Editor’s Note: The following article is reprinted from Network World.
For the past year, AT&T has been hit with bad PR over customer complaints about its 3G data service, despite the fact that recent
studies have shown it to have the fastest average download speeds of any other network in the United States. This has led AT&T to aggressively push back and make the iPhone a scapegoat for its network woes, as the company has essentially argued that the data demands created by the iPhone are unprecedented.
But a new study from ABI Research suggests that this claim simply doesn’t hold up, as it found that both Sprint and Verizon each carried more than 16 billion more megabytes of mobile network data than AT&T did in 2009 over its wireless network. ABI says this is mostly due to Sprint and Verizon having significantly more customers who use their laptops over their wireless networks than AT&T has.
ABI Practice Director Dan Shey says that while high-end smartphones such as the iPhone consume a lot more data than typical mobile phones, they still consume only one-tenth of the data that a typical laptop consumes over a mobile data connection. So while the iPhone may indeed eat up a significant chunk of AT&T’s 3G data traffic, it still puts much less strain on the network than laptop connections.
But if AT&T’s 3G network handles less overall data than its rivals and if it offers faster overall speeds than Verizon and Sprint, shouldn’t it offer iPhone users the highest level of overall service? Why all the complaints?
Shey posits a couple of theories over why customers might find their iPhone service to be less than optimal. First of all, while AT&T’s 3G network is on average faster than Verizon’s or Sprint’s, it has a vastly smaller footprint. This means that iPhone users could experience significant drop offs in their service if they simply travel to an area that only has 2G coverage.
Additionally, the faster speeds in areas where AT&T does have 3G coverage could result in a large concentration of high-end users consuming very large quantities of data on their iPhones in a relatively small area. So iPhone users who know where their 3G coverage might be strongest could all download more data from those areas at the same time, thus degrading the overall experience.
“Generally customers will use their devices more and for longer periods of time in network areas with faster connection speeds,” explains Shey. “I think we have all experienced this. I think with AT&T you tend to get more usage in certain faster parts of the network driving up utilization. Higher concentrations of data connections with longer use times increases overall network utilization.”
In other words, having a high concentration of iPhone users in a relatively small area creates a “tragedy of the commons” situation where the whole network is slowed during peak hours despite offering faster overall service than its competitors. This, Shey says, is why the size of a network footprint matters: If users can expect a consistent level of service from their 3G network wherever they’re located, they’re less likely to consume heavy amounts of data in a concentrated area.
So what, then, can AT&T do about this? The company has already invested significant resources into improving the performance of its 3G network over the past year, with its biggest initiative being the roll out of HSPA 7.2 technology intended to significantly boost speeds on its GSM-based network. The company has also bet that deploying its 3G network over stronger spectrum on the 850MHz band will solve some of the big capacity and propagation problems that have given iPhone users headaches in major markets such as New York and San Francisco. While these initiatives won’t solve the company’s problem with its footprint size, they will give its network more capacity to work with until it switches over to 4G LTE technology in 2011.
“They put a lot of work into their network in 2009 and I expect this to pay off moving forward,” says Shey, who also thinks AT&T’s experience with managing iPhone traffic has taught it some valuable lessons about mobile traffic management that will help it in the future. “Based on AT&T’s network traffic levels they probably have a higher concentration of traffic due to their smaller 3G footprint areas relative to Verizon and Sprint. I believe this shows that they are actually doing a good job of managing data traffic flows.”