Nortel Networks Corporation, formerly known as Northern Telecom Limited and sometimes known simply as Nortel, was a multinational telecommunications equipment manufacturer headquartered in Mississauga, Ontario, Canada.

On January 14, 2009, Nortel filed for protection from its creditors in the United States, Canada, and the United Kingdom, in order to restructure its debt and financial obligations. In June 2009, the company announced it would cease operations and sell off all of its business units. The period of bankruptcy protection has since been extended to April 13, 2012. As part of the bankruptcy proceedings, Nortel Networks Inc. publishes monthly operating reports outlining cash receipts and disbursements.

In 1882, a mechanical department was created within Bell Telephone Company of Canada to manufacture telephones and telephone equipment for Canada, due to restrictions on importing telephone equipment from the United States. In addition to phones, four years later, the department started manufacturing its first switchboard, a 50 line Standard Magneto Switchboard. The small manufacturing department expanded yearly with the growth and popularity of the telephone to 50 employees in 1888. By 1890 it had transformed into its own branch of operations with 200 employees, and a new factory was under construction.