SOURCE:http://www.pcmag.com/article2/0,2817,2333966,00.asp A month after Comcast imposed a bandwidth cap on its residential customers, AT&T announced this week that it is experimenting with a similar system that would limit usage to 150 Gbytes per month. As of November 1, new AT&T customers in Reno, Nevada will be allowed to use between 20GB and 150GB of bandwidth per month depending on their speed tier. The test is intended "to evaluate a usage-based model that could potentially help address today's trend of explosive bandwidth usage, [and] may be extended to one other market by the end of the year," according to an AT&T statement. Existing high-speed Internet customers in Reno who use more than 150GB of data per month will automatically be enrolled in the bandwidth trial by year's end, AT&T said. If trial participants exceed usage limits, they will be notified in writing and will receive a one-month grace period for their first infraction. If they do it again, however, customers will be charged $1 for every GB over their usage amount. AT&T will notify customers 60 days before overage charges appear on their bill. How do you tell how much bandwidth you're using? AT&T said it will provide its customers with a "bandwidth measuring tool" to determine their usage. The company will also notify customers when they reach 80 percent of their usage amount. Service will not be terminated for overuse, according to AT&T. "A small group of customers are using the majority of bandwidth on our network," according to AT&T. "In fact, almost 50 percent of total bandwidth is used by just five percent of customers – customers, for example, who are uploading and downloading the equivalent of more than 40,000 YouTube videos or 40 million e-mails a month. This kind of heavy usage has an impact on all of our customers." Comcast announced in August that all its residential customers will be subject to a 250GB per month data limit starting October 1. Comcast came under fire last year for cutting off service to customers who consumed a large amount of bandwidth but refusing to provide those customers with information on how much bandwidth they were able to use. The Federal Communications Commission (FCC) also handed down an enforcement action against Comcast in August for what the commission considered to be unreasonable network management. In April, file-sharing service Vuze also accused AT&T of throttling traffic on its network; a charge AT&T denied. AT&T has notified the FCC of its bandwidth cap plans, according to filings.