Consolidation in the online ad network space continued today with news that Cox Enterprises has acquired Adify.

The deal gives Cox, which owns radio, TV and cable systems across the U.S., access to one of the few remaining independent companies in the space.

Adify, which powers a slew of vertical ad networks with its proprietary technology, will operate as an independent company. According to Russ Fradin, who will continue to run Adify, the company will support both Cox-owned websites as well as publishers run by the media conglomerate's competitors.

In recent months, ad networks, which many critics have decried as being difficult to tell apart, have received a great deal of attention. Some of that press has been unwanted, as evidenced by ESPN's dramatic decision to shun ad networks, while other stories have focused on how some media buyers are turning to ad networks to cut costs during tough economic times. 

But the one story that seems to endure has been the continuing consolidation in the space. Earlier this month, News Corp. made headlines when it bought Utarget, a European ad network that specializes in online video, for an undisclosed sum.

Cox is believed to have spent $300 million in cash for Adify.