机会网络中高效低时延多摆渡节点路由算法

An Efficient and Low-Delay Routing Algorithm for Multiple Ferries in Opportunistic Networks

针对机会网络中带网关节点的多摆渡节点路由算法(MMFGW)存在部分区外消息冗余等待、数据转发次数偏多和相邻区摆渡节点之间无协作的情况,提出了一种新的多摆渡高效低时延路由算法(ERMF)。当网关节点的邻居节点有数据发送时,ERMF算法通过查询跨层旁听机制建立区外属性表,确认表中有匹配,则数据不再经过本地摆渡节点转发,而是向网关节点直传。另外,跨区域摆渡节点之间相遇时,通过彼此交换自己区域内的节点信息获取属于本区域内的有效数据,这2种直接通信的协作机制均可优化节点间单一的数据交互方式,促进区域间数据的快速传输,在不影响原有数据传输功能的前提下降低数据分组时延和转发开销。仿真结果表明,与MMFGW算法和节点中继算法相比,ERMF算法的数据分组转发开销和平均端到端时延分别降低了8.1%和7.3%以上。

An efficient and low-delay routing algorithm based on multiple ferries（ERMF）is proposed to address the problems that appear when the multiple message ferries gateway-based algorithm（MMFGW）is applied to opportunistic networks,such as some outside information redundancy is waiting for transfer,the number of data forwarding is a little large,and there is no collaboration among neighboring regions.When the neighbor nodes of a gateway node have data to send,the ERMF algorithm makes a decision through querying an attribute table of outside regions,which is established based on a cross-layer overhearing mechanism.If there exists a match in the table,the data is directly transferred to the gateway instead of forwarding through a local ferry node.When the ferries between the two regions are encountered,each ferry obtains valid data in its own region through exchanging information of nodes in their own regions.These two coordination mechanisms of direct communication optimize the single data interaction mode,realize fast data transmission between two regions,and reduce the delay and cost of data forwarding without affecting the function of original data transmission.Simulation results andcomparisons with the MMFGW and the node relaying algorithm show that the proposed ERMF reduces the forward overhead and the average end-to-end delay of packets by about 8.1% and7.3%,respectively.