This paper analyses several typical data-frames of wireless communication, proposes an algorithm of data-frame recognition, which is based on tagged word of data-frames, and analyses the performance of algorithm. This paper resolves problems of protocol type analyzing and data frame recognizing, which are for date link layer (DDL) of wireless communication, by the algorithm of data-frame recognition. Introduction: Along with the popularization and application of network, the network protocols

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... so emerge in endlessly. Data can only be transmitted on the network after being packaged as packets based on certain agreement format. In the aspect of network confrontation, especially the wireless network, data are mainly obtained through the interception of the link of wireless network. While protocol type and data link layer frame can't be directly obtained from network devices, so the analysis of the protocol and the identification of data frame must be done for acquiring these parameters. At present, the analysis technology for upper level protocol has been quite mature, some of the most famous software and hardware are ethereal, Sniffer, airpcap and so on [1]. But for there is almost no analysis algorithm or product for bit information obtained through demodulation and decoding directly from the physical layer. Therefore the protocol analysis and data frame identification algorithm is one of the most important ways to improve the ability of electronic warfare on battlefield information network [2]. In this paper, the protocol analysis for DDL is to achieve filtering and identification on bit information of DDL which is intercepted from the network, and then to discriminate protocol type. The identification of data frame is also for filtering and recognition of the intercepted bit information, getting a different type of protocol packet, then obtaining the upper protocol type through the further interpretation of packet. Hence the recognition of the data frame on link layer is the basis of the parsing of upper protocol [3]. The analysis of DDL protocol and identification of data frame on wireless communication are mainly studied in this paper; three typical wireless communication systems such as AIS and ACARS, WLAN are selected for the analysis. In this paper, the data acquisition method is introduced firstly, which is the basis of identification; Then the analysis research is done on the data frames of the three typical protocols; a recognition algorithm of data frame is put forward; the performance of the algorithm analysis, experimental results and conclusions are given at last. Design and realization of the algorithm: A. Recognition Basis of Data Frame Wireless network is the collection constituted by many independent communication nodes which are linked with each other through wireless communication channels; its basic elements can be divided into network nodes and communications channels. The basis of identification data on wireless DDL is to demodulate data successfully and obtain bit stream by channel decoding. In this paper, the post-mortem analysis and processing are only done on DDL, without considering the