The telephony subsidiary of a rather shadowy Omaha, Nebraska company has stolen a march on the Baby Bells in the field of Metropolitan Area Networks. Oakbrook Terrace, Illinois-based Metropolitan Fiber Systems Inc, which has fibre loops laid in New York, Chicago, Los Angeles, Philadelphia, Boston, Houston, Dallas, San Francisco, Pittsburgh, Minneapolis and Baltimore, says that it has now begun 100Mbps service in Houston on what it says is the first metropolitan ultra-high-speed data network. The Baby Bells are planning to introduce comparable Synchronous Optical Network and Switched Multimegabit data Service over the next two or three years. Metropolitan Fiber, which charges from $500 a month for the service, plans to introduce it in its other 10 cities over the next year. It has 250 employees, and is owned by privately-held Peter Kiewit Sons Inc of Omaha, which does not disclose its financial figures.