Rethinking Sustainable Campus Networking: Evidence from MST-Based Cabling Optimization and Device-Level Energy Consumption Measurements

Abstract

The digitalization of university campuses has intensified the need for reliable, energy-efficient, and sustainable network infrastructures. While Wi-Fi systems offer flexibility and ease of deployment, their long-term energy footprint often exceeds that of wired alternatives. Conversely, Ethernet networks, though more stable and efficient, require careful optimization to reduce installation costs and material use. This study develops a two-stage framework that combines graph-theoretic optimization with empirical device-level measurements to inform sustainable campus network design. In the first phase, the physical network layout was modeled as a Minimum Spanning Tree (MST) using the Manhattan distance metric to reflect realistic in-building cable routing. The MST was solved via Kruskal’s algorithm and validated through a mixed-integer programming model implemented in Gurobi, yielding a total cable length of 1,435.69 metres and a 63.4% reduction in total cable length—implying comparable savings in material and installation costs—compared with a naive layout. In the second phase, an experimental analysis examined the energy consumption of Wi-Fi, native Ethernet, and Ethernet-adapter connections across multiple devices. Although the paired t-tests revealed no statistically significant differences at the 95% confidence level, the results indicate that device-specific characteristics play a crucial role in determining actual energy efficiency. Overall, the findings underscore the importance of integrating optimization and empirical evaluation in sustainable network planning. The proposed framework not only supports cost-efficient infrastructure decisions but also contributes to the broader goal of reducing the carbon footprint of digital campuses.

Keywords

• : Minimum spanning tree
• layout planning
• mixed integer programming
• Kruskal algorithm
• t-statistic

Supporting Institution

Scientific and Technological Research Council of Türkiye (TÜBİTAK), 2209-A Research Projects Support Programme for Undergraduate Students, Project No: 1919B012319079.

Project Number

1919B012319079

Ethical Statement

This research does not involve experiments on human or animal subjects and does not collect any personal or sensitive data. The study is based on technical measurements on electronic devices and simulated network layouts. Therefore, in accordance with national and institutional guidelines, formal ethics committee approval was not required.

Thanks

This article is based on the results of an undergraduate research project supported by the Scientific and Technological Research Council of Türkiye (TÜBİTAK) under the 2209-A Research Projects Support Programme for Undergraduate Students (Project No: 1919B012319079). The authors sincerely thank TÜBİTAK for its financial support and encouragement throughout the research process. The authors are solely responsible for all evaluations and interpretations presented in this study.

Kampüs Ağlarını Sürdürülebilirlik Perspektifinden Yeniden Düşünmek: MST Tabanlı Kablolama Optimizasyonu ve Cihaz Düzeyinde Enerji Tüketimleri

Abstract

Bu çalışma, üniversite kampüslerinde dijital ağ altyapısının sürdürülebilirlik odağında nasıl tasarlanabileceğine ilişkin bütüncül bir yaklaşım önermektedir. Önerilen çerçeve, bir yandan kablolu ağın fiziksel tasarımını iyileştirirken, diğer yandan uç cihazların farklı bağlantı türleri altındaki enerji tüketimini deneysel olarak inceleyen iki aşamalı bir yapıya dayanmaktadır. İlk aşamada, bir üniversite binasının tek katına ait yerleşim planı kullanılarak düğümler arası mesafeler iç mekân koşullarını daha gerçekçi yansıtan Manhattan uzaklığı ile hesaplanmış ve Minimum Yayılan Ağaç (MST) modeli aracılığıyla toplam Ethernet kablo uzunluğu minimize edilmiştir. Kruskal algoritması ve karma tamsayılı doğrusal programlama ile çözülen model, naif yerleşim senaryosuna kıyasla kablo metrajında %63,4’lük bir azalma (3.927 metreden 1.435,69 metreye) sağlamaktadır. İkinci aşamada ise dizüstü bilgisayar ve akıllı telefondan oluşan bir cihaz seti için Wi-Fi, yerleşik Ethernet ve adaptörlü Ethernet bağlantıları altında, 4K video akışı, büyük dosya indirme, bulut yedekleme ve çevrim içi toplantı gibi yüksek yük koşullarında enerji tüketimi ölçülmüş; elde edilen veriler eşleştirilmiş örneklem t-testleri ile analiz edilmiştir. Bulgular, bağlantı türleri arasındaki tüketim farklarının küçük kaldığını ve istatistiksel olarak anlamlı düzeye ulaşmadığını göstermektedir. Genel olarak sonuçlar, kampüs ağlarında sürdürülebilirlik açısından en büyük ve öngörülebilir kazanımların altyapı düzeyindeki kablolama ve donanım kararlarından kaynaklandığını, uç cihazların bağlantı tercihlerinin ise daha sınırlı bir etkiye sahip olduğunu ortaya koymaktadır.

Keywords

• Minimum yayılan ağaç
• yerleşim planlama
• karma tam sayılı programlama
• Kruskal algoritması
• t-istatistiği

Supporting Institution

Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK), 2209-A Üniversite Öğrencileri Araştırma Projeleri Destekleme Programı, Proje No: 1919B012319079.

Project Number

1919B012319079

Ethical Statement

Bu araştırma insan veya hayvan denekler üzerinde deney içermemekte ve kişisel ya da hassas veri toplamamaktadır. Çalışma, elektronik cihazlar üzerinde yapılan teknik ölçümler ve simüle edilmiş ağ yerleşimleri temelinde yürütülmüştür. Bu nedenle ulusal ve kurumsal mevzuat çerçevesinde etik kurul onayı gerektirmemektedir. Araştırmanın tüm süreçlerinde ve raporlanmasında bilimsel araştırma ve yayın etiği ilkelerine uyulduğunu yazarlar beyan eder.

Thanks

Bu makale, Türkiye Bilimsel ve Teknolojik Araştırma Kurumu’nun (TÜBİTAK) 2209-A Üniversite Öğrencileri Araştırma Projeleri Destekleme Programı çerçevesinde desteklenen 1919B012319079 numaralı lisans araştırma projesinden türetilmiştir. Araştırma sürecine sağladığı mali katkı ve teşvik için TÜBİTAK’a içtenlikle teşekkür ederiz. Çalışmada yer alan değerlendirme ve yorumların tüm sorumluluğu yazarlara aittir.

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