• The KIPS Transactions:PartC
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• v.9C no.5
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• pp.783-788
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• 2002

Adaptive Cyclic Packet Dropping algorithm (ACPD), and Non-adaptive Cyclic Packet Dropping algorithm (NCPD) are applying stricter drop precedence than that of RIO algorithm. Especially, the ACPD algorithm drops adaptively packets for the congestion control, as predicting traffic pattern between each cycle. Therefore the ACPD algorithm makes up for the drawback of RIO algorithm and minimizes the wastes of the bandwidth being capable of predicting in the NCPD algorithm. And we executed a simulation and analyzed the throughput and packet drop rate based on Sending Priority changing dynamically depending on network traffic. In this algorithm, applying strict drop precedence policy, we get better performance on priority levels. The results show that the proposed algorithms may provide more efficient and stricter drop precedence policy as compared to RIO independent of traffic load. The ACPD algorithm can provide better performance on priority levels and keep stricter drop policy than RIO and the NCPD algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.4B
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• pp.399-404
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• 2011

For the underwater wireless sensor networks, we propose the packet transmission method which distinguishes more important packet than others. Because the ocean underwater transmission environments are extremely unstable, we use SON(Self Organizing Network) techniques to adapt to the constantly varying underwater acoustic communication channels and randomly deployed sensor nodes. Especially we suppose two kinds of packets which have different priorities, and through the simulations we show that high priority packets arrive at the source node faster than lower priority packets with a proposed scheme.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.469-472
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• 2014

S-MAC is hybrids of CSMA and TDMA approaches that use local sleep-wake schedules to coordinate packet exchanges and reduce idle listening. In this method, all the nodes are considered with equal priority which may lead to increased delay during heavy traffic. The method introduced in this paper provides high throughput and small end-to-end delay suitable for applications such as real-time voice streaming and its functionality is independent of underlying synchronization protocol. The novel idea behind our scheme is that it uses the priority concept with (m,k)-firm scheduling in order to achieve its objectives. The performance of our scheme is obtained through simulations for various packet sizes, traffic loads which show significant improvements in packet delivery ratio, and delay compared to existing protocols.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11S
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• pp.3251-3259
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• 1999

In this paper, we present a new mechanism applying more strict priority than RIO mechanism proposed as a drop precedence policy of AF classes in differentiated services. In this mechanism, applying strict priority to drop precedence policy, we get better performance on priority level. Simulation results indicate that the proposed mechanism may provide more efficient and more strict priority transmissions as compared to RIO regardless of traffic load.

• Journal of applied mathematics & informatics
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• v.22 no.1_2
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• pp.453-460
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• 2006

A discrete-time priority queueing system with place reservation discipline is studied, in which two different types of packets arrive according to batch geometric streams. It is assumed that there is a reserved place in the queue. Whenever a high-priority packet enters the queue, it will seize the reserved place and make a new reservation at the end of the queue. Low-priority arrivals take place at the end of the queue in the usual way. Using the probability generating function method, the joint distribution of system state and the delay distribution for each type are obtained.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.1
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• pp.32-43
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• 2000

In this paper, we investigate the existing medium access control (MAC) protocols to integrate the voice and data services in packet-based CDMA networks and furthermore, propose a new approach to circumvent the operational limits inherent in them. We propose the $P^2R$-CDMA (Prioritized Packet Reservation Code Division Multiple Access) protocol for the uplink in the synchronous multi-code CDMA system, which employs the centralized frame-based slot reservation along with the dynamic slot assignment in the base station using the QoS-oriented dynamic priority of individual terminal. The simulation results show that, as compared with the existing scheme based on the adaptive permission probability control (APC), the proposed approach can significantly improve the system capacity while guaranteeing the real-time requirement of voice service.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.11
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• pp.2124-2126
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• 2008

In the wireless communication systems, the demand of multimedia services is also increased. Unlike typical data packets, realtime service such as VoIP packets have delay bound and low loss rate requirement. In this paper we propose a new scheduling algorithm that be able to allocate resources to the different kinds of services such as VoIP and data packet. The proposed algorithm considers both time delay and channel condition toe determine the priority. Simulation results show that the proposed algorithm works more efficiently than the conventional algorithms.

• Journal of KIISE:Information Networking
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• v.31 no.1
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• pp.1-10
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• 2004

This study discusses Application-layer FEC using erasure codes. Because of the simple decoding process, erasure codes are used effectively in Application-layer FEC to deal with Packet-level errors. The large number of parity packets makes the loss rate to be small, but causes the network congestion to be worse. Thus, a redundancy control algorithm that can adjust the number of parity packets depending on network conditions is necessary. In addition, it is natural that high-priority frames such as I frames should produce more parity packets than low-priority frames such as P and B frames. In this paper, we propose a redundancy control algorithm that can adjust the amount of redundancy depending on the network conditions and depending on data priority, and test the performance in simple links and congestion links.

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

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.4
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• pp.812-822
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• 1997

In this paper, we propose an architecture of the asynchronous shared-bus type switch with priority and fairness schemes. The switch architecture is an input and output queueing system, and the priority scheme is implemented in both input and output queues. We analyze packet delay of both input and output queues. In the analysis, we consider to stations with asymmetric arrival rates. Although we make some approximations in the analysis, the numerical results show good agreements with the simulation results.