PhD, University of Cincinnati, 2016, Engineering and Applied Science: Computer Science and Engineering

Linguistic diversity on the web has stimulated demand for web translation. Online translation services backed by machine translation are able to perform in-place translation on a web page within seconds, giving a web user a general idea of what the web page is about. Nowadays, peer-to-peer applications are adopting Distributed Hash Table (DHT), a serverless approach that distributes loads among all interconnected devices. Kademlia and its variant Mainline DHT have been widely adopted. DHT runs over an overlay network, where interconnected devices as well as keys are assigned node IDs output by a hash function. The value of a key is stored onto one node (or more nodes if needed) whose node ID is the closest to that of the key. Web applications are now in widespread use due to merits of cloud computing, such as cross-platform compatibility and server-centric software maintenance. Node.js unifies server-side and client-side coding and has thrived in recent years. Browserify enables web browsers to exploit existing Node.js modules in the colossal npm repository. WebRTC makes it possible for disparate web browsers to communicate on a real-time basis, paving the way for a browser-based peer-to-peer network where crowdsourced translation can be achieved. Technologies such as bookmarklet, userscript and browser extension empower Internet users to personalize their favorite websites on the fly. The success of Google Translate can be attributed to responsiveness, acceptable accuracy, and integration with web browser. However, Google Translate suffers drawbacks in terms of data privacy, service availability, idiomatic translation, context sensitivity, personalization, minority languages, transliterated text, etc. A DHT-based system for collaborative web translation is proposed to address those drawbacks. Modules of the proposed system include embedded graphical user interface for translation, peer exchanging translation works with its counterparts in an overlay networ (open full item for complete abstract)

Committee: Chia Han Ph.D. (Committee Chair); Fred Annexstein Ph.D. (Committee Member); Anca Ralescu Ph.D. (Committee Member); William Wee Ph.D. (Committee Member); Xuefu Zhou Ph.D. (Committee Member) Subjects: Computer Science

PhD, University of Cincinnati, 2008, Engineering : Computer Science and Engineering

Currently, Peer-to-Peer overlays can be classified into two main categories: unstructured and structured ones. Unstructured overlays are simple, robust, and powerful in keyword search. Structured ones can scale to very large systems in terms of node number and geography, and guarantee to locate an object within O(Log N) hops. However, both of them face difficulties in efficiency and security of overlays. For unstructured ones, the efficiency problem presented is poor scalability. For structured ones, it is long routing latency and enormous overhead on handling system churn. Moreover, both of them are vulnerable to malicious attacks. Peer-to-Peer overlays belong to application-level network. To a great extension, overlay network designs ignore physical characteristics. As the result, their structures are far from underlying physical network or the distribution pattern of overlay peers. These inconsistencies induce system common operations costly, such as routing and lookup. On the other hand, most peers are assumed to have uniform resources and similar behaviors. Thus, Peer-to-Peer protocols were designed to be symmetric. However, in the realistic environment, peers' resources and behaviors are highly skewed. Symmetric protocols actually compromise system performance. Frequently joining and leaving of peers generates enormous traffic. The significant fraction of peers with high latency/low bandwidth links increase lookup latency. Moreover, under the environment without mutual trust, Peer-to-Peer systems are very vulnerable for varied attacks because they lack a practical authentication mechanism. From a different perspective, this dissertation proposes to construct a highly efficient and secure Peer-to-Peer overlay based on the physical network structure of the Internet and network locality of overlay peers. By naturally integrating different network-aware techniques into the Peer-to-Peer overlay, a novel SNSA (Scalable Network Structure Aware) technique has been dev (open full item for complete abstract)

Committee: Dr. Yiming Hu (Advisor) Subjects: Computer Science