As promised, Verizon Wireless has implemented its network optimization policies, which many interpret as data throttling but the company says are not.

The network optimization policies apply only to customers with 3G devices who were grandfathered in with unlimited data plans. Only the top 5 percent using the most data are subject to having their data speeds reduced when connected to a congested cell site. LTE users are not affected, although the company reserves the right to implement network management policies for LTE in the future.

In its disclosure/FAQ section, Verizon explains that the difference between its network optimization practices and throttling is network intelligence. "With throttling, your wireless data speed is reduced for your entire cycle, 100 percent of the time, no matter where you are," the company states. "Network Optimization is based on the theory that all customers should have the best network possible, and if you're not causing congestion for others, even if you are using a high amount of data, your connection speed should be as good as possible."

So, if you're in the top 5 percent of data users, your speed is reduced only when you are connected to a congested cell site. Once you are no longer connected to a congested site, your speed returns to normal, which could mean a matter of seconds or hours depending on the customer's location and time of day, the carrier says.

Just how do customers know if they're in that top 5 percent of affected data users? Verizon says the top 5 percent of data users, as of August, were using 2 GB or more of data each month.

Verizon offers tools to customers to monitor and manage their data usage and gives examples of what can be done with less than 2 GB of data in a month, such as: send 7,500 emails; visit 750 web pages; stream 150 minutes of music, 1 hour of high-resolution video and 5 hours of low-resolution video; and upload 60 photos.

Verizon began alerting customers back in February that it would invoke data management and data optimization practices. It started implementing video optimization in February in a number of markets and says it will continue to do so.