The online service, which has trailed rival America Online in embracing the high-speed Net world, will kick off trials of broadband Internet access in four cities on Monday.
The consumer offering will use digital subscriber line technology. DSL allows existing phone lines to be upgraded to handle high-speed Internet traffic and phone service simultaneously.
Microsoft's move underlines its growing support for DSL after years of investing in cable services such as Comcast and Road Runner, which compete with telephone companies for consumers' high-speed Internet business.
Despite the several hundreds of millions of dollars invested in cable companies, cable networks are still closed to the Microsoft Network service. But Microsoft is a minority stakeholder in Road Runner, the high-speed Net service controlled by Time Warner cable and MediaOne.
The software giant began its move towards the DSL camp last week, taking a small stake in Rhythms NetConnections, a DSL provider that competes with the big local telephone companies. Microsoft Network also is creating a series of co-branded broadband portal pages for Rhythms' business customers.
The four new trials, which will start in Seattle and Atlanta and then move to Chicago and San Diego, will be MSN's first broadband consumer offering. The company said it would roll out the service to at least 20 cities by the fall of 1999.
If the company is able to keep to this schedule, it will be close on the heels of America Online, which has already struck deals with Bell Atlantic and SBC Communications to offer broadband AOL over the telcos' DSL lines. Those deals, which will also be available to consumers this fall, will offer high-speed America Online service at about $42 a month.
No pricing information was immediately available for the high-speed MSN service.