Conventional flow-monitoring methods, such as sFlow, cannot detect low-rate HTTP GET Flooding denial of service (DoS) attacks, which are a threat even if the traffic rate is low. To solve this problem, we propose a method for detecting DoS attacks on the basis of the burst-state duration of traffic calculated using a quick packet-matching function of a general router such as TCAM. In addition, we prove that the burst-state duration is a good feature for distinguishing a normal user's traffic from a client to a server and low-rate HTTP-GET-Flooding attacker's traffic. Furthermore, we explain the results of an actual equipment evaluation carried out to evaluate the false-negative rate of our method and sFlow in an actual use case. The result shows that the proposed method is superior under the condition that the attack-traffic rate is low. The results also show that the proposed method can reliably detect such attacks under this condition.

In Japan, a terrestrial digital broadcasting service for cellular phone will start for the first time in the world in April, 2006. We already prototyped a cellular phone terminal with terrestrial digital broadcasting function. The evaluation result indicated the need of a quick recovery mechanism for packet loss error of broadcasted data. In addition, an efficient mechanism for developing collaborated applications which fully utilize the both-way communication capability of the broadcasting service with cellular phones as the uplink is expected. However simply transmitting the audience's information (e.g. user account information, channel selection and his/her location) via the cellular phone may cause traffic burden on the cellular network. In this paper we propose a new packet loss recovery mechanism which uses the cellular network for retransmitting the lost packets. Next, we propose a gateway architecture for upload information to reduce the traffic from the terminals to solve the second issue. We demonstrate the effectiveness of these mechanisms through the evaluation using the prototype terminal. We also show the detail implementation of the prototype terminal.

This paper presents a framework for aggregating and updating use activity data (called user profile in this paper) recognized by a cell phone equipped with active RFID transmitter/receiver. Each component of user profile information comes from a different source and is combined each other at the Profile Aggregator (PA), which is user profile management server. In the PA, a piece of information is connected to other related information and this info-linkage facilitates the retrieval of detailed information easily. This function has been implemented based on semantic web technology. The PA has also an important role of privacy control in terms of disseminating a subset of user profile, including a query interface, trigger interface. And we finally describe "Profile Blog," which is a visualization service of aggregated user profile, and a cell phone application called "Remembrance Viewer" through which the past user activities at each location can be seen.

No abstract available.

We discuss the design issues on lightweight and FIPA compliant agent platform for Java-enabled mobile phones and describe the design of such agent platform. This platform changes Java-enabled mobile phones to ubiquitous terminals by providing place for agent applications. Combined with location services, it can be used for various ubiquitous services. We also show the performance comparison of the prototype with LEAP, another lightweight agent platform.

OSI Management model defines only peer to peer communication process between a managing application (AP) and a managed AP. Thus, when more than one managed AP stores portions of Management Information Base (MIB) distributively, the managing AP needs a sophisticated distributed processing function. This paper proposes an agent, called Management System Agent (MSA) which provides location transparency and schema transparency of MIB for managing APs, to ease the realization of managing APs. Location transparency hides the distribution of MIB from managing APs. Schema transparency also enables managing APs to invoke management operation on unified schema. This paper demonstrates the effectiveness of the MSA model through applying it to implementation of Customer Network Management (CNM) system focusing X.25 public data networks.

Results are presented of a study of the feasibility realizing a real-time information retrieval service operating between different worldwide videotex systems by means of gateway facilities that use conversion of data syntax and processing of the videotex information structure. Two separate evaluations were carried out, both using response time as the performance criterion. One was for communication processes at both of two gateways, and the other was for data syntax conversion at the local host. Both approaches are considered as kernel functions in the gateway system. The results of each evaluation were favorable in the sense that response time for the total system using gateways compared favorably to the response time in direct videotex access over the packet-switched public data network.>