a Routing Area Identity (RAI).
10. A non-transitory computer-readable storage medium comprising instructions for correlating access channels associated with a call in a UMTS Terrestrial Radio Access Network (UTRAN), wherein the instructions, when executed, cause a processor to perform actions comprising:
detecting one or more Random Access Channel (RACH) messages;
determining a User Equipment (UE) identity for each of the one or more RACH messages;
storing the UE identity for the one or more RACH messages in a database;
detecting a Forward Access Channel (FACH) message;
determining a UE identity for the FACH message;
searching the database for UE identity that was present in the RACH messages to match the UE identity that was present in the FACH message;
storing information associated with the matched UE identities in a database;
detecting one or more additional FACH messages, each of the additional FACH messages having the UE identity;
searching the database for UE identities that match the UE identities of the additional FACH messages; and
storing a number of additional pairs of matching UEs that are present in the FACH and RACH messages.
11. The computer-readable storage medium of claim 10 , wherein the instructions, when executed, cause a processor to perform actions further comprising:
validating a UE identity match by determining how many additional pairs are detected.
12. The computer-readable storage medium of claim 11 , wherein the instructions, when executed, cause a processor to perform actions further comprising:
validating the UE identity match when a predetermined number of additional pairs are detected.
13. The computer-readable storage medium of claim 12 , wherein the instructions, when executed, cause a processor to perform actions further comprising:
configuring the predetermined number by a network operator.
14. The computer-readable storage medium of claim 12 , wherein the instructions, when executed, cause a processor to perform actions further comprising:
configuring the predetermined number based upon a level of confidence required by a network operator.
15. The computer-readable storage medium of claim 10 , wherein the instructions, when executed, cause a processor to perform actions further comprising:
detecting the RACH and FACH messages on a Iub interface between a Node B and a Radio Network Controller (RNC).
16. The computer-readable storage medium of claim 10 , wherein the UE identity comprises an International Mobile Subscriber Identity (IMSI).
17. The computer-readable storage medium of claim 10 , wherein the UE identity comprises a Temporary Mobile Subscriber Identity (TMSI) combined with a Location Area Identity (LAI).
18. The computer-readable storage medium of claim 10 , wherein the UE identity comprises a Packet Temporary Mobile Subscriber Identity (PTMSI) combined with a Routing Area Identity (RAI).
19. A network monitoring system comprising:
one or more passive monitoring probes coupled to network interfaces, the probes capable of capturing data packets from the network interfaces; and
a processor receiving the captured data packets from the probes, the processor operating to:
detect one or more Random Access Channel (RACH) messages;
determine a User Equipment (UE) identity for each of the one or more RACH messages;
store the UE identity for the one or more RACH messages in a database;
detect a Forward Access Channel (FACH) message;
determine a UE identity for the FACH message;
search the database for UE identity that was present in the RACH messages to match the UE identity that was present in the FACH message;
store information associated with the matched UE identities in a database;
detect one or more additional FACH messages, each of the additional FACH messages having the UE identity;
search the database for UE identities that match the UE identities of the additional FACH messages; and
store a number of additional pairs of matching UEs that are present in the FACH and RACH messages.
20. The monitoring system of claim 19 , wherein the processor is further operable to:
validate a UE identity match by determining how many additional pairs are detected.
21. The monitoring system of claim 20 , wherein the processor is further operable to:
validate the UE identity match when a predetermined number of additional pairs are detected.
22. The monitoring system of claim 21 , wherein the processor is further operable to:
configure the predetermined number by a network operator.
23. The monitoring system of claim 21 , wherein the processor is further operable to:
configure the predetermined number based upon a level of confidence required by a network operator.
24. The monitoring system of claim 19 , wherein the processor is further operable to:
detect the RACH and FACH messages on a Iub interface between a Node B and a Radio Network Controller (RNC).
25. The monitoring system of claim 19 , wherein the UE identity comprises an International Mobile Subscriber Identity (IMSI).
26. The monitoring system of claim 19 , wherein the UE identity comprises a Temporary Mobile Subscriber Identity (TMSI) combined with a Location Area Identity (LAI).
27. The monitoring system of claim 19 , wherein the UE identity comprises a Packet Temporary Mobile Subscriber Identity (PTMSI) combined with a Routing Area Identity (RAI).