Verizon Shakes Up the IXCs. And although the services are based on the same technology, the rush to bring them to market has actually left them incompatible. He adds that his company is testing future phones for interoperability with other networks in Europe and Asia, including Japan. Such systems all use the same frequencies and the same basic specification, published by the 3G Partnership Project , so global roaming should eventually be possible.
Coverage is another mutual weakness.
NTT DoCoMO will initially offer its service only in a few select Tokyo neighborhoods, though expansion to other Japanese cities is planned within a year. For comparison, a typical European country would need at least 1,000. The higher frequencies necessary for 3G mean that cells are smaller, so existing 2G infrastructure often cannot be reused. Problems aside, Manx Telecom and NTT DoCoMo are still years ahead of everyone else. The bear market in tech stocks has also made 3G network funding difficult, and some hope to save money by sharing cell sites and the fiber that links them together.