Sony has become the latest player to line up broadband partners in Japan. Close on the heels of the announced partnership of AT&T and Microsoft affiliated cable provider in Japan, Sony has announced that it will team with Tokyu Cable Television to jointly develop a high-speed broadband network in Japan. Sony has taken a 10 percent stake in Tokyu as part of the deal, with the option to increase its investment in the future. The companies hope to add more cable providers to the partnership.