anonymous signature implementation and usage?

Question

This is one of the question asked in my class. Implement a anonymous digital signature. So it means hiding signers information. i could not find any article in anonymous digital signing. Also another confusion made me think about blind signature. blind signature used to hide senders information before sign by a third party. This scheme is not going to hide sender identity. For my knowledge group signature can be used hide the identity of sender. My question is

• what is anonymous digital signature
• How it different from blind signature
• How can we use this to hide identity of sender

Answer 1

The first google-entry brought up this paper. To answer your questions:

1. An anonymous signature is a signature that is unforgeable in the classic sense. But without the message no informations about the signer can be extracted from the signature even if brute-force of all public keys is possible.
2. If I'm understanding things correctly, a blind signature hides the message from the signer but the signer is still known. So the signer is not anonymous whereas with anonymous signing the signer is anonymous as long as the message is unknown, but the signer knows what he's signing. (I hope that makes sense)
3. The paper will give you insight in how to actually implement anonymous signature.

You may also wish to read this paper and maybe even some references to get further ideas. In the mentioned paper there's an approach the anonymize the signer by holding back parts of the signature.