Šiame darbe nagrinėjami pagrindiniai internetiniai modeliai: klasikinis ir asinchroninis (AJAX) ir jų veikimo principai. Didelis dėmesys skiriamas asinchroninei sąsajai - jos veikimui, egzistuojančios programinės įrangos ir problemų apžvalgai. Tiriamajame darbe pateikiamas platus spektras realizavimo galimybių: technologijos atmainos, naudojami formatai, teigiamos ir neigiamos savybės. Taip pat pateikiamas prototipinis tokių sistemų kūrimo redaktoriaus modelis, įvertinamos rizikos realizavimo fazėje ir jų įtaka vartotojams, kūrėjams ir viso interneto saugumui. / Presented work covers main web modelis: classic and asynchronous (AJAX) and their working schemes. The author pays great attention to asynchronous interfaces – their working principles, existing software solutions and problems which may occure when developer tries to adopt them. The research work describes the range of implementation possibilities: branches of technology, usable formats, their pros and cons. Prototype model for creating asynchronous web systems and it‘s features are provided. Author introduces what problems may occur in implementation phase and what influence this technology may have on users‘, developers‘ and whole web‘s security.

With the expansion of the Internet communication and related availability of increasing number of services built on different technologies, distributed systems represent a solution to integrate these network services and provide them to users in a coherent form. The .NET Framework which provides an environment for application development in a highly distributed environment of Internet and intranet can be used to achieve this goal. This PhD thesis deals with access to shared resources in the context of distributed systems using the .NET platform. The first part of the work is devoted to describing the basic principles of distributed systems and .NET platform techniques, which can be used for implementation of the principles. For the purposes of request processing having asynchronous nature not only in distributed systems a universal interface for the description of asynchronous operations was designed and implemented. The interface extends standard asynchronous techniques on the .NET platform. In order to address the issue of access to shared resources model was designed based on the principles of object-oriented programming, along with basic algorithm to avoid deadlock in the case of use resources by multiple processes (threads) simultaneously. This extendable model has been successfully implemented and its functionality verified in basic scenarios of access to shared resources. After the definition of resources and their dependencies the implemented model allows working with resources as with any other objects on .NET platform. The synchronization processes proceed transparently in background.