{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,5]],"date-time":"2025-12-05T12:31:49Z","timestamp":1764937909051,"version":"build-2065373602"},"reference-count":58,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T00:00:00Z","timestamp":1756425600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\/MECI","award":["UID\/50008"],"award-info":[{"award-number":["UID\/50008"]}]},{"DOI":"10.13039\/501100000780","name":"EU funds","doi-asserted-by":"publisher","award":["UID\/50008"],"award-info":[{"award-number":["UID\/50008"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Instituto de Telecomunica\u00e7\u00f5es","award":["UID\/50008"],"award-info":[{"award-number":["UID\/50008"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Future Internet"],"abstract":"<jats:p>In dense urban environments and large-scale events, Internet infrastructure often becomes overloaded due to high communication demand. Many of these communications are local and short-lived, exchanged between users in close proximity but still relying on global infrastructure, leading to unnecessary network stress. In this context, delay-tolerant networks (DTNs) offer an alternative by enabling device-to-device (D2D) communication without requiring constant connectivity. However, DTNs face significant challenges in routing due to unpredictable node mobility and intermittent contacts, making reliable delivery difficult. Considering these challenges, this paper presents a hybrid Beyond 5G (B5G) DTN architecture to provide private context-aware routing in dense scenarios. In this proposal, dynamic contextual notifications are shared among relevant local nodes, combining federated learning (FL) and edge artificial intelligence (AI) to estimate the optimal relay paths based on variables such as mobility patterns and contact history. To keep the local FL models updated with the evolving context, edge nodes, integrated as part of the B5G architecture, act as coordinating entities for model aggregation and redistribution. The proposed architecture has been implemented and evaluated in simulation testbeds, studying its performance and sensibility to the node density in a realistic scenario. In high-density scenarios, the architecture outperforms state-of-the-art routing schemes, achieving an average delivery probability of 77%, with limited latency and overhead, demonstrating relevant technical viability.<\/jats:p>","DOI":"10.3390\/fi17090392","type":"journal-article","created":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T12:25:57Z","timestamp":1756470357000},"page":"392","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Hybrid B5G-DTN Architecture with Federated Learning for Contextual Communication Offloading"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0824-6956","authenticated-orcid":false,"given":"Manuel","family":"Jes\u00fas-Azabal","sequence":"first","affiliation":[{"name":"School of Information Engineering, Wenzhou Business College, Wenzhou 325015, China"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-3668-0324","authenticated-orcid":false,"given":"Meichun","family":"Zheng","sequence":"additional","affiliation":[{"name":"School of Information Engineering, Wenzhou Business College, Wenzhou 325015, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8057-5474","authenticated-orcid":false,"given":"Vasco N. G. J.","family":"Soares","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Polytechnic University of Castelo Branco, Av. Pedro \u00c1lvares Cabral, n\u00b0 12, 6000-084 Castelo Branco, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, Rua Marqu\u00eas d\u2019\u00c1vila e Bolama, 6201-001 Covilha, Portugal"},{"name":"AMA\u2014Ag\u00eancia para a Moderniza\u00e7\u00e3o Administrativa, Rua de Santa Marta, n\u00b0 55, 1150-294 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"105725","DOI":"10.1016\/j.ijmedinf.2024.105725","article-title":"Persuasive strategies in digital interventions to combat internet addiction: A systematic review","volume":"195","author":"Theopilus","year":"2025","journal-title":"Int. J. Med. Inform."},{"key":"ref_2","unstructured":"Barolli, L. (2025). 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