If mobile data traffic was a car, it would be moving at 60,000 miles an hour right now -- and obviously the wheels would come off. That's the analogy Senior EVP of Technology and Operations John Donovan shared with the Mobile World Congress crowd in Barcelona today.

He used the figure of speech to explain why AT&T's rapid shift to becoming a software company is essential if the carrier is going to keep up with the 100,000% increase in data traffic on its wireless network in the last eight years. The traditional approach to networking breaks down under that kind of growth pressure, despite the power of more sophisticated routers and other gear, he notes. And so AT&T Inc. (NYSE: T) is becoming a software company, through the adoption of software-defined networking and network functions virtualization, at an ever faster pace. (See AT&T Touts SDN Push, Seeks Talent.)

"We expect this approach to work," Donovan says in this blog post, which reflects his Barcelona comments. "We've proven it in our data centers." (See AT&T Reveals Audacious SDN Plans.)

By the end of 2014, AT&T moved 400 of its IT apps (or about 40% of its total strategic IT apps) to the cloud and it continues to migrate an app a day. That enables the carrier to operate at 50% greater efficiency than on dedicated hardware, which is why all strategic IT apps will be shifted to the cloud by mid-2017, Donovan says.

"We're taking those skills learned in the IT world to our software transformation of the wide area network (WAN), deploying our distributed AT&T Integrated Cloud into many of our 4600 central offices," he writes.

AT&T is currently migrating 29 nodes on which it is running virtualized functions to the AIC next-gen architecture, with plans to migrate 40 more by the end of this year. All of that work will enable the carrier to move 5% of the 150 network functions it ultimately hopes to virtualize and control to the next-gen architecture this year.

Donovan also highlighted AT&T's other progress to date for the Barcelona masses, including launching its Network on Demand service, enabled by SDN, and virtualization of its mobile packet core and its enterprise and consumer VoIP networks. The mobile packet core is moving to a common off-the-shelf hardware platform supporting virtualized functions, which is already enabling AT&T's Connected Car and MVNO services this year. The VoIP services will run on what AT&T calls its Virtualized Universal Service Platform. (See AT&T's Cloud Future Takes Shape and AT&T Brings User-Defined Network to Austin Businesses.)

These changes are producing a cultural shift and change in hiring practices to include many more software engineers, as well as fueling AT&T's high level of activity among open source groups, including OpenStack , ON.Lab , OpenDaylight and Open Platform for NFV Project Inc. , Donovan says. (See AT&T Seeks Help on Culture Change Issues).

— Carol Wilson, Editor-at-Large, Light Reading