Research On DEM Disguise And Integrity Authentication Algorithm

Digital Elevation Model(DEM)is an indispensable strategic resource in national economic development and national defense construction,and it has a very wide range of applications in military,territorial,surveying,mapping,geology and other fields.DEM,which accuracy are high,has the characteristics of accurate positioning.Once leaked,it will pose a serious threat to national and national defense security.Under the background of the Internet,the development of geographic information service platforms has become more and more mature,which has brought great convenience to data sharing.However,at the same time,disaster emergency command and other occasions have increasingly higher requirements for data sharing timeliness.As a result,the demand for DEM's network sharing services is increasing day by day,and its security issues are becoming increasingly prominent.Using reliable technical means to protect the security of DEM,especially in the network environment,is particularly important to protect its concealment and integrity.Information disguise technology is a mature information security technology.It disguises confidential information that needs protection into non-confidential information.It has the characteristics of strong concealment.It is a powerful means of protecting DEM's security,but it cannot protect the integrity of DEM.Integrity authentication technology can verify the integrity of DEM's disguised data,and can effectively verify whether DEM's disguised data is complete after transmission.This article studies different DEM disguise strategies for DEM's security protection needs.Based on the information disguise technology,two DEM disguise algorithm for different scenarios are studied,and the integrity authentication technology is used to protect the integrity of the DEM's disguised data.The main contents and conclusions of the study are as follows:(1)Based on the analysis of the file structure,spatial distribution,application and network transmission's security requirements of DEM,the principles of security,concealment,reversibility and verifiability that DEM disguise algorithms need to follow are established,and then propose different disguise strategies for different scenarios for the safe of DEM's networks transmission,which establishes the research foundation for this article.(2)Aiming at the risk of leakage of DEM,a DEM disguise algorithm based on scrambling of characteristic elevation values is proposed.The location tag template is used to achieve scrambling of the designated bit of the elevation value,the disturbance to the elevation value is small,and the concealment of the camouflage operation is high,which can reduce the suspicion of data by potential attackers.Experiments show that DEM's disguised data has a high similarity to the original DEM.In the scenario where a potential attacker wants to intercept and apply the data,DEM's security is protected and a preview function is provided.(3)Aiming at the sensitivity of DEM during network transmission,a DEM disguise algorithm based on re-encoding and steganography is proposed to disguise a DEM into an image data not related to the original DEM at all.The concealment in transmission avoids the attention of potential attackers.Experiments show that the algorithm has good concealment and can reduce the amount of data that needs to be transmitted.In the scenario where a potential attacker only wants to interfere with the transmission process,DEM's security is protected.(4)Based on the statistical characteristics of DEM's disguised data,the integrity authentication technology is applied to DEM's disguised data,and a reversible digital watermarking algorithm based on histogram translation is proposed.The algorithm takes the digest of DEM's disguised data as authentication information,uses the zero value point used to restore DEM's disguised data as record information,and combines them together into watermark information.Experiments show that the algorithm can achieve the tampering and positioning of the block accurately without recording additional information,and can recover the DEM's disguised data that passed the authentication without loss.