Verizon is planning to deploy 4G small cells in 2013 as part of an incremental program of LTE-Advanced "improvements" to its network. The operator hasn't said exactly when this will happen yet. (See Verizon Ready for LTE Small-Cell Advance.)

Nonetheless, it is expected by analysts that AlcaLu and Ericsson are likely to be part of the picture. Moreover, Chris Antlitz, analyst in the networking & mobility practice at Technology Business Research Inc. (TBR) suggests that Cisco could get a slice of the small cell pie indoors.

"Ericsson and Alcatel-Lucent are the most likely candidates for small cells, but I would not count out Cisco, especially for indoor cells," the analyst tells Light Reading Mobile. "They are a key supplier to Verizon and have some very competitive small cell technology."

Cisco hasn't introduced an LTE small cell to complement its 3G microcell offering yet. The company has said, however, that a 4G update is "a priority." (See Cisco: LTE Small Cell Is a 'Priority'.)

The vendor is shy about talking up a tiny 4G base station and potential users thereof at the moment, however. "We do not comment on a rumor or speculation that involves a customer," a spokesman told LR Mobile when we asked about a possible Verizon 4G small cell.

If Cisco is the wild card in the pack indoors, however, there's good reason to think that Verizon will stick with its macrocell providers for higher-power outdoor small cells: Simply to ensure that the entire network -- from the core to the very edge -- will interoperate properly.

"Operators want a multi-vendor environment, but outdoors I'm not sure many are ready to take the gamble yet," says Gabriel Brown, senior analyst at Heavy Reading.

This is because carriers are still concerned with management, synchronizing transmissions and inference between the macro networks and a growing network of small cell radios.

Timing is crucial in a flat-IP data-driven network but -- while synchronization standards are out there -- carriers and vendors haven't standardized on a specific set yet. (See A Sync Standards Rumble at the Edge?)

Radio interference meanwhile gets to be more of an issue as transmit power increases. Operators need self-optimising techniques implemented at the small cell to help with radio optimization and deployment but, again, the standards are lacking.

Brown expects that for higher-power and outdoor deployments -- with radio transmit power of power of 1 watt or more -- it will mean "less risk" for carriers to use their existing LTE suppliers.

For indoor lower power deployments -- around 100mw -- he expects that more than multiple vendors could be an option.

Verizon isn't ready to say either way yet. "No info for you on that at this time," a spokesman for the operator told us Wednesday.

— Dan Jones, Site Editor, Light Reading Mobile