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The Better Approach To Mobile Adhoc Networking (B.A.T.M.A.N.) is a routing protocol for multi-hop ad hoc networks which is under development by the "Freifunk" community and intended to replace OLSR. It can be used for mesh networks but this is not the only potential use. B.A.T.M.A.N.'s crucial point is the decentralization of the knowledge about the best route through the network — no single node has all the data. This technique eliminates the need to spread information concerning network changes to every node in the network. The individual node only saves information about the "direction" it received data from and sends its data accordingly. The data gets passed on from node to node and packets get individual, dynamically created routes. A network of collective intelligence is created. In early 2007, the B.A.T.M.A.N. developers started experimenting with the idea of routing on layer 2 (Ethernet layer) instead of layer 3. To differentiate from the layer 3 routing daemon, the suffix "adv" (for: advanced) was chosen. Instead of sending UDP packets and manipulating routing tables, it provides a virtual network interface and transparently transports packets on its own. The batman-adv kernel module has been part of the official Linux kernel since 2.6.38. 〔(Linux 2 6 38 Linux Kernel Newbies )〕 == Operation == B.A.T.M.A.N. does have elements of classical routing protocols: It detects other B.A.T.M.A.N. nodes and finds the best way (route) to these. It also keeps track of new nodes and informs its neighbors about their existence. In static networks, network administrators or technicians decide which computer is reached via which way or cable. As radio networks undergo constant changes and low participation-thresholds are a vital part of the "Freifunk"-networks' foundation, this task has to be automated as much as possible. On a regular basis, every node sends out a broadcast, thereby informing all its neighbors about its existence. The neighbors then relay this message to their neighbors, and so on. This carries the information to every node in the network. In order to find the best way to a certain node, B.A.T.M.A.N. counts the originator-messages received and logs which neighbor the message came in through. Like distance-vector protocols, B.A.T.M.A.N. does not try to determine the entire route, but, by using the originator-messages, only the packet's first step in the right direction. The data is handed over to the next neighbor in that direction, which in turn uses the same mechanism. This process is repeated until the data reaches its destination. In addition to radio networks, B.A.T.M.A.N. can also be used with common cable connections, such as Ethernet. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「B.A.T.M.A.N.」の詳細全文を読む スポンサード リンク
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