"Traditional cryptography emphasizes on the design of cryptosystems, instead of the concrete implementation. However, the emerging 

side-channel attacks, allow the adversary to gain internal secret information of a cryptographic system, and renders many cryptosystems that are designed to be secure not secure any more. To resist these attacks, researchers proposed the notion of leakage-resilient cryptography and constructed corresponding cryptosystems, in order to fill in the security gap caused by information leakage. However, these schemes either torelate leakage of only a small fraction of the secret informaiton, or put restrictions on the type of leaked information, or are very complicated and 

thus not practically efficient. In this project we will investigate the construction of digital signature in the leakage resistant setting, which is an important cryptographic primitive. We will study the construction of leakage resistant signature schemes with high leakage ratio and better efficiency, as well as new approach to constructing this primitive. We will also investigate how to build leakage resistant signature schemes with adaptive security under more generic leakage model, for example, the auxiliary input model. Second, we will study the common variants of signatures, introduce the notions of leakage resistant group signature and ring signature, and propose their constructions. Furthermore, as identity-based encryption can be used to construct signature schemes, we will also investigate its construction, trying to improve the efficiency and leakage ratio."