• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.6
• /
• pp.2922-2945
• /
• 2018

Achieving efficient authentication is a crucial issue for stream data commonly seen in content delivery, peer-to-peer, and multicast/broadcast networks. Stream authentication mechanisms need to be operated efficiently at both sender-side and receiver-side at the same time because of the properties of stream data such as real-time and delay-sensitivity. Until now, many stream authentication mechanisms have been proposed, but they are not efficient enough to be used in stream applications where the efficiency for sender and receiver sides are required simultaneously since most of them could achieve one of either sender-side and receiver-side efficiency. In this paper, we propose an efficient stream authentication mechanism, so called TIM, by integrating Trapdoor Hash Function and Merkle Hash Tree. Our construction can support efficient streaming data processing at both sender-side and receiver-side at the same time differently from previously proposed other schemes. Through theoretical and experimental analysis, we show that TIM can provide enhanced performance at both sender and receiver sides compared with existing mechanisms. Furthermore, TIM provides an important feature for streaming authentication, the resilience against transmission loss, since each data block can be verified with authentication information contained in itself.

• Journal of the Korean Society for Precision Engineering
• /
• v.18 no.6
• /
• pp.121-126
• /
• 2001

Currently, potentiometric method has been employed to measure fuel amount for automobile. However, potentiometer could be malfunctioned or damaged due to the additives or dirt in fuel because a variable electric resistor is immersed in fuel. Therefore, a device employing strain sensor is designed and tested to verify the possibility as an alternative of the conventional fuel sender. Existing fuel tank has irregular cross section. Therefore, buoyancy is not increased linearly as fuel amount is increased. We design a floater that can compensate the irregular cross section of fuel tank and make buoyancy to increase linearly with increasing fuel amount. New fuel sender, comprising of strain gages on circular membrane, the above commented floater and the cover to prevent the disturbance due to sudden acceleration and deceleration, is designed and tested to replace current fuel sender. On the other hand, we are developing strain sensor that has strain gage deposited directly on the circular membrane with cantilever beam.

• Journal of Digital Contents Society
• /
• v.15 no.4
• /
• pp.547-558
• /
• 2014

Recently, in the course of business processes a variety of abuse cases of fax documents is common in general corporate, government, and financial institutions. To solve this problem, it is necessary for a technique to prevent falsification of fax documents. In this paper, we propose a new fax sender verification technique based on pattern analysis to prevent falsification of fax documents only using the received fax document. In the proposed technique, the fax sender is verified by analyzing the communication signal patterns between the fax sender and receiver and image pattern in the received fax document. In this paper, we conduct the experiments that apply our technique to real-world fax systems, and then tamper-proof effects were confirmed from the experimental results.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 1987.04a
• /
• pp.86-92
• /
• 1987

We implement an universal signaling equipment including many kinds of singling devices just as R2 MFC seder.receiver DTMF sender/receiver Tone sender sued in Digital Switching System the universal signaling equipment has two parts sender part and receiver part. The sender part is implemnted with ROM-LOOK-UP Table method and the receiver part is implemnted that the equipment satisfies the Recomandations of CCITT. Also the capability of the equipment is evaluated by the LCS(Local Call Simulatior)Test in the TDX-1A system.

• International Journal of Contents
• /
• v.4 no.2
• /
• pp.13-18
• /
• 2008

A load sharing algorithm is one of the important factors in computer system. In sender-initiated load sharing algorithms, when a distributed system becomes to heavy system load, it is difficult to find a suitable receiver because most processors have additional tasks to send. The sender continues to send unnecessary request messages for load transfer until a receiver is found while the system load is heavy. Because of these unnecessary request messages it results in inefficient communications, low cpu utilization, and low system throughput. To solve these problems, we propose a self-adjusting evolutionary algorithm for improved sender-initiated load sharing in distributed systems. This algorithm decreases response time and increases acceptance rate. Compared with the conventional sender-initiated load sharing algorithms, we show that the proposed algorithm performs better.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2001.05a
• /
• pp.388-394
• /
• 2001

In this paper, a large number of algorithm have been proposed for error concealment and reconstruction real-time voice transmission for over the internet. The main purpose of this algorithm perform error reconstruction using low bandwidth and then guarantee good voice quality. Error concealment algorithm can be classified into receiver-based and sender- and receiver-based. In this paper, we apply the sender - and receiver-based reconstruction algorithm to low bit rate codec using CELP.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.2
• /
• pp.396-407
• /
• 1999

A Multicast transfer is a critical delivery method to provide a transport service to multipeer applications, the various problems on the multicast transfer environments have been occurred from the results of current research. One of these problems is the multicast transport service issue to guarantee reliability and scalability. First, this paper presents the related research of the reliable multicast transport methods, and then proposes a new transfer architecture using the Agent Sender and Receiver Concept(ASRC) to solve a reliable multicast transfer issue. we also propose a method to apply the proposed architecture(ASRC) to the well-known sender-initiated and receiver-initiated transport protocol. In order 새 validate the proposed ASRC architecture, t도 applied sender and receiver system si compared and analyzed over the processing requirement and maximum throughput.

• The KIPS Transactions:PartC
• /
• v.11C no.5
• /
• pp.689-696
• /
• 2004

The conventional email method based on a recipient mailbox has a structural weakness, which may cause the spam message problem and the extreme waste of recipient mailbox space, and also require an explicit recipient notification scheme. This paper proposes a new email method based on a sender mailbox and evaluates its performance. Under the new email method, a message is stored at sender mailbox instead of recipient one until an intended recipient reads the message, so that the burden of mailbox management such as removing spam message is now shifted to sender side. And also a sender can confirm whether an intended recipient has read his or her message by simply rummaging his or her sender mailbox. The results of Performance evaluation show that 75% of mailbox space and 90% of message traffic are reduced in conditions that the portions of spam message and multicasting message are 90% and 80%, respectively.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.3
• /
• pp.755-761
• /
• 2013

Medium access control (MAC) protocols for wireless sensor networks make sensor nodes on state for energy-efficiency only when necessary. In this paper we present an energy efficient priority-based MAC protocol for energy-harvesting Wireless Sensor Networks (WSNs). For support priority-based packet transmission the proposed EEPB-MAC protocol uses the modified IEEE 802.15.4 beacon frames including priority bit, sender node address, and NAV value fields. A receiver node periodically wakes up, receives sender beacon frames, selects data sending sender, and broadcasts a beacon frame containing the selected sender's address. A receiver node selects sender node according to sender's data priority. A receiver nodes also adjust wake up period based on their energy states. Hence, the energy consumption of receiver node can be minimized. Through simulations and analytical analysis, we evaluate the performance of our proposed the EEPB-MAC protocol and compare it against the previous MACs. Results have shown that our protocol outperforms other MAC in terms of energy consumption, higher priority packet delivery delay.

• Journal of Korea Multimedia Society
• /
• v.8 no.12
• /
• pp.1613-1622
• /
• 2005

Broadcasting is fundamental and effective data dissemination mechanism for route discovery, address resolution, and many other network services in mobile ad hoc networks. Although many approaches for broadcasting have been proposed to minimize the number of retransmissions, none of them guarantee the best-suited bounds of retransmissions. Appropriate use of probabilistic method can lower the chance of contention and collision among neighboring nodes, so that it reduces the number of rebroadcasts. In this paper, we propose a probabilistic approach that dynamically adjusts the rebroadcasting probability according to the distance between the sender and the receiver. While the rebroadcast probabilities of a mobile node close to sender will be set lower, the rebroadcast probabilities of a mobile node far away from sender wi1l be set to higher, The rebroadcast probability of a node wi1l be set according to the distance from sender. We evaluate the performance of proposed approach by comparing it with flooding as well as a fixed probabilistic broadcast approach. Simulation results showed that the performance of proposed scheme outperforms by about $70\%$ than flooding scheme and outperforms by about $20\%$ than fixed probabilistic scheme.