The exponential growth in mobile data traffic has resulted in massive energy usage and therefore has increased the carbon footprint of the Internet. Data network operators have taken significant initiatives to mitigate the negative impacts of carbon emissions (CE). Renewable Energy Sources (RES) have emerged as the most promising way to reduce carbon emissions. This article presents the role of renewable energy (RE) in minimizing the environmental impacts of mobile data communications for achieving a greener environment. In this article, an analysis of some selected mobile data network operators’ energy consumption (EC) has been presented. Based on the current statistics of different mobile network operators, the future energy values are estimated. These estimations of carbon emissions are based on the predicted data traffic in the coming years and the percentage consumption of energy from renewable sources by the network operators. The analysis presented in this article would be helpful to develop and implement energy policies that accelerate the process of increasing the renewable shares in total energy requirements. Incrementing the share of renewable energy in total energy requirements can be a way forward to reach Goal 7 of the United Nations Sustainable Development Goals (SDGs).

Variability in software-intensive systems is the ability of a software artefact (e.g., a system, subsystem, or component) to be extended, customised or configured for deployment in a specific context. Software Architecture is a high-level description of a software-intensive system that abstracts the system implementation details allowing the architect to view the system as a whole. Although variability in software architecture is recognised as a challenge in multiple domains, there has been no formal consensus on how variability should be captured or represented. The objective of this research was to provide a snapshot of the state-of-the-art on representing variability in software architecture while assessing the nature of the different approaches. To achieve this objective, a Systematic Literature Review (SLR) was conducted covering literature produced from January 1991 until June 2016. Then, grounded theory was used to conduct the analysis and draw conclusions from data, minimising threats to validity. In this paper, we report on the findings from the study.

Architecture Description Languages (ADLs) have emerged over the past two decades as a means to abstract details of large-scale systems in order to enable better intellectual control over the complete systems. Recently, there has been an explosion in the number of ADLs created in the research community. However, industrial adoption of these ADLs has been rather limited. This has been attributed to various reasons, including the lack of support of some ADLs for: variability management, requirements traceability, architectural artefact reusability and multiple architectural views. To overcome these limitations, this paper is a report on ALI, an ADL that was designed to complement existing work by adding mechanisms to address the aforementioned limitations. The ALI design principles, concepts, notations and formal semantics are presented in this paper. The notation is illustrated using two distinct case studies, one from the information systems domain " an Asset Management System (AMS); and another from the embedded systems domain - a Wheel Brake System (WBS).

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Data centers and their underline transmissions are required to guarantee critical services in a 24/7/365 framework. The extensive energy consumption of these data centers and their transmission networks impose a threat to globally available scarce energy resources. Furthermore, addressing performance and energy requirements trade-offs is also challenging. This article has been specifically focused to assess the inside-energy-view of typical data center networks and assess how network infrastructure replacements or ''refresh'' can lead to a better energy-efficient data center network (DCN) design without compromising performance or service level requirements. Server refresh techniques are found in the literature. However, considering network infrastructure refresh to attain energy efficiency is the first of its kind. A model has been proposed in this article that works on algorithms to recommend network switch replacements. The algorithms perform parametric analysis for replacement. The analysis considers parameters impacting the performance and energy consumption of the switches. In addition to technical parameters, the proposed model has also evaluated the cost impacts of the replacement. The replacement is only recommended if it is energy efficient and performance effective and validated when replacement is also cost-effective. The proposed model has been evaluated through two replacement options, one with the same manufacturer and the other with a different manufacturer. Replacement with two different options has been proposed to evaluate the impact of various manufacturers in designing a better energy-efficient data center meeting all service level requirements and performance guarantees. The results obtained from the proposed reflect the attainment of the desired objectives.