Improvement Of A Structured Multi-Signature Scheme

Structured multi-signatures is a special multi-signature which multiple signer can sign the same message and it provided co-signers with different position have different authorization capability. There are lots of structured multi-signature schemes such as Ham's scheme and Burmester's scheme, etc. Though Ham's scheme was relatively safer, yet this scheme was not safety enough because it was very easily aggressed by the forgery attack. This paper shows the scheme can not resist the forgery attack. Then the paper proposed a new structure multi-signature scheme based on the difficulty of the discrete logarithm problem with verifying signature parameter and signers' public keys. By verifying public-key, the new scheme can resist lots of outsider attack and insider attack. The validity of the new scheme can be verified, and it is a secure structured multi-signature scheme.