AT&T Corp is closing its AT&T Business Network Web site, which offers a wide variety of business information, Nets Inc, the Internet company that ran it under license from AT&T said. The site remained active on Monday, but was no longer being updated on a daily basis, and is set to close by the beginning of April. It will cost 54 of the 304 Nets employees their jobs. Nets was formed by AT&T with Industry.Net Inc, the company led by Jim Manzi.