In this paper, we consider two fairness problems that occur in the infrastructure network (fairness between TCP uplink/downlink flows and fairness between competing TCP uplink flows). A large number of existing works have studied the TCP fairness issues and greatly solved the TCP unfairness problems. However, these solutions suffer from the drawback of TCP… (More)
Vertical handover is to change the local interface or the access network of mobile node in the middle of communications. IEEE 802.21 Media Independent Handover (MIH) model can provides mobile nodes with necessary information for handover. This paper proposes a MIH vertical handover model which is consists of event messages, vertical handover procedure, and… (More)
Pastry is applied to multicast the real-time data and PAST in Pastry is used to store and provide the past data. Also as Pastry itself does not provide the search function, we propose to use PAST for providing search function using keywords.
The saw-tooth like behaviors of TCP impact Assured Forwarding Service flows in a differentiated services (diffserv) network. Therefore, we argue the use of TCP-friendly building blocks (or modules) and fairness modules in the diff-serv architecture regarding this issue, and propose Two Markers System (TMS) that is able to properly mark packets and fairly… (More)
Assured Service, a service model of Internet Differentiated Services (DiffServ) architecture, is not so well accommodated by the current Internet environment. This is because the Internet's Transmission Control Protocol (TCP) employs an AIMD (Additive Increase and Multiplicative Decrease) mechanism to control congestion. As a result, Assured Service cannot… (More)
There are two cruxes of issues identified in differentiated services (diffserv) networks: One is TCP dynamics over Assured Services, and the other is the interaction of TCP and UDP flows for Assured Forwarding Per Hop Behavior (PHB). Therefore, we argue unfair distribution of excess bandwidth in an over-provisioned networks as well as unfair degradation in… (More)