Bay Networks, Inc., was a network hardware vendor formed through the merger of Santa Clara, California, based SynOptics Communications and Billerica, Massachusetts based Wellfleet Communications on July 6, 1994.

In December 2009, as part of its bankruptcy proceedings, Nortel sold its Enterprise Networking equipment and software business to Avaya.

The sale included a few remaining Bay Networks products that were still active in Nortel's portfolio at the time of the sale, such as the Ethernet Switch 450 and Backbone Concentrator Node (BCN) router.

Example products include Gigabit Ethernet switches, cable modems, print servers, and similar inexpensive, consumer-oriented networking equipment.

Bay Networks had originally launched Netgear as a product line/division in January 1996, but the product line was not core to the newly formed Nortel Networks operations and so was spun out as a standalone company in September 1999.