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Opportunistic networking

Complex Dynamic Networks are characterised by a stochastic nature where the behaviour of nodes is random and unknown. From a routing viewpoint, data exchange is rather challenging in such networks since paths between any pair of nodes may never exist or delay may be too long to be accepted by current data transport protocols. Intermittent connect networks can be found in a village scenarios, corresponding to sparse networks, as well as cities, where the existence of a high number of wireless access points does not guarantee pervasive connectivity due to the high radio interference levels, the high percentage of close access points and the high cost of cellular data services.

Opportunistic routing has proven to be able to cope with the stochastic behaviour present in networks that display topologies with patterns of connections that are neither purely regular nor random. With opportunistic routing, forwarding decisions are made using locally collected knowledge about node behaviour to predict which nodes are likely to deliver a content or bring it closer to the destination.

Most solutions consider human mobility as the key aspect for opportunistic routing. However, human mobility is quite difficult to predict and routing table updates must occur whenever mobility occurs. This is quite unfeasible especially in scenarios where nodes are highly dynamic and links represent intermittent connectivity, resulting in a high consumption of network resources and frequent routing table updates.

The goal of our research activity is to investigate solutions able to ensure efficient opportunistic routing in scenarios with intermittent Internet connectivity, based on the social interaction of users carrying portable wireless devices. Social relationships can be rather useful given the fact that topology based on them changes less frequently than the ones based on mobility.

Book Chapters

Namusale Chama, Antonio Junior, Waldir Moreira, Paulo Mendes, Rute Sofia, “User-centric Networking, Routing Aspects”, Springer Lecture Notes in Social Networks, User-Centric Networking: Future Perspectives, ISBN 978-3-319-05217-5, May 2014

Waldir Moreira, Paulo Mendes, "Social-aware Opportunistic Routing: The new trend", Springer Book on Routing in Opportunistic Networks, ISBN 978-1-4614-3513-6, August 2013

Journal Publications

Waldir Moreira, Paulo Mendes, "Impact of Human Behavior on Social Opportunistic Forwarding", Elsevier Ad Hoc Networks, Special Issue on New Research Challenges in Mobile, Opportunistic and Delay-Tolerant Networks, July 2014

Ronedo Ferreira, Waldir Moreira, Paulo Mendes, Mario Gerla, Eduardo Cerqueira, "Improving the Delivery Rate of Digital Inclusion Applications for Amazon Riverside Communities by Using an Integrated Bluetooth DTN Architecture", International Journal of Computer Science and Network Security, Vol.14, no.1, January 2014

Waldir Moreira, Paulo Mendes, Susana Sargento, "Assessment Model for Opportunistic Routing", IEEE Latin America Transactions, Vol 10 Issue 3 April 2012

Conference Publications

Waldir Moreira, Paulo Mendes, “Dynamics of Social-aware Pervasive Networks” in Proc. of IEEE PERCOM workshop (PerMoby), St. Louis, USA, March 2015

Waldir Moreira, Paulo Mendes, Susana Sargento, "Social-aware Opportunistic Routing Protocol based on User's Interactions and Interests", in Proc. of AdhocNets, Barcelona, Spain, October 2013

Waldir Moreira, Ronedo Ferreira, Douglas Cirqueira, Paulo Mendes and Eduardo Cerqueira "SocialDTN: A DTN implementation for Digital and Social Inclusion", in Proc. of ACM Mobicom workshop on Lowest cost denominator networking for universal access, Miami, USA, September 2013

Waldir Moreira, Manuel de Souza, Paulo Mendes, Susana Sargento, "Study on the Effect of Network Dynamics on Opportunistic Routing", in Proc. of AdhocNow, Belgrade, Serbia, July 2012

Waldir Moreira, Paulo Mendes, Susana Sargento, "Opportunistic Routing based on daily routines", in Proc. of IEEE WoWMoM workshop on autonomic and opportunistic communications, San Francisco, USA, June, 2012

Waldir Moreira, Paulo Mendes, Susana Sargento, "Assessment Model for Opportunistic Routing", in Proc. of IEEE Latincom, Belem, Brazil, October 2011

Waldir Moreira, Paulo Mendes, "Routing Metrics for Delay Tolerant Networks", In Proc. of CRC 2010, Braga, Portugal, November 2010

Standardisation Drafts

W. Moreira, P. Mendes and E. Cerqueira, “Opportunistic Routing based on Users Daily Life Routine”, IETF Internet Draft (draft-moreira-dlife-04), May 2014


SCORP (2013): Social-aware Content-based Opportunistic Routing Protocol. ONE simulator module. (Authors: Waldir Moreira, Paulo Mendes). Developed in the DTNAmazon project. SITI-SW-13-01

SocialDTN (2013): DTN module for Android based on social-aware opportunistic routing over bluetooth (Authors: Ronedo Ferreira, Douglas Cirqueira, Waldir Moreira, Paulo Mendes). Developed in the DTNAmazon project.

dLife V2.0 (2012): Opportunistic Routing based on Social Daily Routines. ONE simulator module. (Authors: Waldir Moreira, Paulo Mendes). Developed in the DTNAmazon and CitySense project. SITI-SW-12-02, 2012

Technical Reports

Waldir Moreira and Paulo Mendes, Social-aware Opportunistic Routing Solutions, SITILabs, University Lusófona, number SITI-TR-13-01, 2013

Waldir Moreira and Paulo Mendes, Structural Analysis of Social-aware Opportunistic Networks, SITILabs, University Lusófona, number SITI-TR-13-05, 2013

Namusale Chama, Waldir Moreira, Antonio Oliveira Junior, Marilia Curado, Vítor Rola and Paulo Mendes, UCR D3: Routing for User-provided Networks, SITILABS / University Lusofona; University of Coimbra, number SITI-TR-13-03, 2013

Waldir Moreira and Paulo Mendes, Social-aware Utility Functions for Opportunistic Routing, SITI, University Lusófona, number SITI-TR-12-05, 2012