His resignation comes after four tumultuous years at the helm of the struggling network equipment maker.
The struggling network equipment maker will cut its workforce by about 14 percent in an effort to trim $1 billion in costs, European newspapers report.
The world's largest telecom service providers and equipment suppliers want "smart" cloud-based networks, free of regulations, that offer services rather than "dumb" pipes for connectivity.
Former aerospace executive Philippe Camus, and Ben Verwaayen, former head of BT Group, will take top spots at the troubled company, The Wall Street Journal says.
Mobile-app developers say a proposed AT&T plan that would allow some apps to pay for a 1-800-like service to provide consumers with free data access could hobble innovation.