Browsing by Author "Lin, Feng-Yi"

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A Dynamic Security Traversal Mechanism for Providing Deterministic Delay Guarantee in SDN
(2014-01-01)
Chen, Yu-Jia
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Lin, Feng-Yi
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Wang, Li-Chun
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Lin, Bao-Shuh
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電機資訊學士班
For security concerns, a security traversal service can route data flows through a sequences of security devices (middleboxes). In this paper, we identify the problem of delay guarantee in security traversal and propose a scheme to dynamically change the security traversal path. To provide deterministic delay guarantee with minimum virtual machine (VM) and transmission cost, we model this security traversal path determination as a constrained shortest path problem (CSP) and propose an optimal security traversal with middlebox addition (OSTMA) mechanism. Besides, we implement the proposed OSTMA mechanism in an Open Flow network by designing a centralized security traversal controller to dynamically monitor the network condition information and reconfigure the security traversal path. Our experimental results show that the proposed dynamic security traversal scheme can still achieve delay requirements for network topology changes and burst traffic.
Deterministic Quality of Service Guarantee for Dynamic Service Chaining in Software Defined Networking
(2017-12-01)
Chen, Yu-Jia
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Wang, Li-Chun
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Lin, Feng-Yi
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Lin, Bao-Shuh Paul
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交大名義發表
In this paper, we present a systemic approach to provide deterministic delay guarantee for dynamic service chaining in software defined networking (SDN). The delay performance of service chaining in SDN is affected by signaling message exchange in control plane and packet transmissions in data plane, respectively. First, we develop an analytical method to characterize the delay performance of control plane when handling traffic with different priorities according to network calculus (NC) and queuing theory. Second, taking into account the estimated delay in control plane, we propose a novel service traversal mechanism to calculate the optimal traversal path for the service chain. We demonstrate that NC delay analysis can provide deterministic quality of service (QoS)-guaranteed service chaining for any specified delay requirements, whereas theoretical queueing delay analysis can only provide statistical QoS guarantee. In summary, the proposed NC delay analysis can help to understand the network design for a future delay sensitive Internet in which deterministic latency must be guaranteed.
Size-dependent strain relaxation in InN islands grown on GaN by metalorganic chemical vapor deposition
(2009-02-09)
Tsai, Wen-Che
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Lin, Feng-Yi
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Ke, Wen-Cheng
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Lu, Shu-Kai
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Cheng, Shun-Jen
We report Raman measurements on InN islands grown on GaN by metalorganic chemical vapor deposition. The Raman frequency of the InN E(2) mode is found to decrease exponentially with the island's aspect ratio, indicating a size dependent strain relaxation during the island formation. Our results suggest that most of the strain at the InN-GaN interface have been released plastically during the initial stage of island formations. After that, the residual strain of only -3.5x10(-3) is further relaxed elastically via surface islanding. The experimental data are in agreement with the strain relaxation predicted from a simplified model analysis as well as three-dimensional finite-element simulations.