Arbor Networks is a software company founded in 2000 and based in Burlington, Massachusetts, United States, which sells network security and network monitoring software, used – according to the companys claims – by over 90% of all Internet service providers. The companys products are used to protect networks from denial-of-service attacks, botnets, computer worms, and efforts to disable network routers. The company was founded in 2000 when founders Farnam Jahanian and Rob Malan spun out research from the University of Michigan. They were joined by students Jonathan Arnold, Matthew Smart, and Jonathan Poland to make the founding team. The company raised $11 million in a round of venture capital. Later, in August 2002, the company raised another $22 million in a second round of venture capital, led by Thomas Weisel Venture Partners, with participants that included Battery Ventures and Cisco Systems, among others. In January 2008, Arbor acquired Ellacoya Networks, a company which provides broadband traffic shaping products. The acquisition was expected to increase the total addressable market (TAM) for Arbor to $750 million in 2008, and to $1.5 billion by the end of 2009. In March 2009, Arbor worked with 100 ISPs to create a new network monitoring system, called ATLAS 2.0. In October 2009, the company estimated that Google paid almost nothing for YouTubes bandwidth, noting that Google probably used dark fibre instead to run the website. On August 31, 2010, Tektronix Communications announced that it has completed its acquisition of Arbor Networks. Upon completion of the acquisition, Arbor Networks joins Danaher Corporations portfolio of communications and enterprise companies, which includes Tektronix Communications.