And, of course, the consumer will continue to demand more and want more applications to work—right now. If a YouTube video is low resolution and stalling, Skype Voice is skipping, or Facebook is loading images slowly, then the user is having a bad experience. The challenge today is that many network operators don’t have a clear line of sight to determine what has occurred—and they often have even less when it comes to capabilities to fix the problem.

The Three Primary KPIs for Subscriber Experience 

Bandwidth, latency, and packet loss are the greatest determinants of a subscriber’s QoE. It is critical that operators continuously track subscriber traffic by each of these factors.     

1. Bandwidth

Bandwidth is an important measure of a subscriber’s broadband experience. High peak bandwidth capabilities may be a necessary condition but are not a sole determinant of the subscriber service experience. For instance, video streaming in particular is bandwidth-hungry, but it also needs long durations of high bandwidth access to deliver a quality service. In the case of video streaming, QoE metrics and remedial actions would need to consider both bandwidth and duration at a minimum.    

2. Latency

Latency is another important metric, especially for interactive applications. Few consumer plans offer latency as a service level agreement (SLA), but it is sometimes included as part of a managed service offering for business connections. Anyone who has ever played an online first-person shooter game can tell you that latency “literally” kills! For instance, high latency voice connections can introduce timing issues that lead individuals to inadvertently speak over one another, resulting in a very frustrating conversation.

3. Packet Loss

Packet loss is another important determinant of QoE and can result in increased buffering and stalls in video streaming, slow web page load times and jittery voice applications. Packet loss wastes bandwidth on the network as packets are retransmitted. In addition, depending on the application types, packet loss can wreak havoc on subscriber experience. For a web shopping session in a browser, packet loss of even 1 percent can result in doubled page-loading times, significantly impacting QoE and potentially driving shoppers away from that site.

These three factors—throughput, latency, and packet loss—are commonly identified by telecom regulatory authorities (TRAs) as the key metrics for a broadband operator to either measure or use to self-evaluate. The TRAs themselves will increasingly deploy measurement solutions as an independent authority on network performance; however, the question that immediately follows the collection of these key performance indicators (KPIs) is “are these good numbers?” The answer is, “it depends on the application.”

It’s All About that App

Any subscriber experience effort must also factor in the characteristics and the needs of the application in question. The table on the next page highlights the different ways that various applications can respond to disparities in traffic throughput (bandwidth), latency, and loss: