{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,28]],"date-time":"2025-10-28T00:29:16Z","timestamp":1761611356410,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2014,6,4]],"date-time":"2014-06-04T00:00:00Z","timestamp":1401840000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"funder":[{"name":"European Union\u2019s Seventh Framework Programme (FP7\/2007-2013)","award":["258885"],"award-info":[{"award-number":["258885"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Smart embedded objects will become an important part of what is called the Internet of Things. Applications often require concurrent interactions with several of these objects and their resources. Existing solutions have several limitations in terms of reliability, flexibility and manageability of such groups of objects. To overcome these limitations we propose an intermediately level of intelligence to easily manipulate a group of resources across multiple smart objects, building upon the Constrained Application Protocol (CoAP). We describe the design of our solution to create and manipulate a group of CoAP resources using a single client request. Furthermore we introduce the concept of profiles for the created groups. The use of profiles allows the client to specify in more detail how the group should behave. We have implemented our solution and demonstrate that it covers the complete group life-cycle, i.e., creation, validation, flexible usage and deletion. Finally, we quantitatively analyze the performance of our solution and compare it against multicast-based CoAP group communication. The results show that our solution improves reliability and flexibility with a trade-off in increased communication overhead.<\/jats:p>","DOI":"10.3390\/s140609833","type":"journal-article","created":{"date-parts":[[2014,6,4]],"date-time":"2014-06-04T10:28:36Z","timestamp":1401877716000},"page":"9833-9877","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Flexible Unicast-Based Group Communication for  CoAP-Enabled Devices"],"prefix":"10.3390","volume":"14","author":[{"given":"Isam","family":"Ishaq","sequence":"first","affiliation":[{"name":"Department of Information Technology (INTEC), Ghent University - iMinds, Gaston  Crommenlaan 8 Bus 201, Ghent 9050, Belgium"},{"name":"Said Khoury IT Center of Excellence (SKITCE), Al-Quds University, Abu Deis,  Jerusalem 51000, Palestine"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2039-007X","authenticated-orcid":false,"given":"Jeroen","family":"Hoebeke","sequence":"additional","affiliation":[{"name":"Department of Information Technology (INTEC), Ghent University - iMinds, Gaston  Crommenlaan 8 Bus 201, Ghent 9050, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Floris","family":"Van den Abeele","sequence":"additional","affiliation":[{"name":"Department of Information Technology (INTEC), Ghent University - iMinds, Gaston  Crommenlaan 8 Bus 201, Ghent 9050, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jen","family":"Rossey","sequence":"additional","affiliation":[{"name":"Department of Information Technology (INTEC), Ghent University - iMinds, Gaston  Crommenlaan 8 Bus 201, Ghent 9050, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2377-3674","authenticated-orcid":false,"given":"Ingrid","family":"Moerman","sequence":"additional","affiliation":[{"name":"Department of Information Technology (INTEC), Ghent University - iMinds, Gaston  Crommenlaan 8 Bus 201, Ghent 9050, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Piet","family":"Demeester","sequence":"additional","affiliation":[{"name":"Department of Information Technology (INTEC), Ghent University - iMinds, Gaston  Crommenlaan 8 Bus 201, Ghent 9050, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ishaq, I., Hoebeke, J., Van den Abeele, F., Moerman, I., and Demeester, P. (2013, January 20\u201323). Group Communication in Constrained Environments Using CoAP-based Entities. Cambridge, MA, USA.","DOI":"10.1109\/DCOSS.2013.14"},{"key":"ref_2","unstructured":"Kushalnagar, N., Montenegro, G., and Schumacher, C.P.P. IPv6 over Low-Power Wireless Personal Area Networks (6LoWPANs): Overview, Assumptions, Problem Statement, and Goals RFC 4919. Available online: http:\/\/datatracker.ietf.org\/doc\/rfc4919\/."},{"key":"ref_3","unstructured":"Constrained RESTful Environments (core). Available online: http:\/\/datatracker.ietf.org\/wg\/core\/."},{"key":"ref_4","unstructured":"Constrained RESTful Environments (core)\u2014Charter for Working Group. Available online: https:\/\/datatracker.ietf.org\/wg\/core\/charter\/."},{"key":"ref_5","unstructured":"Shelby, Z., Hartke, K., and Bormann, C. Constrained Application Protocol (CoAP) draft-ietf-core-coap-18. Avaiable online: http:\/\/tools.ietf.org\/html\/draft-ietf-core-coap-18."},{"key":"ref_6","unstructured":"Colitti, W., Steenhaut, K., and de Caro, N. (2011, January 11). Integrating Wireless Sensor Networks with the Web. Chicago, IL, USA."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Yazar, D., and Dunkels, A. (2009, January 4\u20136). Efficient application integration in IP-based sensor networks. Berkeley, CA, USA.","DOI":"10.1145\/1810279.1810289"},{"key":"ref_8","unstructured":"Modadugu, N., and Rescorla, E. Datagram Transport Layer Security. Avaiable online: http:\/\/tools.ietf.org\/html\/rfc4347."},{"key":"ref_9","first-page":"76","article-title":"Embedded web services","volume":"291","author":"Shelby","year":"2010","journal-title":"IEEE Wirel. Commun."},{"key":"ref_10","unstructured":"Nottingham, M. Web Linking RFC 5988. Avaiable online: http:\/\/datatracker.ietf.org\/doc\/rfc5988\/."},{"key":"ref_11","unstructured":"Shelby, Z. Constrained RESTful Environments (CoRE) Link Format RFC 6690. Avaiable online: http:\/\/datatracker.ietf.org\/doc\/rfc6690\/."},{"key":"ref_12","unstructured":"Shelby, Z., Krco, S., and Bormann, C. CoRE Resource Directory draft-shelby-core-resource-directory-04. Avaiable online: http:\/\/tools.ietf.org\/html\/draft-shelby-core-resource-directory-04."},{"key":"ref_13","unstructured":"Bormann, C., and Shelby, Z. Blockwise Transfers in CoAP draft-ietf-core-block-14. Avaiable online: http:\/\/tools.ietf.org\/html\/draft-ietf-core-block-14."},{"key":"ref_14","unstructured":"Rahman, A., and Dijk, E. Group Communication for CoAP draft-ietf-core-groupcomm-18. Avaiable online: http:\/\/tools.ietf.org\/html\/draft-ietf-core-groupcomm-18."},{"key":"ref_15","unstructured":"Shelby, Z., and Chauvenet, C. The IPSO Application Framework draft-ipso-app-framework-04. Avaiable online: http:\/\/www.ipso-alliance.org\/wp-content\/media\/draft-ipso-app-framework-04.pdf."},{"key":"ref_16","unstructured":"Keranen, A., Ersue, M., and Bormann, C. Terminology for Constrained Node Networks draft-ietf-lwig-terminology-07. Avaiable online: http:\/\/tools.ietf.org\/html\/draft-ietf-lwig-terminology-07."},{"key":"ref_17","unstructured":"Lai, S. (2009). Heterogenous Quorum-Based Wakeup Scheduling for Duty-Cycled Wireless Sensor Networks. [Ph.D. Thesis, Virginia Polytechnic Institute and State University]."},{"key":"ref_18","unstructured":"Hui, J., and Kelsey, R. Multicast Protocol for Low Power and Lossy Networks (MPL) draft-ietf-roll-trickle-mcast-04. Avaiable online: http:\/\/tools.ietf.org\/html\/draft-ietf-roll-trickle-mcast-03."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1089","DOI":"10.1007\/s11277-013-1250-5","article-title":"IPv6 Multicast Forwarding in RPL-Based Wireless Sensor Networks","volume":"73","author":"Oikonomou","year":"2013","journal-title":"Wirel. Pers. Commun."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Jung, M., and Kastner, W. (2013, January 10\u201313). Efficient group communication based on Web services for reliable control in wireless automation. Vienna, Australia.","DOI":"10.1109\/IECON.2013.6700071"},{"key":"ref_21","unstructured":"Shelby, Z., and Vial, M. CoRE Interfaces draft-shelby-core-interfaces-03. Avaiable online: http:\/\/tools.ietf.org\/html\/draft-shelby-core-interfaces-03."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Hasemann, H., Kleine, O., Kroeller, A., and Leggieri, M. (2013, January 13\u201315). Annotating Real-World Objects Using Semantic Entities. Ghent, Belgium.","DOI":"10.1007\/978-3-642-36672-7_5"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1007\/s11390-014-1423-z","article-title":"SeaHttp: A Resource-Oriented Protocol to Extend REST Style for Web of Things","volume":"29","author":"Hou","year":"2014","journal-title":"J. Comput. Sci. Technol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1145\/2140522.2140530","article-title":"Utility-based bandwidth adaptation in mission-oriented wireless sensor networks","volume":"8","author":"Eswaran","year":"2012","journal-title":"ACM Trans. Sens. Netw."},{"key":"ref_25","unstructured":"Greevenbosch, B., Hoebeke, J., and Ishaq, I. CoAP Profile Description Format draft-greevenbosch-core-profile-description-01. Avaiable online: http:\/\/tools.ietf.org\/html\/draft-greevenbosch-core-profile-description-01."},{"key":"ref_26","unstructured":"Introducing JSON Available online: http:\/\/www.json.org\/."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Ishaq, I., Hoebeke, J., Rossey, J., de Poorter, E., Moerman, I., and Demeester, P. (2012, January 4\u20136). Facilitating Sensor Deployment, Discovery and Resource Access Using Embedded Web Services. Palermo, Italy.","DOI":"10.1109\/IMIS.2012.48"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1145\/354871.354874","article-title":"The click modular router","volume":"18","author":"Kohler","year":"2000","journal-title":"ACM Trans. Comput. Syst."},{"key":"ref_29","unstructured":"Zolertia Z1 Platform Available online: http:\/\/www.zolertia.com\/ti."},{"key":"ref_30","unstructured":"Contiki: The Open Source Operating System for the Internet of Things. Available online: http:\/\/www.contiki-os.org\/."},{"key":"ref_31","unstructured":"Erbium (Er) REST Engine and CoAP Implementation for Contiki. Available online: http:\/\/people.inf.ethz.ch\/mkovatsc\/erbium.php."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Oikonomou, G., and Phillips, I. (2012, January 19\u201323). Stateless multicast forwarding with RPL in 6LowPAN sensor networks. Lugano, Switzerland.","DOI":"10.1109\/PerComW.2012.6197494"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Lerche, C., Hartke, K., and Kovatsch, M. (2012, January 17\u201321). Industry Adoption of the Internet of Things: A Constrained Application Protocol Survey. Krak\u00f3w, Poland.","DOI":"10.1109\/ETFA.2012.6489787"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Den Abeele, F., Hoebeke, J., Ishaq, I., Teklemariam, G.K., Rossey, J., Moerman, I., and Demeester, P. (2013, January 11\u201315). Building embedded applications via REST services for the Internet of Things. Roma, Italy.","DOI":"10.1145\/2517351.2517426"},{"key":"ref_35","unstructured":"Bouckaert, S., Vandenberghe, W., Jooris, B., Moerman, I., and Demeester, P. (2010, January 18\u201320). The w-iLab.t testbed. Berlin, Germany."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/6\/9833\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:12:07Z","timestamp":1760217127000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/6\/9833"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,6,4]]},"references-count":35,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2014,6]]}},"alternative-id":["s140609833"],"URL":"https:\/\/doi.org\/10.3390\/s140609833","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2014,6,4]]}}}