The Universal Mobile Telecommunications System (UMTS) is a third-generation (3G) mobile phone technology standardized first by the European Telecommunications Standards Institute (ETSI) and now by the 3rd Generation Partnership Project (3GPP). UMTS carries both circuit switched (CS) and packet switched (PS) traffic using Wideband Code Division Multiple Access (W-CDMA) as its air interface. The description of the network components and protocols used in UMTS are well known to those of ordinary skill in the art and are available to the public from 3GPP, ETSI, and other sources. The UMTS network architecture consists of three domains: Core Network (CN), UMTS Terrestrial Radio Access Network (UTRAN), and User Equipment (UE).
The UTRAN provides the air interface access to subscribers' UE. Base stations in the UTRAN are referred as Node-Bs, and the control equipment for the Node-Bs is called a Radio Network Controller (RNC). The UMTS User Equipment communicates via the WCDMA air interface to the Node-Bs. The UE may be attached to either the PS domain or CS domain or both. The UE is capable of simultaneously using PS services and CS services.
The Asynchronous Transfer Mode (ATM) is used for data transmission in UMTS. The ATM layer multiplexes and demultiplexes and routes ATM cells, and ensures their sequence from end to end. The ATM Adaptation Layers (AAL) are responsible for the creation and reception of payloads through the lower layers of ATM on behalf of different applications. ATM Adaptation Layer type 2 (AAL2) handles circuit switched connections and packet connection protocol AAL5 is designed for data delivery.
One disadvantage of the prior art is the difficulty in identifying messages related to the same call for individual subscribers. Because multiple UEs are communicating with Node Bs and RNCs at the same time, thousands of data and control messages per second can be passed between a Node B and an RNC and between the RNCs. These messages follow several different protocol formats depending upon the purpose of the message. As a result, the messages passing on interfaces in the UTRAN do not provide sufficient information to determine which messages are related to the same subscriber.
A second disadvantage of the prior art is the difficulty in identifying related call records that are associated with different protocols. Individual call records may be established for messages of a particular protocol type. However, call records for different protocols may be related to the same call, but the call records do not comprise information that allows correlation across protocol types.