The Research On Routing Protocols Based On Nodal Sociality In Opportunistic Networks

Opportunistic networks are a self-organizing network that requires not to continuously maintain a complete communication link between nodes and its nodes catch the meeting opportunity to forward messages.Most of nodes in opportunistic networks are wireless smart terminal devices configuring Wi-Fi or bluetooth interface carried or controlled by people,and these devices encounter randomly to achieve information interaction.People's social behavior is regular,which is determined by social attributes.Considering social attributes in the process of studying routing policy improves network performance well in opportunistic networks.The paper analyses existing message transfer protocol HBPR(A Social Relations Based Routing Protocol for Low Time Delay in Opportunistic Networks) and SGBR(A Routing Protocol for Delay Tolerant Networks Using Social Grouping).The study ulteriorly finds questions that HBPR has interactive information redundancy and unsuitably selects forwarding nodes,and SGBR also exists that nodes backlog allocation task and number of message copies is allocated unreasonably.In order to solve the above questions of HBPR and SGBR,the paper proposes two improved algorithms based on these two protocols:A Social Relations Based Routing Protocol for Low Time Delay in Opportunistic Networks-SRBRPLTD and A Social Grouping Based Routing Protocol for High Delivery Rate in Opportunistic Networks-SGBRHDR.According to updated time recorded and the two nodes' last meeting time,SRBRPLTD select these related information recorded after the two nodes' last meeting time to be transferred to meeting node.When transferring messages between nodes owned different home location cells,node carried message firstly selects nodes having relations with destination node' s home location cell to transmit messages;when transmissing messages in single home location cell,adopts “copy-transfer” mode.In SGBRHDR,firstly,dividing social groups distributedly.Secondly,message copies are transferred within single social group or among social groups.when transferring messages between social groups,according to activity rate with encounter node,node carried multiple messages reasonably allocates copy number to encounter node;when transferring messages in a single social group,taking average social relationship strength value with destination node as transfer measure value,messages always transfer along the direction of the bigger average social relation strength value.The paper uses ONE simulation tool to model above protocols.The results show,the performance of message delivery success rate and average transfer time delay in SRBRPLTD and SGBRHDR is all improved significantly.Finally,concluding circle and on this basis noting the future work.