The largest carriers in the United States are collectively investing billions in enterprise network and service upgrades, but they are committing far more dollars to consumer and wireless services. One look at revenue potential and it becomes clear why -- the carriers stand to gain billions in new business as initiatives such as IPTV take hold.

But industry watchers are left to wonder: Are business customers getting short-changed?

While capital expenditures have increased at AT&T and Verizon Business, the two carriers are spending a disproportionate amount of money building out consumer-oriented services such as IPTV and related fiber-to-the-premises initiatives such as Verizon’s FiOS, says Lisa Pierce, a vice president at Forrester Research.

Click to see: Carrier spending limits

“My theory is that the two big providers are pouring most of capex into IPTV infrastructure, and that enterprise services innovation is suffering as a result," Pierce says.

For example, AT&T has plans to allocate roughly $17.9 billion to capital expenditures this year, according to research firm Infonetics. That’s about $1.1 billion more than 2006 figures, says Stéphane Téral, a principal analyst at Infonetics.

Of that $17.9 billion, $750 million is earmarked for enterprise service enhancements.

“We are targeting two areas for investment: our [service] portfolio and our global network reach and capabilities" for multinational customers, says Bill Archer, senior vice president of product management at AT&T. He says with this year’s investment the carrier is expanding its VPN, VoIP, managed hosting and managed security services, just to name a few target areas.

“Over two years [2006 and 2007] we will have invested over $1 billion in our portfolio and network for enterprise customers," Archer says. “Satisfying the global requirements of multinational customers is a strategic priority."

But despite its two-year, $1 billion investment, AT&T’s enterprise spending is still low, Pierce maintains. “AT&T is proportionately under-investing in enterprise landline operations and over-investing in consumer landline," she says.

Verizon, meanwhile, is expected to allocate $17.7 billion to capital expenditures in 2007, an increase from $600 million from 2006 figures, Téral says.

The carrier has not stated how much it will spend on enterprise operations; however, Infonetics estimates it will spend $10.7 billion to $10.9 billion on landline networks this year.