In the multicast network, network coding has proven to be an effective technique to approach maximum flow capacity. Although network coding has the advantage of improving performance, encoding nodes increases the cost and delay in wireless networks. Therefore, minimizing encoding nodes is of great significance to improve the actual network’s performance under a maximum multicast flow. This paper seeks to achieve partial improvements in the existing selection algorithm of encoding nodes in wireless networks. Firstly, the article gives the condition for an intermediate node to be an encoding node. Secondly, a maximum flow algorithm, which depends on the depth-first search method, is proposed to optimize the search time by selecting the larger augmentation flow in each step. Finally, we construct a random graph model to simulate the wireless network and the maximum multicast flow algorithm to analyze the statistical characteristics of encoding nodes. This paper aims at the optimization to find the minimal number of required coding nodes which means the minimum energy consumption. Meanwhile, the simulations indicate that the curve of coding nodes tends to be a geometric distribution, and that the curve of the maximum flow tends to be symmetric as the network scale and the node covering radius increase.

中文翻译：

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移动无线网络中用于网络编码的节点选择算法

在多播网络中，网络编码已被证明是一种实现最大流量的有效技术。尽管网络编码具有提高性能的优点，但是编码节点增加了无线网络的成本和延迟。因此，最小化编码节点对于提高最大组播流量下实际网络的性能具有重要意义。本文力求对无线网络中现有的编码节点选择算法进行部分改进。首先，本文给出了中间节点成为编码节点的条件。其次，提出了一种基于深度优先搜索方法的最大流算法，通过在每个步骤中选择较大的增强流来优化搜索时间。最后，我们构建了一个随机图模型来模拟无线网络，并构造了一个最大组播流算法来分析编码节点的统计特性。本文旨在优化以找到所需编码节点的最小数量，这意味着最低的能耗。同时，仿真表明，编码节点的曲线趋于呈几何分布，并且随着网络规模和节点覆盖半径的增大，最大流量的趋向于趋于对称。