A Practical Study of E-mail Communication through SMTP

Simple Mail Transfer Protocol (SMTP) is an application layer protocol for e-mail communication. It has been adopted as a standard by Internet Engineering Task Force (IETF). SMTP has set conversational and grammatical rules for exchanging messages between connected computers. It has evolved through several revisions and extensions since its formation by Jon Postel in 1981. In SMTP, the sender establishes a full-duplex transmission channel with a receiver. The receiver may be either the ultimate destination or an intermediate forwarding agent. SMTP commands are issued by the sender and are sent to the receiver, which responds to these commands through codes. Each SMTP session between the sender and the receiver consists of three phases namely: connection establishment, mail transactions and connection termination. This paper describes and illustrates the process of e-mail communication through SMTP by issuing the individual SMTP commands directly to transmit e-mail messages. It also describes individual SMTP commands and extensions with practical implementation using a Telnet client

Capture and analysis of the NFS workload of an ISP email service

Tese de mestrado Segurança Informática, Universidade de Lisboa, Faculdade de Ciências, 2009Os objectivos desta tese são capturar a carga de comandos NFS de um serviço de email de um provedor de Internet, converter a captura para um formato mais flexível, e analisar as características do mesmo. Até ao momento, nenhum outro trabalho publicado, analisou a carga de comandos de um serviço de email de um provedor de Internet. Um novo estudo, irá ajudar a compreender qual o impacto das diferenças na carga de comandos de um sistema de ficheiros de rede, e o que caracteriza a carga de comandos de um sistema de email real. A captura será analisada, de forma a encontrar novas propriedades que futuros sistemas de ficheiros poderão suportar ou explorar. Nesta tese, fazemos uma análise exaustiva de como capturar altos débitos de tráfego, que envolve vários desafios. Identificamos os problemas encontrados e explicamos como contornar esses problemas. Devido ao elevado tamanho da captura e devido ao espaço limitado de armazenamento disponível, precisámos de converter a captura para um formato mais compacto e flexível, de forma a podermos fazer uma análise de forma eficiente. Descrevemos os desafios para analisar grandes volumes de dados e quais as técnicas utilizadas. Visto que a captura contém dados sensíveis das caixas de correio dos utilizadores, tivemos que anonimizar a captura. Descrevemos que dados têm de ser anonimizados de forma a disponibilizarmos a captura gratuitamente. Também analisamos a captura e demonstramos as características únicas da captura estudada, tais como a natureza periódica da actividade do sistema de ficheiros, a distribuição de tamanhos de todos os ficheiros acedidos, a sequencialidade dos dados acedidos e os tipos de anexos mais comuns numa típica caixa de correio.The aims of this thesis are to capture a real-world NFS workload of an ISP email service, convert the traces to a more useful and flexible format and analyze the characteristics of the workload. No published work has ever analyzed a large-scale, real-world ISP email workload. A new study will help to understand how these changes impact network file system workloads and what characterizes a real-world email workload. Storage traces are analyzed to find properties that future systems should support or exploit. In this thesis, we provide an in-depth explanation of how we were able to capture high data rates, which involves several challenges. We identify the bottlenecks faced and explain how we circumvented them. Due to the large size of the captured workload and limited available storage, we needed to convert the traces to a more compact and flexible format so we could further analyze the workload in an efficient manner. We describe the challenges of analyzing large datasets and the techniques that were used. Since the workload contains sensitive information about the mailboxes, we had to anonymize the workload. We will describe what needed to be anonymized and how it was done. This was an important step to get permission from the ISP to publish the anonymized traces, which will be available for free download. We also performed several analyses that demonstrate unique characteristics of the studied workload, such as the periodic nature of file system activity, the file size distribution for all accessed files, the sequentiality of accessed data, and the most common type of attachments found in a typical mailbox

ebXML: Global Standard for Electronic Business

Business-to-business integration is transforming the market and has already begun to increase the efficiency of those companies involved. EDI (Electronic Document Interchange) became very popular during 1970’s; Today EDI transactions total about $750 billion year. EDI is being used by 90% of Fortune 1000 companies. It has indeed become a dominant technology for the largest companies, on the other hand it has been adopted by less than 5% of small and medium sized companies in general and, of these, many use EDI only because their larger customers require it. The reason behind is that EDI is a difficult, complex technology to implement usually comes with high transactional cost. Hence it is suitable for large companies with large volume of transactions. EDI uses fixed, rigid and compressed data format that is difficult to decipher and debug. The data exchange in EDI happens in proprietary VAN (value added network) which is an expensive solution. EbXML (Electronic Business XML) envisioned creating a single global electronic marketplace where enterprises of any size and in any geographic location can meet and conduct business with each other through exchange of xml based messages. The XML (the Extensible Markup Language) has rapidly imposed itself as a popular format for exchange of information on the web. The very nature of XML is that it is a structured document format, in that it represents not only the information to be exchanged, but the metadata encapsulating its meaning. XML technology has potential to solve the existing problems in current EDI systems. Using ebXML, companies have a standard method to exchange business messages, conduct trading relationships, communicate data in common terms and define and register business processes. EbXML is designed to provide a simple way for companies to find one another and conduct business over the Web, allowing those with different platforms to speak a common language. EbXML targets to provide low cost solutions for small and medium enterprises as well as complex solution for large enterprises. This project attempts to implement a prototype of ebXML messaging service as per ebXML specification to obtain the insight look of feasibility and suitability of XML solution for EDI

Unifying Internet Services Using Distributed Shared Objects

Developing wide area applications such as those for sharing data across the Internet is unnecessarily difficult. The main problem is the widespread use of a communication paradigm that is too low level. We will show how wide area application development can be made easier when using distributed shared objects instead of a communication-oriented model. An object in our model is physically distributed, with multiple copies of its state on different machines. All implementation aspects such as replication, distribution, and migration of state, are hidden from users through an object's interface. In this paper, we concentrate on the application of distributed shared objects, by providing an outline of a middleware solution that permits integration of the Internet services for e-mail, News, file transfer, and Web documents. vrije Universiteit Faculty of Mathematics and Computer Science 1 Introduction Constructing wide area applications, such as those for sharing data across the Internet,..

Unified Internet Messaging

As telephony services, mobile services and internet services continue to converge, the prospect of providing Unified Messaging and even Unified Communications becomes increasingly achievable. This paper discusses the growing importance of IP-based networks to Unified Messaging developments and examines some of the key services and protocols that are likely to make Unified Messaging more widely available. In this initial paper, we limit ourselves initially to the unification of text-based messaging using SMS and Email. The approach we make is based on the existing Internet Email framework but will take cognisance of the need to add voice and other non-text based messaging and communications at a later stage. Ultimately, the research project aims to build a working prototype of a generic messaging model that works for both non realtime and real-time communications. This model will provide a framework into which existing and future messaging protocols can be plugged. This paper originated from an applied research project which examined the integration possibilities for various messaging and communications protocol

Automated order processing and responses

Dissertação de mestrado integrado em Engenharia InformáticaThis dissertation was carried out at Utilmédica - Produtos Medicos Hospitalares, Lda which was born on June 9, 2004, as a result of the perception of gaps in the market for the supply of medical - hospital products and equipment to health professionals. One of their main goals is to provide healthcare professionals with the best solutions for the noble mission of ensuring the welfare of us all. Due to this vision and consequent growth, the company’s working methods also need to grow. Therefore, the company wanted to find a solution to the growing quotation requests by the various messaging platforms in which they are present. Starting from this problem, a system was developed that identifies the products contained in a given message and sends an automatic quotation reply. This system was named Rissa and to develop it, it was necessary to analyse the content of previous email messages, in order to develop a NLP model that could identify the entities present in future email messages. In addition to this, Rissa also contains a search system that filters only the products available from the company. Rissa had to integrate into an existing infrastructure without impacting the company’s op eration. This integration had to deal not only with external services, but also with internal services and privacy policies. In the end, this system was implemented in the company in a real work situation to obtain production results.Esta dissertação realizou-se na empresa Utilmédica - Produtos Medicos Hospitalares, Lda que nasceu a 9 de Junho de 2004, como resultado da perceção de lacunas no mercado para o fornecimento de produtos e equipamentos médicos - hospitalares aos profissionais de saúde. Um dos seus principais objetivos é fornecer aos profissionais de saúde as melhores soluções para a nobre missão de garantir o bem-estar de todos nós. Devido a esta visão e consequentemente ao crescimento, os métodos de trabalho da empresa também precisam de crescer. Por isso a empresa gostava de encontrar uma solução para o crescente pedido de orçamentos pelas várias plataformas de mensagens. Partindo deste problema, foi desenvolvido um sistema que identifica os produtos contidos numa determinada mensagem e envia uma resposta automática de orçamento. Este sistema foi apelidado de Rissa e para o desenvolver foi necessário analisar o conteúdo das mensagens de email anteriores de modo a desenvolver um modelo de NLP que fosse capaz de identificar as entidades nas mensagens de email futuras. Para além disto, Rissa contém um sistema de pesquisa de modo a filtrar apenas os produtos disponibilizados pela empresa. Rissa teve de se integrar numa infraestrutura já existente sem afetar o funcionamento da empresa. Esta integração teve de lidar não só com os serviços externos, mas também com serviços e políticas de privacidade internas. No final, este sistema foi implementado na empresa numa situação de trabalho real para se obter resultados de produção

Preserving Validity of MS Exchange Headers on Filtering SMTP Proxy-Server

Cílem této práce je lokalizace a návrh optimálního řešení problému, způsobujícího vzájemnou nekompatibilitu SMTP proxy-serveru AVG Linux Server Edition a poštovního serveru Microsoft Exchange. Práce popisuje různé možnosti řešení tohoto problému a určuje tu nejvhodnější z nich. V teoretické části poskytuje tato práce základní přehled o protokolu SMTP a o protokolech serveru Microsoft Exchange. Dále popisuje nejčastější hrozby týkajíci se e-mailové komunikace uživatelů a různé způsoby ochrany před nimi.The aim of this thesis is the localization and finding an optimal solution for a compatibility issue between two products, the AVG Linux Server Edition SMTP proxy-server and the Microsoft Exchange e-mail server. There are several possible solutions of this issue described and the most effective one is suggested as the final solution. In the first part, this thesis is providing a basic overview of the SMTP protocol and the protocols used in the Microsoft Exchanage server. The most common threats in the e-mail communication are also discussed here and several available solutions of protection against them are presented.