| Mikio Kuwahara | Network Systems Research Dept., Central Research Lab., |
| Masashi Yano | Network Systems Research Dept., Central Research Lab., |
| Kiyoshi Kawamoto | CDMA Development Dept., |
| Masahiro Takatori | CDMA Development Dept., |
In the field of mobile communication networks, services apart from voice (such as e-mail, Internet access, and music downloading) are expanding. As a result, "all-IP networks" — which can also provide voicecommunication services on a network based on IPs— are being established. Research and development, as well as standardization activities concerning these all-IP networks, are therefore being pushed forward. Hitachi is investigating various capabilities required for transmission of voice on "all-IP-based mobile networks." One of these investigations involves testing on an EV-DO-standard test system implemented with a QoS function for averting increases in delay in voice transmissions.
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The Hitachi Hyoron (Japanese Only) |
1xEV-DO, VoIP, MMD
