Margaret Chiosi, one of the most prominent service provider voices in software-defined networking (SDN) and network functions virtualization (NFV), has retired from AT&T.

Chiosi was a distinguished network architect at the carrier.

“Margaret retired on May 16 after 39 years of service at AT&T,” wrote a company spokesperson in an email to SDxCentral. “She didn’t indicate her future plans, but we wish her the best of luck.”

Chiosi has been a regular spokeswoman for AT&T’s Domain 2.0 initiative, and she has been very active in open source groups such as the OpenDaylight Project (ODL) and OPNFV.

Marc Cohn, vice president, network strategy, for the Linux Foundation, says:

Margaret was instrumental in the formation and guidance of the ETSI NFV ISG from the very beginning. Although she did not hold a formal leadership position, she was as influential as any in launching one of the industry's most innovative and impactful industry groups, setting the stage for what NFV has evolved into today. Her commitment, conviction, and passion will be sorely missed, but she will continue to exert her leadership on OPNFV. 

AT&T is making a lot of moves in virtualization, lately. Earlier this week, Ralph de la Vega, vice chairman of AT&T Business Solutions and AT&T International, said the company is going to launch a global service using SDN that will hit 63 countries at the same time on the same day.

By the end of 2016, AT&T expects to have 105 data centers in its integrated cloud, which serves as the basis for its virtualization strategy.

And the company has created its own comprehensive virtualization strategy – Enhanced Control, Orchestration, Management, and Policy (Ecomp) – which it’s pitching out to open source groups for feedback.