Hiroyasu Obata

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Most standard implementations of congestion control method perform poorly in the satellite Internet due to both a high bit error rate and a long propagation delay. This paper proposes a new TCP congestion control method called TCP-STAR to improve both TCP performance and adaptability of network conditions over the satellite Internet. The performance and the(More)
The number of wireless Internet service users that use wireless LAN or satellite links has increased. The broadband satellite Internet services have especially attracted attention because of its characteristics such as global coverage and robustness. TCP (Transmission Control Protocol) is used by many typical applications over satellite Internet. However, a(More)
As a variety of communication devices emerging, we can easily install two or more communication interfaces on a PC or a PDA and make a multi-home environment. To utilize this multi-home environment effectively, SCTP (Stream Control Transmission Protocol) has been proposed and standardized. Extending functions of the original SCTP, a strategy which can adapt(More)
Wireless local area networks, based on the distributed coordination function of the IEEE802.11 standard, usually use carrier sense multiple access with collision avoidance (CSMA/CA) for media access control. In the CSMA/CA method, if the number of wireless terminals increases, data frame collision often occurs among wireless terminals, which results in a(More)
In wireless LAN environments, the frequency of handover has been increased by the rapid spread of mobile devices such as smartphones and tablets. In such environments, streaming applications such as video feeds, are quite common and have high bandwidth (throughput) requirements. Here, QoS is an important metric for assurance of network quality. QoS-TCP has(More)
Public areas, such as train stations and airports, providing wireless Local Area Network (WLAN) services are increasing and expanding because of the rapid development of WLANs based on IEEE 802.11 standard. Moreover, because of the advances in smartphone tethering technology, portable access points (APs) such as mobile Wi-Fi routers are being utilized more(More)