# The YouGovern Secure Blockchain-Based Self-Sovereign Identity (SSI) Management and Access Control
## 2 Background Theory and Related Works
### Related Work
\begin{table}
\begin{tabular}{c c c} \hline
**Specifications** & **uPort** & **Sovrin** \\ \hline Sovereignty & uPort is a SSI & Sovrin is a SSI \\ \hline \multirow{4}{*}{Storage control} & Identity and its associated & Identity and its associated \\  & confidential/personal information are & confidential/personal information are \\  & maintained in the Digital Wallet at the & maintained in the Edge Wallet at the Edge \\  & owner’s device end & Agent device of the owner. They can be also \\  & & maintained in a Cloud Wallet at a Cloud \\  & & Agent device (safeguarded from \\  & & unauthorized accesses) \\ \hline \multirow{4}{*}{Recovery} & Based on DIDs & Based on DIDs \\  & & \\ \cline{1-1}  & \multirow{4}{*}{Based on Verifiable Credentials (VCs)} & \multirow{4}{*}{Based on VCs} \\ \cline{1-1}  & \multirow{4}{*}{Social recovery approach—Recovery} & Social recovery approach—Recovery Key \\  & delegates denoted by the identity owner (e.g., & Trustees, who are trusted by the identity \\ \cline{1-1}  & selected organizations, friends, family & owner, can store recovery information on \\ \cline{1-1}  & members, etc.) can assist the user to regain & their agents on behalf of the owner and assist \\  & his/her uPort identity & him/her recovering the identity. \\ \hline \multirow{4}{*}{Cost-free} & Currently, identity is free for a user. & Currently, identity is free for a user. Also, \\  & Nevertheless, all transactions impose an & there is no additional costs for \\  & inherent cost. & identity transactions. \\ \hline \multirow{4}{*}{Security} & Password/PIN and biometry are demanding & Password/PIN and biometry are demanding \\  & for the identity control via the blockchain. A & for the identity control via the blockchain. A \\ \cline{1-1}  & user can securely publish his/her identity, as & user can securely publish his/her identity, as \\ \cline{1-1}  & well as control his/her data, sign transactions, & well as control his/her data with powerful \\ \cline{1-1}  & & and transfer his/her credentials. \\ \hline \multirow{4}{*}{Privacy} & uPort is privacy preserving. A user does not & Sovrin provides privacy-by-default and \\ \cline{1-1}  & have to disclose personal data to establish & privacy-by-design. It utilizes anonymous \\ \cline{1-1}  & uPort footprints several mechanisms to limit & credentials based on ZKPs that enable a user \\ \cline{1-1}  & the correlation of a user’s on-chain smart & to disseminate data which retain the \\ \cline{1-1}  & contract transaction among different dapps. & users’ anonymity \\ \hline \multirow{2}{*}{Safeguard} & Users’ right to privacy has to be safeguarded & Users’ right to privacy has to be safeguarded \\ \hline \multirow{4}{*}{Accessibility} & uPort is easy-to-use and has a simple design & Sovrin exhibits a complex design architecture, \\ \cline{1-1}  & architecture. Currently, there is no provision & with several users requiring a Guardian to \\ \cline{1-1}  & for a relevant Agent/Guardian & control the identity on their behalf \\ \hline \end{tabular}
\end{table} 
Table 1: Correlation between uPort and Sovrin. The new IDM 3.0 framework needs to be carefully evaluated for its various aspects. [PERSON] suggested the Ten Principles for SSI [43], which provided an implementation framework for the concept of self-supreme identity. Furthermore, as shown in Table 2, the Sovrin Foundation [38] grouped in a white paper three categories: security, monitoring, and portability. However, in this sense, persistence does not interfere with [PERSON]'s \"right to be forgotten\". It may as well be listed separately since control and consent must be created, as well as access and removal of identity. Domain Name System-Identity Management (DNS-IdM) [44] is a scheme of Identity Management based on smart contracts. This helps users preserve their identities related to distinctive characteristics, achieving the self-sovereign concept. With respect to protection and privacy, DNS-IdM has promising results [44].