Are the nation's LTE wireless carriers prepared for the video chat data crunch expected to come with the next-generation iPhone and other devices that are expected to launch this fall?
The answer: It depends on whom you ask.
Both AT&T and Verizon Wireless decline to say whether they are ready for the data crunch.
Over the summer, both carriers introduced data sharing plans that analysts believe were timed to help limit a surge in heavy data use expected especially with the use of Apple's FaceTime real-time video chat software on the iPhone.
"If I were a carrier, I'd be rather frightened by FaceTime," said Jack Gold, an analyst at J. GoldAssociates. "If everybody used FaceTime, bandwidth would go up dramatically, and the user experience would go down."
Imposing data sharing plans with set fees for specific numbers of gigabytes a month -- and penalties for exceeding the set amounts -- could help top carriers AT&T and Verizon avoid data capacity overload problems on their 4G LTE, and even 3G, networks, Gold said.
"Requiring the data sharing plans is really just another way for carriers to say they are limiting your access," he added.
AT&T has come under fire in recent days for announcing plans to require users to sign up for a Mobile Share data plan in order to conduct FaceTime video chats over its current 3G and future cellular networks.
FaceTime will be available for cellular network use, instead of just over Wi-Fi, in mobile devices running the forthcoming iOS 6, which Apple announced earlier this year.
Sprint, the nation's number three carrier, has stood solidly behinds its unlimited data plans, and is just starting to roll out 4G LTE technology.
At an event to mark the activation of its 16th LTE location in Baltimore earlier this week, Sprint 4G engineering manager Viet Chu told reporters that "if some abuse the system [with heavy data use] we would address it." He didn't specify what steps the carrier may take.
Concerns about FaceTime's impact on cellular networks are particularly acute, partly because the iPhone is the top selling smartphone model worldwide and because the next model will reportedly support LTE, which would help make the device even more popular.
The upcoming iPhone is also expected to have a larger screen -- more than 4-inches compared to the current modle's 3.5-in. screen -- which would make video chats easier.
That creates problems for carriers because like most two-way chat apps, FaceTime is an enormous bandwidth hog.
Video chat often uses about 3 megabytes of data per minute, though the exact rate depends on encoded software, noted Wendy Cartee, vice president of product and technical marketing for JuniperNetworks.
Juniper develops software that carriers can use to improve bandwidth at cell tower locations. It also sells a Universal Access router that can be installed at individual cellular tower locations to help streamline the data traffic at the point where it joins the backhaul link. Backhaul is the wired (or fiber optic) segment of a network between the wireless portion received at a cell tower and the network core.
Such products from Juniper and other vendors like Cisco and Alcatel Lucent should help U.S. carriers handle FaceTime, or other rich video applications on their LTE networks, Cartee said. "Carriers do plan for these types of changes in apps," she noted. "I'm looking forward to using FaceTime over cellular."
LTE is also inherently faster than 3G (generally LTE networks provide up to 8 Mbps on downlinks and up to 3 Mbps on uplinks) and can generally handle more capacity than earlier-generation networks, analysts noted.
Verizon offers LTE service in most of the geographic U.S. AT&T trails Verizon in coverage but has touted its GSM 3G HSPA speeds where its LTE networks aren't ready.
Gold said data sharing pricing plans will help AT&T and Verizon deal with the data crunch as much as the new routers and other technology.
"Before these data sharing limits, there was no reason for end users to do any kind of self-regulation," he explained. "Now if they use a lot of data, it will cost them."
As a result, Gold said AT&T won't get the heated criticism it got for not being able to support the original iPhone five years ago over GSM. "Data capacity will be much less of an issue with iPhone 5 than the first time around, which kicked AT&T's butt," Gold said.