Research Publications Authored by SLIIT Staff
Permanent URI for this communityhttps://rda.sliit.lk/handle/123456789/4195
This collection includes all SLIIT staff publications presented at external conferences and published in external journals. The materials are organized by faculty to facilitate easy retrieval.
Browse
2 results
Filters
Advanced Search
Filter by
Settings
Search Results
Publication Open Access Modeling of router-based request redirection for content distribution network(Foundation of Computer Science, 2013-01-01) Harahap, E; Wijekoon, J; Tennekoon, R; Yamaguchi, F; Ishida, S; Nishi, HThe increase of digital data between content’s servers and clients in a network causes congestion problems when downloading big web contents including files, streaming media, etc. The problem becomes pronounced when a narrow bandwidth or unexpected termination of streaming services is appeared. Content Delivery Network (CDN) is introduced to overcome such problems by redirect client’s request to the best server which proximal and least loaded. However, with intensity increase of people accessing a particular content, the performance of CDN is reduced and sometimes congested. We propose an architecture to solve such problems with a new method to redirect client’s request through a special router called Service-oriented Router (SoR). In this paper, several analytical studies and experiments have been conducted and the result show that router-based redirection is more effective than DNS-based redirection that is currently being used. SoR has been introduces as a content-based router and has capability to do deep packet inspection (DPI) into the packet streams and analyze them. We use SoR in our proposed method as a CDN’s core-router to redirect client’s request to the best server. Our experiment conducted with model and numerical analytic supported by optimal redirection probability based on delay between router and server. The experiment result confirmed that the router-based redirection reduced the response time by 23.3% compared to the DNSbased redirection.Publication Open Access Flood modeling in the Mahaweli River reach from Kothmale to Polgolla(University of Peradeniya, 2007) Rathnayake, U. S; Weerakoon, S. B; Nandalal, K. D. W; Rathnayake, UThe occurrence of floods and inundation of the low lands adjacent to the Mahaweli River reach from Gampola to Polgolla were very frequent prior to the Kotmale reservoir project in mid 1980s. However, during last two decades with the construction of the Kotmale dam, the regulation of flow by the reservoir has reduced the inundation risk of these lands, which were vulnerable to frequent flooding. As a result, these lands are developed at an increasing rate and more people have started to live in them. This fact gives an alarming signal to the authorities, as the damage that might be caused due to an extreme flood event could be significant. It is therefore of paramount importance that comprehensive flood modeling and inundation analysis of the Mahaweli River reach between Kotmale and Polgolla is carried out. This paper presents the flood modeling and inundation analysis in the Mahaweli river reach from the Kotmale dam to Polgolla barrage using the HECRAS model. The HECRAS model was set up for the river reach using the river cross-sections at 200 m intervals from Kotmale dam to Polgolla barrage. The model was applied to estimate the water stages along the river reach for the floods of different return periods. Though the Kotmale reservoir acts as a flood control reservoir for floods of medium return periods, it becomes ineffective to reduce the flood levels in the downstream flood plains due to floods of high return periods when it has to release high discharge. Inundation areas in the downstream of the dam due to several flood discharges are presented.