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Park Chang-Seop;Lee Gyu-Won
- Journal of the Korea Institute of Information Security & Cryptology
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- v.15 no.6
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- pp.71-80
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- 2005
In the near future, various aplications on the Internet will be based on the multicast group communication, so that the efficient group key management is essential for managing the frequent group join and leave events. In this paper, we propose several batch rekeying schemes extended from conventional individual rekeying schemes, and analyze the efficiencies of them in terms of both the number of encryption and one-way hash function as well as multicast message size. Considering multiple member leaves, a probabilistic approach is need to compute the average computational amounts for rekeying.
https://doi.org/10.13089/JKIISC.2005.15.6.71 인용 PDF KSCI HTML

하숙정;이경숙;배인한
- Journal of Korea Multimedia Society
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- v.7 no.3
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- pp.357-367
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- 2004
In VOD systems the number of channels available to a video server is limited since the number of channels, the video server can support, is determined by the communication bandwidth of the video server. Multicast techniques such as batching, patching and batch-patching have been proposed to reduce I/O demand on the video server by sharing multicast data. In this paper, we propose a channel reservation batch-patching technique that first applies the batching technique to hot video requests and then applies the patching technique to the batches of the hot video requests. And the proposed technique reserves a part of the channel capacity of the video server for many hot video requests, so that the hot video requests can be served without defection. The performance of the proposed technique is compared with those of Patching and Batch-Patching techniques in terms of average service latency, defection rate, fairness and frame reduction rate by simulations.
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Chung, Jong-In
- The Journal of Korean Association of Computer Education
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- v.7 no.1
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- pp.55-66
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- 2004
The Internet today provides group communication model, multicast service. It is important to keep security for multicast communication. Member leaving is associated with scalability problem for group key management. If one member of the group is removed, new group key has to be changed and communicated to all remaining members of group. Modification and distribution of new group keys for rekeying is an expensive operation. Minimizing the number of messages and operation cost for generation of the composite keys are important evaluating criteria of multicast key management scheme. Periodic rekey helps reducing these important parameters rather than removing members sequentially in fashion one after another. In this paper, Hamming distance is calculated between every members to be removed. The members with Hamming distance less than threshold are selected for rekeying procedure. With running the round assignment algorithm, our model has advantages of reducing the number of message and operation cost for generation of the composite keys for rekeying.
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Park, Min-ju;Won, Hong-sun
- Journal of the Korea Institute of Information and Communication Engineering
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- v.22 no.6
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- pp.903-909
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- 2018
In December 2017, the world's first LTE-R for 250km/h high-speed railway was commercialized with the opening of Wonju-Gangneung high-speed railway. LTE-R has many advantages such as voice and video call, high-speed data transmission, coverage redundancy and DU redundancy. But it requires efficient use of radio resources because of a limited bandwidth of 10MHz for UL and DL, respectively. The existing unicast scheme has limited high frequency efficiency so when the number of users increases, service is limited due to the network load, which could be a problem for LTE-R in terms of stability and reliability. On the other hand, the multicast scheme via eMBMS can provide stable service even if the number of video users is high. This paper derives the number of unicast scheme users considering the LTE-R network with LAB test and calculation result, and proposes implementation plans and considerations for eMBMS commercialization on LTE-R.
https://doi.org/10.6109/jkiice.2018.22.6.903 인용 PDF KSCI