John Donovan, the top telecom exec at AT&T, said he will retire October 1. The carrier said it will name a replacement for Donovan "soon."

For the past two years, Donovan has been the CEO of "AT&T Communications," one of the four divisions within AT&T. The operator's other divisions are its Latin American business under Lori Lee; the advertising and analytics business called Xandr under Brian Lesser; and WarnerMedia under John Stankey that houses AT&T's new entertainment businesses that stretch from HBO to DirecTV. All those divisions report to AT&T CEO Randall Stephenson.

Donovan's responsibilities at "AT&T Communications" range across the operator's fiber, wireless and TV networks and cover 100 million mobile, broadband and pay-TV customers.

Both Donovan and Stephenson offered upbeat statements on Donovan's departure.

"It's been my honor to lead AT&T Communications during a period of unprecedented innovation and investment in new technology that is revolutionizing how people connect with their worlds," Donovan said in a statement. "I'm looking forward to the future -- spending more time with my family and watching with pride as the AT&T team continues to set the pace for the industry."

"JD is a terrific leader and a tech visionary who helped drive AT&T's leadership in connecting customers, from our 5G, fiber and FirstNet buildouts, to new products and platforms, to setting the global standard for software-defined networks," Stephenson said in a statement. "JD is a good friend, and I wish him and his family all the best in the years ahead."

Despite the rosy comments, it's unclear whether Donovan is leaving of his own accord. On one hand, the business he is leaving remains a bright spot in AT&T's overall financial situation. As the Wall Street analysts at MoffettNathanson noted, mobility remains AT&T's largest business, accounting for 39% of its consolidated revenues, and the operation continues to turn in increasingly solid financial results. That stands in stark contrast with AT&T's other divisions, including WarnerMedia, which continues to struggle with subscriber losses and a constantly shifting video-delivery strategy.

On the other hand, according to Reuters Donovan is 58 -- the same age as Stephenson -- and so he may be unwilling to spend any more time in a position from which he likely won't advance.

Donovan joined AT&T in 2008 as chief technology officer, previously having worked at companies including Verisign and InCode Telecom Group. At AT&T Donovan gained global visibility in driving AT&T's push toward software-defined networking and network function virtualization. His leadership in the area crystallized with AT&T's announcement in 2014 that AT&T would virtualize 75% of its network operations by 2020.

Donovan also spearheaded AT&T's push into 5G -- including the company's acquisition of millimeter-wave spectrum in FCC auctions, the purchase of FiberTower and its deal with FirstNet for a nationwide wireless network for public-safety communications.

Donovan was promoted to AT&T's Chief Strategy Officer and Group President of AT&T Technology and Operations before being named CEO of AT&T Communications in July 2017, when AT&T reorganized following its acquisition of Time Warner.

— Mike Dano, Editorial Director, 5G & Mobile Strategies, Light Reading | @mikeddano