The availability of numerous mobile agent systems with its own strengths and weaknesses poses a problem when deciding on a particular mobile agent system. In this dissertation, factors based on mobility, communication and security of the mobile agent systems are presented and used as a means to address this problem. To facilitate in the process of selection, a grouping scheme of the agent system was proposed. Based on this grouping scheme, mobile agent systems with common properties are grouped together and analyzed against the above-mentioned factors. In addition, an application was developed using the Aglet Software Development Toolkit to demonstrate certain features of agent mobility, communication and security. / Theoretical Computing / M. Sc. (Computer Science)

The availability of numerous mobile agent systems with its own strengths and weaknesses poses a problem when deciding on a particular mobile agent system. In this dissertation, factors based on mobility, communication and security of the mobile agent systems are presented and used as a means to address this problem. To facilitate in the process of selection, a grouping scheme of the agent system was proposed. Based on this grouping scheme, mobile agent systems with common properties are grouped together and analyzed against the above-mentioned factors. In addition, an application was developed using the Aglet Software Development Toolkit to demonstrate certain features of agent mobility, communication and security. / Theoretical Computing / M. Sc. (Computer Science)

<p>У дисертацији је представљен прототип агентског, домен-оријентисаног језика ALAS. Основни мотиви развоја ALAS језика су подршка дистрибуираном не-аксиоматском резоновању као и омогућавање интероперабилности и хетерогене мобилности Siebog агената јер је приликом анализе постојећих агентских домен-оријентисаних језика утврђено да ни један језик не подржава ове захтеве. Побољшање у односу на сличне постојеће агентске, домен-оријентисане језике огледа се и у програмским конструктима које нуди ALAS језик а чија је основна сврха писање концизних агената који се извршавају у специфичним доменима.</p> / <p>U disertaciji je predstavljen prototip agentskog, domen-orijentisanog jezika ALAS. Osnovni motivi razvoja ALAS jezika su podrška distribuiranom ne-aksiomatskom rezonovanju kao i omogućavanje interoperabilnosti i heterogene mobilnosti Siebog agenata jer je prilikom analize postojećih agentskih domen-orijentisanih jezika utvrđeno da ni jedan jezik ne podržava ove zahteve. Poboljšanje u odnosu na slične postojeće agentske, domen-orijentisane jezike ogleda se i u programskim konstruktima koje nudi ALAS jezik a čija je osnovna svrha pisanje konciznih agenata koji se izvršavaju u specifičnim domenima.</p> / <p>The dissertation presents the prototype of an agent-oriented, domainspecific<br />language ALAS. The basic motives for the development of the<br />ALAS language are support for distributed non-axiomatic reasoning, as well<br />as enabling the interoperability and heterogeneous mobility of agents,<br />because it is concluded by analysing existing agent-oriented, domainspecific<br />languages, that there is no language that supports these<br />requirements. The improvement compared to similar existing agentoriented,<br />domain-specific languages are also reflected in program<br />constructs offered by ALAS language, whose the main purpose is to enable<br />writing the concise agents that are executed in specific domains.</p>

本論文研究在於一行動計算網路上建構一個具有服務品質保障之以代理人為基礎的服務系統以提供用戶及行動代理人的行動能力管理。此研究主要的貢獻可分為以下三方面： (1) 提出行動能力管理機制，使行動用戶能以單一用戶ID漫遊於不同的網路上 (2) 提出行動代理人行動能力管理機制，幫助系統搜尋一已派遣出之代理人以加強對代理人的管理 (3) 提出一個「以代理人 (Agent) 為基礎之有服務品質 (QoS) 保障的管理架構」以支援行動代理人及行動用戶之行動能力的管理，並確保服務品質 在本論文中，我們將探討如下的研究課題： (1) 對行動用戶之行動能力的管理 (A) 多個廣域網路管理中心架構 (B) 用戶行動能力與網路通訊時間之分析 (C) 訂定欲註冊之GNMC、LNMC選擇策略 (D) 行動用戶移動時的註冊及註銷策略 (E) 對行動用戶之位置的定位及追蹤 (F) 使用暫存器記錄以提昇用戶位置追蹤的效率 (2) 對行動代理人之管理 (A) 對行動代理人之多種搜尋策略 (B) 於每次搜尋時，移除最多之代理人不可能停留之主機的個數 (C) 預測代理人位於某一特定主機的機率 (D) 動態轉換搜尋策略的機制 (E) 計算搜尋某一代理人所需拜訪之主機的期望個數 (F) 搜尋時配合代理人監聽的機制 (3) 設計及建構一「有服務品質保障之以代理人為基礎的服務系統」 (A) 系統架構 (B) 定義代理人服務系統中每一元件之功用及實作細節 (C) 代理人管理機制 (D) 服務品質表示方法 (E) 有服務品質保障之服務 / In this research, we study the issues of building a QoS agent-based service system in managing client mobility and agent mobility for mobile computing network. Our major contribution is classified into the following three categories: (1) Propose sets of client mobility management strategies to support clients roaming on different networks (2) Propose mobile agent search strategies to manage mobile agent mobility (3) Propose a QoS agent-based management architecture to manage clients and agents mobilities; and provide service to clients with QoS guarantee. The details are elaborated as follows: (1) Mobile client mobility management (A) Multiple GNMCs Architecture (B) Modeling client mobility behavior and network communication time (C) Criteria of choosing GNMC and LNMC for registration (D) Registration and de-registration strategies of mobile clients (E) Location tracking of mobile clients (F) Location tracking with cache policy (2) Mobile agent mobility management (A) Search strategies for mobile agents (B) Maximizing number of excluded servers in each probe (C) Estimating the residing probability that an agent resides in a server (D) Dynamic switching agent search policy (E) Evaluating the expected probing number when searches an agent (F) Agent search with listening agent (3) Design and implement a QoS agent-based service system (A) An proposed agent system architecture (B) Functionalities and implementation details of the system components (C) Agent manager design details (D) User QoS assignment and mapping to system QoS (E) Service with QoS guarantee