# E-SAWM: A Semantic Analysis-Based ODF Watermarking Algorithm for Edge Cloud Scenarios
## 2 Related Work
### Document Watermarking Techniques
The field of watermarking in the context of OFD has received limited attention in both academia and industry[PERSON] In academia, there is a noticeable dearth of research studies and published papers specifically dedicated to OFD watermarking. On the industry front, existing OFD watermarking techniques primarily rely on explicit watermarks, which are implemented based on the following principles:  
The watermark text content, along with relevant information such as position, transparency, size, and color, is defined within the annotation structure file named Annotation.xml[PERSON] This file is an integral part of the internal structure of the OFD file and is typically located in the Annots/Page_n folder. The details of watermark addition are depicted in Figures 4 and 5. \begin{table}
\begin{tabular}{c c} \hline \hline
**FLIE/FOLDER** & **Description** \\ \hline OFDxml & OFD file main entry file; describes the basic \\ \multirow{2}{*}{Doc\_N} & OFD file information \\  & The Nth document folder \\ \multirow{2}{*}{Doc\_N folder description file, including} & Doc\_N folder description file, including \\  & information about subfiles and subfolders \\ \multirow{2}{*}{Documnt.xml} & contained under Doc\_N \\  & The Nth page folder \\ \multirow{2}{*}{Page\_N Content.xml} & Content description on page N \\  & Resource description on page N \\ \multirow{2}{*}{Res} & Resource folder \\ \multirow{2}{*}{PublicRes.xml} & Document public resources index \\ \multirow{2}{*}{DocumentRes.xml} & Document own resource index \\  & Image\_M.png/Font\_M.ttf & Resource files \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Internal Structural file description of OFD. In addition to the advantages of data sharing, the prevention of data leakage has emerged as a growing concern. Currently, most bankcryp on contractal agreements to enforce compliance and security measures during the transmission and utilization of data by application parties, lacking sufficient technical support. In cases of data leakage within the application scenario, banks encounter difficulties in promptly and accurately assigning responsibility to the relevant application parties, resulting in detrimental consequences for customers' banks, and the overall financial system. Given the increasing openness of the scenario ecosystem, relying solely on contractal agreements becomes increasingly challenging for banking institutions to mitigate risks associated with data sharing. It is imperative to incorporate additional technical support to fortify data security measures and enable effective prevention and monitoring of data security risks. The integration of watermarks in OFD files plays a crucial role in ensuring timely traceability and accountability following instances of data leakage. Although the structure of the watermark may seem clear and straightforward, it is susceptible to various attacks. Adversaries have the ability to manipulate the Annotation.xml folder, leading to vulnerabilities in the watermark's integrity, decryption, and identification, with potential for malicious removal. Consequently, the task of tracing compromised data becomes significantly challenging.