Asset-backed securities are developed through complex processes such as asset restructuring and credit enhancement.Therefore,the information asymmetry between issuers and investors is greater compared to traditional s...Asset-backed securities are developed through complex processes such as asset restructuring and credit enhancement.Therefore,the information asymmetry between issuers and investors is greater compared to traditional securities,which imposes higher requirements on information disclosure for asset-backed securities.Asset-backed securities have characteristics such as diversified disclosers,differentiated disclosure content,and specialized risk factors.China has already formulated a series of rules and regulations regarding information disclosure of asset-backed securities.It is imperative to develop specialized laws and regulations for asset-backed securities,encompass original equity holders and credit enhancement agencies as information disclosers,incorporate information such as underlying asset details,cash flow projections,and credit ratings and enhancements into the disclosure content,and improve the legal liability rules to effectively address false disclosures.展开更多
Attribute revocation is inevitable and also important for Attribute-Based Encryption (ABE) in practice.However,little attention has been paid to this issue,and it remains one of the main obstacles for the application ...Attribute revocation is inevitable and also important for Attribute-Based Encryption (ABE) in practice.However,little attention has been paid to this issue,and it remains one of the main obstacles for the application of ABE.Most of existing ABE schemes support attribute revocation work under indirect revocation model such that all the users' private keys will be affected when the revocation events occur.Though some ABE schemes have realized revocation under direct revocation model such that the revocation list is embedded in the ciphertext and none of the users' private keys will be affected by revocation,they mostly focused on the user revocation that revokes the user's whole attributes,or they can only be proven to be selectively secure.In this paper,we first define a model of adaptively secure ABE supporting the attribute revocation under direct revocation model.Then we propose a Key-Policy ABE (KP-ABE) scheme and a Ciphertext-Policy ABE (CP-ABE) scheme on composite order bilinear groups.Finally,we prove our schemes to be adaptively secure by employing the methodology of dual system encryption.展开更多
文摘Asset-backed securities are developed through complex processes such as asset restructuring and credit enhancement.Therefore,the information asymmetry between issuers and investors is greater compared to traditional securities,which imposes higher requirements on information disclosure for asset-backed securities.Asset-backed securities have characteristics such as diversified disclosers,differentiated disclosure content,and specialized risk factors.China has already formulated a series of rules and regulations regarding information disclosure of asset-backed securities.It is imperative to develop specialized laws and regulations for asset-backed securities,encompass original equity holders and credit enhancement agencies as information disclosers,incorporate information such as underlying asset details,cash flow projections,and credit ratings and enhancements into the disclosure content,and improve the legal liability rules to effectively address false disclosures.
文摘Attribute revocation is inevitable and also important for Attribute-Based Encryption (ABE) in practice.However,little attention has been paid to this issue,and it remains one of the main obstacles for the application of ABE.Most of existing ABE schemes support attribute revocation work under indirect revocation model such that all the users' private keys will be affected when the revocation events occur.Though some ABE schemes have realized revocation under direct revocation model such that the revocation list is embedded in the ciphertext and none of the users' private keys will be affected by revocation,they mostly focused on the user revocation that revokes the user's whole attributes,or they can only be proven to be selectively secure.In this paper,we first define a model of adaptively secure ABE supporting the attribute revocation under direct revocation model.Then we propose a Key-Policy ABE (KP-ABE) scheme and a Ciphertext-Policy ABE (CP-ABE) scheme on composite order bilinear groups.Finally,we prove our schemes to be adaptively secure by employing the methodology of dual system encryption.