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

Study of Botnets and Their Threats to Internet Security

Among all media of communications, Internet is most vulnerable to attacks owing to its public nature and virtually without centralized control. With the growing financial dealings and dependence of businesses on Internet, these attacks have even more increased. Whereas previously hackers would satisfy themselves by breaking into someone’s system, in today\u27s world hackers\u27 work under an organized crime plan to obtain illicit financial gains. Various attacks than include spamming, phishing, click fraud, distributed denial of services, hosting illegal material, key logging, etc. are being carried out by hackers using botnets. In this paper a detailed study of botnets vis-a-vis their creation, propagation, command and control techniques, communication protocols and relay mechanism is presented. The aim of this paper is to gain an insight of security threats that users of Internet are facing from hackers by the use of malicious botnets

Digital Library - An Inevitable Resource for Modern Day Research in Developing Countries

Research in any area requires an extensive collection and study of relevant literature. The research literature may be found in different libraries dispersed at different geographical locations. The conventional library systems pose some potential difficulties in acquiring timely information and therefore impede the research activity. This paper presents use of digital libraries in carrying out cost-effective and quality research. With technology innovations, a commensurate progress is required in the development and maintenance of the knowledge base. Statistics have shown that the research activity has increased with the digitization of the information and its easy availability to the researchers especially in developing countries. The digital library has thus become an inevitable source of information for researchers around the globe especially in developing countries to maintain the pace of research in a highly competitive world

Working Papers on Information Systems Study of Botnets and Their Threats to Internet Security

Abstract Among all media of communications, Internet is most vulnerable to attacks owing to its public nature and virtually without centralized control. With the growing financial dealings and dependence of businesses on Internet, these attacks have even more increased. Whereas previously hackers would satisfy themselves by breaking into someoneâ s system, in today's world hackers' work under an organized crime plan to obtain illicit financial gains. Various attacks than include spamming, phishing, click fraud, distributed denial of services, hosting illegal material, key logging, etc. are being carried out by hackers using botnets. In this paper a detailed study of botnets vis-a-vis their creation, propagation, command and control techniques, communication protocols and relay mechanism is presented. The aim of this paper is to gain an insight of security threats that users of Internet are facing from hackers by the use of malicious botnets

Simulation and Modelling of Hydrogen Production from Waste Plastics: Technoeconomic Analysis

The global energy demand is expected to increase by 30% within the next two decades. Plastic thermochemical recycling is a potential alternative to meet this tremendous demand because of its availability and high heating value. Polypropylene (PP) and polyethylene (PE) are considered in this study because of their substantial worldwide availability in the category of plastic wastes. Two cases were modeled to produce hydrogen from the waste plastics using Aspen Plus®. Case 1 is the base design containing three main processes (plastic gasification, syngas conversion, and acid gas removal), where the results were validated with the literature. On the other hand, case 2 integrates the plastic gasification with steam methane reforming (SMR) to enhance the overall hydrogen production. The two cases were then analyzed in terms of syngas heating values, hydrogen production rates, energy efficiency, greenhouse gas emissions, and process economics. The results reveal that case 2 produces 5.6% more hydrogen than case 1. The overall process efficiency was enhanced by 4.13%. Case 2 reduces the CO2 specific emissions by 4.0% and lowers the hydrogen production cost by 29%. This substantial reduction in the H2 production cost confirms the dominance of the integrated model over the standalone plastic gasification model

Technoeconomic Feasibility of Hydrogen Production from Waste Tires with the Control of CO2Emissions

The worldwide demand for energy is increasing significantly, and the landfill disposal of waste tires and their stockpiles contributes to huge environmental impacts. Thermochemical recycling of waste tires to produce energy and fuels is an attractive option for reducing waste with the added benefit of meeting energy needs. Hydrogen is a clean fuel that could be produced via the gasification of waste tires followed by syngas processing. In this study, two process models were developed to evaluate the hydrogen production potential from waste tires. Case 1 involves three main processes: The steam gasification of waste tires, water gas shift, and acid gas removal to produce hydrogen. On the other hand, case 2 represents the integration of the waste tire gasification system with the natural gas reforming unit, where the energy from the gasifier-derived syngas can provide sufficient heat to the steam methane reforming (SMR) unit. Both models were also analyzed in terms of syngas compositions, H2production rate, H2purity, overall process efficiency, CO2emissions, and H2production cost. The results revealed that case 2 produced syngas with a 55% higher heating value, 28% higher H2production, 7% higher H2purity, and 26% lower CO2emissions as compared to case 1. The results showed that case 2 offers 10.4% higher process efficiency and 28.5% lower H2production costs as compared to case 1. Additionally, the second case has 26% lower CO2-specific emissions than the first, which significantly enhances the process performance in terms of environmental aspects. Overall, the case 2 design has been found to be more efficient and cost-effective compared to the base case design

Technoeconomic Feasibility of Hydrogen Production from Waste Tires with the Control of CO2Emissions

The worldwide demand for energy is increasing significantly, and the landfill disposal of waste tires and their stockpiles contributes to huge environmental impacts. Thermochemical recycling of waste tires to produce energy and fuels is an attractive option for reducing waste with the added benefit of meeting energy needs. Hydrogen is a clean fuel that could be produced via the gasification of waste tires followed by syngas processing. In this study, two process models were developed to evaluate the hydrogen production potential from waste tires. Case 1 involves three main processes: The steam gasification of waste tires, water gas shift, and acid gas removal to produce hydrogen. On the other hand, case 2 represents the integration of the waste tire gasification system with the natural gas reforming unit, where the energy from the gasifier-derived syngas can provide sufficient heat to the steam methane reforming (SMR) unit. Both models were also analyzed in terms of syngas compositions, H2production rate, H2purity, overall process efficiency, CO2emissions, and H2production cost. The results revealed that case 2 produced syngas with a 55% higher heating value, 28% higher H2production, 7% higher H2purity, and 26% lower CO2emissions as compared to case 1. The results showed that case 2 offers 10.4% higher process efficiency and 28.5% lower H2production costs as compared to case 1. Additionally, the second case has 26% lower CO2-specific emissions than the first, which significantly enhances the process performance in terms of environmental aspects. Overall, the case 2 design has been found to be more efficient and cost-effective compared to the base case design