Tiek atskiro žmogaus, tiek ir šalies gyvenime saugumas – pamatinė vertybė, kuri yra neatsiejama bei labai svarbi ir šių dienų informacinių technologijų pasaulyje. Todėl, natūralu, kad informacijos saugumas tampa vis aktualesne problema. Organizacijose vykstančių procesų saugumui užtikrinti kuriami įvairūs saugumo įrankiai, kurie turi užtikrinti vartotojų ar paslaugų identiškumą (autentifikaciją), apsaugoti bendravimo vientisumą, privatumą, apibrėžti kam yra leidžiama kokius veiksmus vykdyti ir informacijos išteklius naudoti (autorizacija) ir kita. GRID sistemos suteikia galimybę naudotis WS (interneto paslaugų) pagrindu ir ne WS pagrindu paremta autentifikacija ir autorizacija GSI (GRID saugumo infrastuktūrai) užtikrinti. Abu metodai yra pagrįsti tokia pačia baze, t.y. paremti X.509 galinės esybės ir proxy sertifikatų standartu, kuris yra naudojamas identifikuojant pastovias esybes, tokias kaip vartotojai ir paslaugos, be to, leidžia priskirti laikinas privilegijas kitoms esybėms. Darbo tikslas – ištirti sertifikatų sistemą, šios sitemos komponentus, kurie yra diegiami į GRID sistemas bei pasiūlyti savo metodus ar modelius, kaip būtų galima pašalinti esamų sistemų saugumo trūkumus. Uždaviniai: 1. Išanalizuoti GRID saugumo infrastruktūros elementus ir suformuluoti egzistuojančias saugumo problemas. 2. Išanalizuoti suformuluotų problemų sprendimo būdus. 3. Remiantis problemų sprendimo būdais, suprojektuoti sertifikatų centro modelį ir proxy sertifikatų valdymo mechanizmą. 4... [toliau žr. visą tekstą] / Both in the persons and in the country's life security - the underlying value, which in these days is an integral and very important in information technology world. It is therefore natural that information security is becoming increasingly urgent problem. To ensure the safety of organizations processes the various security tools are being developed. They should ensure the identity of users or services (authentication), to protect communication integrity, privacy, to define who is allowed to carry out all activities and information resources to use (authorization) and the other. GRID system provides ability to use the WAS (Web Services) and non-WS based authentication and authorization to ensure the GSI (GRID Security infrastructure). Both methods are based on the same basis - X.509 end entity certificates and proxy certificates standard, which is used to identify end entities such as users and services, in addition, allows to assign privileges to other temporary end entities. The aim of the work – investigate a system of certificates, components of these system, which is introduced into GRID systems and to offer the methods or models how to eliminate security weaknesses in existing systems. The tasks: 1. To analyze the GRID security infrastructure elements and to formulate the existing safety problems. 2. To analyze formulated problem-solving techniques. 3. On the basis of problem-solving techniques to design certificate center model and proxy certificates management... [to full text]

Mobile agent technology presents an attractive alternative to the client-server paradigm for several network and real-time applications. However, for most applications, the lack of a viable agent security model has limited the adoption of the agent paradigm. This thesis presents a security model for mobile agents based on a security infrastructure for Computational Grids, and specifically, on X.509 Proxy Certificates. Proxy Certificates serve as credentials for Grid applications, and their primary purpose is temporary delegation of authority. Exploiting the similarity between Grid applications and mobile agent applications, this thesis motivates the use of Proxy Certificates as credentials for mobile agents. A new extension for Proxy Certificates is proposed in order to make them suited to mobile agent applications, and mechanisms are presented for agent-to-host authentication, restriction of agent privileges, and secure delegation of authority during spawning of new agents. Finally, the implementation of the proposed security mechanisms as modules within a multi-lingual and modular agent infrastructure, the Distributed Agent Delivery System, is discussed.