Spam emails are flooding the Internet. Research to prevent spam is an ongoing concern. SMTP traffic was collected from different sources in real networks and analyzed to determine the difference regarding SMTP traffic characteristics of legitimate email clients, legitimate email servers and spam relays. It is found that SMTP traffic from legitimate sites and non-legitimate sites are different and could be distinguished from each other. Some methods, which are based on analyzing SMTP traffic characteristics, were purposed to identify spam relays in the network in this thesis. An autonomous combination system, in which machine learning technologies were employed, was developed to identify spam relays in this thesis. This system identifies spam relays in real time before spam emails get to an end user by using SMTP traffic characteristics never involving email real content. A series of tests were conducted to evaluate the performance of this system. And results show that the system can identify spam relays with a high spam relay detection rate and an acceptable ratio of false positive errors.

<p>SMTP, the current protocol for sending electronic mail (e-mail) over the Internet, has for many years suffered from several problems and limitations. When it was designed, well over twenty years ago, the requirements for e-mail were very different from those of today. A message was a text message in English, and both user and machine were explicitly named in the address. The protocol was not designed to transfer other types of messages, and no mechanism was included to verify the identity of the sender.</p><p>In order to solve these shortcomings, a new e-mail protocol needs to be defined. This report specifies a basis for what such a protocol may look like. The protocol has been designed to be easy to modify and expand, as well as to benefit from more recent ideas and technology. Binary message content is transferred without conversion, sender addresses are verified, and the address format is flexible. Along with the specification of the protocol, a sample implementation has been provided.</p>

SMTP, the current protocol for sending electronic mail (e-mail) over the Internet, has for many years suffered from several problems and limitations. When it was designed, well over twenty years ago, the requirements for e-mail were very different from those of today. A message was a text message in English, and both user and machine were explicitly named in the address. The protocol was not designed to transfer other types of messages, and no mechanism was included to verify the identity of the sender. In order to solve these shortcomings, a new e-mail protocol needs to be defined. This report specifies a basis for what such a protocol may look like. The protocol has been designed to be easy to modify and expand, as well as to benefit from more recent ideas and technology. Binary message content is transferred without conversion, sender addresses are verified, and the address format is flexible. Along with the specification of the protocol, a sample implementation has been provided.

Email is one of the most used services on the Internet. It's hard to find a user with less than one own mailbox. These mailboxes are usually located on servers controlled by someone else than mailbox owners. Users trying to create their own email serverhave to install unix system and go through hard configuration process of the email server. Purpose of this work is to familiriaze reader with email history and protocols and then introduce design and implementation of an email server with easy configuration for Windows NT platform.

This thesis is about semiautomatic network protocol diagnostics and creating protocol description from eavesdropped communication. Several network eavesdropping techniques  and some common programs for network analysis are introduced. Well-known network protocols are described, with focus on their communication messages. Some already existing methods for creating models from examples are mentioned and their characteristics defined. Next we design architecture of developed tool and some methods, that create protocol description. After that we explain implementation of this tool and finally the tool is tested and experimented with.

This work deals with the implementation of support for network identifiers containing national characters in the SProbe software project, which is designed to monitor network flows. It was necessary to test and evaluate the status of selected network applications working over SMTP, POP3, IMAP, FTP or SIP protocols. On the basis of the information obtained, an extension of the current software project SProbe was proposed - a module to support network traffic monitoring with national alphabet characters. The proposed solution was then implemented and the functionality of the entire resulting system was tested. In addition, this work proposes and implements a modification of the test environment for faster and more efficient testing of the system focusing on tests containing diacritics.

The aim of Master thesis "Control and monitoring unit for optical link station" is a web server, enabling communication microcontroller with the user. The communication is based on TCP/IP model. Work an overview of the various parts of the TCP/IP model. The main part of this work is devoted to the software created. The core of unit are microcontroller C8051F120 and ethernet controller CP2200 made by Silicon Laboratories.

This master’s thesis is focused on design and realisation of special security system for space and property protection. System is devided into two parts, transmitting and receiving. Transmitting part is formed by Raspberry Pi Model B+, motion sensor, webcam and USB LTE modem Huawei E398. Receiving part consists of computer with suitable application for communication with FTP server. Data transfer in mobile systems is described in the first part of this thesis, transmitting part is designed in the second part. There is one transmitting option chosen in the third part and there are also described applications of the transmitting part. The last part of this thesis is focused on the receiving part and its application.

This project discusses optimization of e-mail and SMTP traffic in proprietary product of Microsoft Exchange 2013 in regard of marine industry. The goal is at first to analyze the requirements of this service on slow and unreliable network connections, SMTP traffic and then the product itself. Afterwards it defines specification  for the final product and prepares the test environment. Design and implementation of transport agent using Exchange Management Shell is described for synchronization of two installations of Microsoft Exchange 2013; and focuses on emerged problems during the development, discusses different approaches and possible solutions. Testing shows various shortcomings of found solution. Finally, analysis of final solution shows possible future improvements and a need of security upgrade before applying to production environment.

In diploma thesis Open Call I focus on unequal position of artists in current art world in which, despite the transparent practices like open calls, still persists the cult of name, the power of networking and personal recommendation. This topic I artistically process in form of practical artistic intervention, which is close to the tactics of 1:1 scale of Arte Útil - specifically by creation of software tool called Nomin. Its purpose is to support weakened or marginalized groups of artists. Nomin uses properties of email protocol SMTP to allow its users-spectators to send fake self-recommending emails - from email addresses of famous curators to the inboxes various galleries or other art institutions. During development of program Nomin and its technical background (software documentation, web page etc.) I followed the paradigm of free, libre, open source software (FLOSS) and also the methodology of agile software development in order to provide in this gesamtsoftwerk the users-spectators with fully functional, user-friendly software and give them possibility to influence further development of Nomin or directly participate on it. Created artwork is thus not a single artefact but rather a set of interconnected objects and practices grounded in the network of social bonds and behaviours which balances on the edge of institutional critique, useful art, participatory art and collective performance.