Wireless Adhoc Network Service Discovery Mechanism Of Realization

AdHoc is a kind of temporary wireless multi-hop communication network which is consist of numbers of wireless mobile nodes,and do not rely on any foundational communcation facilities.Each node in this type of network works as an ordinary node as well as a wireless router.It is popular in network research. It allows mobile nodes to spontaneously form a network and share their services. There are many achievements in the routing layer, data link layer and physical layer of AdHoc. Since nowadays it is used in wide areas, So not only data transmission but also various network services should be offered by AdHoc. It is necessary to set a management system on network services in it.The Service Discover Protocol is a technique with which the nodes in AdHoc search for the services they want.So a simple and efficient,robust and flexible Service Discover Protocol as well as good scalability is a significient technique of AdHoc.First,I describe the current situation of the SDP(Service Discover Protocol)in the wireless AdHoc network,and the basic principle of AdHoc network,Then I put forward the target network on which I work. I analyze the structure of the target network and put forward the design ideas and scheme for the SDP based on the target network.i modularize the protocol to four parts and carry them out separately. At the same time, I design the message format and the databases related to the SDP.The SDP in this thesis has choised the sub-group mechanism. Some relatively powerful nodes were choised to become the cluster head node and manage the Service Discovery operations concentrately. These cluster heads compose the backbone network which deal with the service discovery operations of the whole network distributely. The emphases of the design of SDP is how to implement the Service Discovery. It can be departed into two parts,in-group inquiry and global inquiry. The global inquiry has used two different mechanism,one is based on the reomte database connection,the other is based on the index files.The latter one has made use of the open-source software Lucene which is a full-text index API. The thesis dilate the two kinds of global inquiry mechanism and then explained how to implement them.The programming language is Java ,the platform is Linux. Finally,I carry out the functionality and performance testing of the SDP under the circumstance of the target network.