Mobile operators worldwide are in the midst of a major technical evolution. In the past, bulk of the service revenues were derived from voice services, with a small amount generated from low-bandwidth data services such as phone-based internet browsing. However, due to the development of interactive mobile applications, enhancements in access network technologies such as 3.5/3.75G and overall increased customer expectations, the demand for mobile data services has skyrocketed.
The Asia Pacific presents a unique case study for the evolution of multi-service networks as countries are at vastly different stages in the adoption cycle of wireless services. For example, Taiwan and Hong Kong are at nearly 100% mobile adoption rate while India is still trying to break 10%. Likewise, countries like Japan are rapidly deploying 3.75G technologies such as high-speed packet access while others such as India and Thailand are still in the early adoption phases of 2.5G/2.75G such as GPRS and Enhanced Data Rates for GSM Evolution.
As the early adopters have experienced, the transition to converged networks supporting mobile data services presents a complicated challenge. For a successful transition, the operator must optimize both the core and access networks for the new services then - immediately after the services are introduced - carefully monitor and optimize them.
This new world of converged mobile networks and mobile data services has greatly expanded the role of network troubleshooting and monitoring tools. In essence, they have transitioned from being a 'necessary evil' for maintaining the network to a key business enabler that allows operators to rapidly expand their service portfolios and at the same time reduce operating expenses. Effective use of test and monitoring can speed up and optimize the introduction of mobile data services while the operator migrates to a converged next-generation network.
Core weakness
Existing 2.5G and 3G data services are still relatively expensive and are used primarily by businesses for internet access and email. However, as operators migrate to 3.5 and 3.75G access technologies, they will experience a burst in network usage driven by three factors - the migration of traditional circuit switched services to packet switched technology; delivery of the new services and; less expensive 'flat' rates increasing customer demand.
At this point, the core of the mobile network is one of the most vulnerable areas because this typically tailored to access network throughput. For example, as the operator migrates from GSM to UMTS, core infrastructure weaknesses are amplified.
As a part of core optimization, the operator needs to monitor all activity occurring over network elements interconnected through protocols such as ISUP, MAP, INAP, CAMEL, SMS, GSM-Abis and GSM-A. The operator must simultaneously correlate information exchanged by each device involved in transactions, including those on the internal signaling network as well as external connections for calls made to and from subscribers of other operators.
There are many signaling exchanges and interfaces involved during data transactions, each giving a different level of visibility into network and service issues. For example, the Gn interface is the most crucial in providing overall visibility into the network such as in 'macro' problems and issues related to authentication with external networks. Meanwhile, the Gi interface provides information on the quality of IP traffic and services. So unless the Gn and Gi interfaces are correlated, there is no way to test the interconnection between the operator data network and the external data network such as the internet.