Many of the signature schemes are proposed in which the t out of n threshold schemes are deployed; but they still lack the property of security. In this paper, we have discussed implementation of improved CCH1 and improved CCH2 proxy multi-signature scheme based on elliptic curve cryptosystem. We have represented time complexity, space complexity and computational overhead of improved CCH1 and CCH2 proxy multi-signature schemes. We have presented cryptanalysis of improved CCH2 proxy multi-signature scheme and showed that improved CCH2 scheme is suffered from various attacks i.e. forgery attack and framing attack.

Due to internet expansion web applications have now become a part of everyday life. As a result a number of incidents which exploit web application vulnerabilities are increasing. A large number of these incidents are SQL Injection attacks which are a serious security threat to databases which contain sensitive information, the leakage of which cause a large amount of loss. SQL Injection Attacks occur when an intruder changes the query structure by inserting any malicious input. There are a number of methods available to detect and prevent SQL Injection Attacks. But these are too complex to use. This paper proposes a very simple, effective and time saving technique to detect SQLIAs which uses combined static and dynamic analysis and also defines an attack other than existing classification of SQLIAs.

An efficient threshold signature scheme solves the difficulties of the receiver to proof the approval of the document from the sender as well as detecting if the file has been altered by illegitimate parties. In these days there are plenty of signature schemes such as (t,n) threshold proxy signature scheme. The network is a shared medium so that the weakness security attacks such as eavesdropping, replay attack and modification attack. Thus, we have to establish a common key for encrypting/decrypting our communications over an insecure network. In this scheme, a (t,n) threshold proxy signature scheme based on RSA, any t or more proxy signers can cooperatively generate a proxy signature while t-1 or fewer of them can't do it. The threshold proxy signature scheme uses the RSA cryptosystem to generate the private and the public key of the signers. Comparison is done on the basis of time complexity, space complexity and communication overhead. We compare the performance of four schemes: Hwang et al., Wen et al., Geng et al. and Fengying et al. with the performance of a scheme that has been proposed by the authors of this article earlier. In the proposed scheme, both the combiner and the secret share holder can verify the correctness of the information that they are receiving from each other. Therefore, the enhanced threshold proxy signature scheme is secure and efficient against notorious conspiracy attacks.