FaceTime Would Crash Mobile Cell Sites

At 667 Kbps, just 20 FaceTime users would saturate a 14 Mbps HSPA based 3G cell even if one assumes no scarcity at the base station backhaul, and that every user was in perfect range operating at the peak transmission/receive rates, and that there was no other traffic on the network.

That's why FaceTime is limited to Wi-Fi operation.

Digital Society � Blog Archive � Estimate of network bandwidth for iPhone 4 FaceTime

Will Apple Be First to Make the Video Calling Breakthrough?

Lots of people will point out that person-to-person video calling appliances and features have been available for a while. Most of us would point to Skype, while others would point to the capabiltiies Nokia has been offering on its high-end phones, or the specialized video telephony products now on the market.

Apple's new  iPhone 4 "FaceTime" video calling feature might be notable, though. People will have different opinions about the ease of use for Skype video telephony, but the big snag for most consumer video telephony appliances has been the need to buy them in pairs.

The iPhone 4 might be the first "appliance" supporting video telephony that does not actually have to be "bought in pairs," given the huge installed base the device is likely to have, globally. The other angle is that video telephony could become a "mere feature" of the most-widely-used communications appliance on the planet, though of course for the moment only on Apple iPhones from version 4 and forward.

Video calling might be a social function and therefore there is a network effect not possible when the units are deployed pair by pair.

Some significant sub-set of the mobile user population uses iPhones. In my own family, for example, all four of my children use iPhones, and it appears iPhone use among their peers is just about that high.

By confining FaceTime sessions to Wi-Fi connections, Apple avoids the almost-certain uneven quality of experience users would experience on AT&T's 3G network.

Innovations sometimes, perhaps ever, solely or primarily dependent on development of new technology. More commonly, it is a combination of ease of use, user installed base, price and the face that lots of other people seem to be doing it. Up to this point, almost no users had to worry about "everybody else doing it." That could change, beginning with the iPhone 4.

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