LTE Challenges | NETSCOUT

LTE Challenges

Business and consumer demand for wireless services is accelerating rapidly. In the last few years, the volume of information flowing over wireless networks in support of voice, data, and video communications has risen by an order of magnitude. In parallel, subscribers expect superior, consistent quality of service regardless of network utilization or their location – whether they are on the move or within a building.

Carriers are responding by upgrading their core networks and mobile access network, and offloading mobile data traffic via in-building wireless (IBW) networks. As service providers migrate from 2G and 3G to 4G via Long Term Evolution (LTE), the core network infrastructure transitions from a combination of circuit-switched and packet-switched technologies to an all-IP architecture. IBW networks also must undergo a paradigm shift with respect to their legacy counterparts in order to meet coverage, capacity, and performance requirements.

To unleash the full power of LTE, carriers need the right tools as they design, implement, and operate core and IBW networks. Legacy tools weren’t developed with today’s users and production environments in mind. Tools must be intelligent, intuitive, and lightweight to help carriers quickly and cost-effectively build optimized networks and identify, isolate, and resolve anomalies in order to deliver the breadth, depth, and quality of services that create a competitive edge.

Trends in Mobile Network Traffic

The age of mobility has arrived, but the mobility wave has hardly begun to form, much less crest. Mobile network traffic will explode, thanks not only to device proliferation, but also to the increasing demand for video and data services in addition to voice. According to the Cisco VNI Global Mobile Data Forecast 2012-2017, 66 percent of the world’s mobile data traffic will be video by 2017. Mobile data traffic will experience a 66 percent compound annual growth rate from 2012 to 2017 (a rate three times faster than global IP fixed traffic), reaching 11.2 exabytes per month globally by 2017. Meanwhile, carriers are under enormous pressure to deliver an outstanding quality of service (QoS) to maintain customer loyalty and minimize churn. Competition for subscribers comes from other carriers, as well as free/over-the-top offerings.

To succeed in this environment, carriers must execute a pair of initiatives. First, they must upgrade the core wireless network from 2G/3G to 4G, and Long-Term Evolution (LTE) is the path to get there. Second, they must offload as much traffic as possible from the macro wireless network to in-building wireless (IBW) networks. Approximately 80 percent of today’s mobile data traffic originates inside a building, and that number is likely to rise. At the same time, roughly 50 percent of this traffic originates in only 10 percent of all buildings, creating a serious mismatch in terms of where coverage is required versus where it is available. IBW options including distributed antenna systems (DAS), small cells (such as femtocells, picocells, metrocells, and microcells), and Wi-Fi help address these challenges.

Key Considerations

There are three critical characteristics carriers must keep in mind as they respond to these trends. One is coverage. Subscribers expect to be able to access services regardless of their location, be it static or on-the-move. Another is capacity. Carriers must optimize the end-to-end network to handle bandwidth-intensive offerings like streaming video for rising subscriber volumes. The final characteristic is performance, which encompasses not only QoS, but also rapid, accurate response to network anomalies and reports of substandard user experiences. The trick for carriers is to provide coverage, capacity, and performance as cost-effectively as possible, taking capital and operating expenditures into account.

With LTE, the architecture of the core network changes to an all-IP infrastructure. With an unprecedented number and speed of IP packets flowing over the network, legacy performance monitoring and troubleshooting solutions, which were tuned and scaled for pre-LTE architectures, are no longer appropriate.

For IBW, the infrastructure also must change. Macro networks typically were designed for limited numbers of users executing a limited subset of services like voice. With the impending mobile data tsunami, IBW solutions are ideally positioned to deliver the required coverage, capacity and quality. Given the scope of the IBW footprint, carriers cannot address this challenge alone – they must turn to system integrators, enterprises (who may have their own vested interests in the best coverage and capacity for their venue, and may share the burden of the deployment cost), and other parties to design and implement new IBW networks that minimize radio frequency interference and provide sufficient isolation from the macro network to maximize performance and core network offloading.

Best Practices

At the end of the day, carriers must deliver a QoS that produces a compelling user experience, regardless of the service offerings the subscriber is accessing, the subscriber’s location, or the number of subscribers requiring simultaneous service fulfillment. To do so, carriers need the right tools to support them during core and IBW design, deployment, and operation. The right tools are:
  • Intelligent – Functional breadth and depth are critical, as are visibility and the capability to correlate information from multiple domains (such as the core network’s user and control planes) for accurate root cause analysis of issues.
  • High-Performance – Scale and speed of tools must match that of the network and the services flowing across it.
  • Easy-to-Use – IT, engineering, and field resources are overloaded; powerful solutions with clear, intuitive user interfaces are worth their weight in gold.
  • Portable – Mobile networks require mobile tools that are lightweight and can be deployed where they are needed quickly.
  • Cost-Effective – Powerful tools with these qualities minimize time-to-value and maximize return-on-investment by eliminating the need for an array of heterogeneous solutions that drive up capital and operating expenditures.

On the core network, for example, most performance management solutions were developed for circuit-switched networks. When faced with the speed and volume of an all-IP network, legacy solutions drop packets and overflow storage, making it impossible to find the source of an anomaly or track-and-trace intermittent problems that occur over an extended period of time.

For IBW networks, carriers, system integrators, and building tenants and owners typically conduct spectrum analysis only in conjunction with final network testing, because spectrum analyzers traditionally have proven to be expensive, bulky, and complicated to use. When problems are detected this late in the game, re-work is costly and time-consuming. Lightweight, user-friendly, inexpensive analyzers with robust functionality allow for testing at every phase of the IBW development lifecycle. Identifying issues early mitigates risk, reduces the cost to respond, and keeps IBW deployment on schedule.

Network Time Machine™ for Service Providers
Ultimate Troubleshooting Machine for LTE Networks

Network Time Machine (NTM) is the first solution to provide back-in-time root cause analysis, down to the packet level, supporting 20Gbps LTE traffic on both portable and rackmount platforms. Its plug-and-play operation supports automatically identifying LTE subscribers from captured traffic; assessing each subscriber’s mobility and session management transactions, as well as identifying issues in the user-friendly UI.

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