Cisco Systems is laying off at least 14,000 employees, around 20 percent of its total workforce, technology news site CRN reported Tuesday.

Sources told CRN that the San Jose-based company will announce the layoffs within the next few weeks. The manufacturer of networking equipment will dismiss between 9,000 to 14,000 employees worldwide as it transitions from “its hardware roots into a software-centric organization,” the report said. Many employees have already been offered early retirement plans.

“They need different skill sets for the software-defined future than they used to have,” a source said. “In theory the addressable market could be higher and margins richer, but it will take some time to make this transition.”

Cisco, as of April 2016, boasted of 73,104 employees. This 20 percent slash would be the single largest layoff in the company’s 20-year history. However, this isn’t the first time Cisco has announced massive layoffs. The company in August 2014 said that it planned to slash 6,000 jobs. In August 2013, Cisco dismissed 4,000 employees. One of Cisco’s largest layoffs came in July 2011 when the company fired 6,500 employees.

Cisco isn’t the only tech giant undergoing changes. Microsoft Corp reportedly indulged in one of the largest layoffs in tech history when it dismissed 18,000 employees in July 2015. HP Inc announced in September 2015 that it will lay off 33,300 jobs over three years. Intel in April said that it will cut 11 percent of its global workforce.