SINGAPORE -- Designed to even the global playing field, the Information Technology Agreement signed in December by 28 member countries of the World Trade Organization removes tariffs on many high-tech products, which should result in major gains for countries that export them -- if everybody plays fair.The agreement phases out tariffs on many high-tech products including fiber optic cable, but not optical fibers, by the year 2000. Among other products covered are optical disk storage units, flat-panel displays, network equipment and computers.As designed, the agreement will reduce prices of high-tech equipment, making it more accessible to lesser- developed countries. At present, US government officials say high tariffs in countries such as India preclude consumers from purchasing many types of equipment not available in their domestic markets."To say [fiber optic cable sales] are immediately going to jump into the billions is a stretch, but clearly we're talking in the hundreds of millions," said Tim Regan, vice president in charge of public policy for Corning. One of the world's largest producers of optical fiber, Corning annually sells $500 million worth of fiber cable.But there's a hitch. Despite the agreement, industry experts have expressed concern that nontariff barriers will keep the competitive edge with domestic companies. "Will [governments and postal telephone and telegraph companies] procure in a way that is not favorable to their own industries?" Regan asked. "Can you get certified quickly, or will you have to wait? Will import licenses be issued quickly, or will they be murder to get? We're reasonably optimistic they will."Participants in the agreement include the US, the European Union, Japan, Korea, Taiwan, Canada and Singapore.