Despite reservations about cable's small-cells-as-a-service model, AT&T is working with multiple cable companies to test DOCSIS backhaul solutions in a variety of use cases.

Gordon Mansfield, AT&T Inc. (NYSE: T)'s AVP of Small Cell Solutions, says the carrier is exploring ways to work with cable companies to lease existing backhaul capacity. The carrier is still testing some use cases, but is in the deployment phase, he says, especially in the enterprise. (See Know Your Small Cell: Home, Enterprise, or Public Access?)

"We certainly use cable in some deployments," Mansfield tells Light Reading. "We have tested in some outdoor locations as well."

Backhaul, as well as site acquisition, remains the biggest challenge in small cell deployments, Mansfield says, which is why AT&T is open to working with cable companies. He has said in the past that it gets complicated in terms of who deploys, owns, and runs the small cell, but it's clear the operator is being flexible in its deployment strategy. (See Small Cells as a Service? Not So Fast, MSOs....)

"You have to look at all options -- cable, VDSL, wireless -- you have to look at the lowest cost that meets your engineering requirements," Mansfield says. "By doing that, you have multiple options depending on the geographic area you then have available."

AT&T has also been the most vocal about deploying multimode small cells that combine 3G and LTE. Mansfield said to expect these multi-standard small cells to hit the market in "very late 2014 to early 2015 when the ecosystem from chips through products" is ready. So far, it has deployed 3G HSPA+ small cells and is planning LTE single-mode small cells next. (See AT&T Gets 'Opportunistic' With 4G Small Cells and AT&T Readies LTE-Only Small Cells, Eyes Multimode by 2015.)

— Sarah Reedy, Senior Editor, Light Reading