Security in a mobile communication environment is always a matter for concern, even after deploying many security techniques at device, network, and application levels. The end-to-end security for mobile applications can be made robust by developing dynamic schemes at application level which makes use of the existing security techniques varying in terms of space, time, and attacks complexities. In this paper we present a security techniques selection scheme for mobile transactions, called the Transactions-Based Security Scheme (TBSS). The TBSS uses intelligence to study, and analyzes the security implications of transactions under execution based on certain criterion such as user behaviors, transaction sensitivity levels, and credibility factors computed over the previous transactions by the users, network vulnerability, and device characteristics. The TBSS identifies a suitable level of security techniques from the repository, which consists of symmetric, and asymmetric types of security algorithms arranged in three complexity levels, covering various encryption/decryption techniques, digital signature schemes, and hashing techniques. From this identified level, one of the techniques is deployed randomly. The results shows that, there is a considerable reduction in security cost compared to static schemes, which employ pre-fixed security techniques to secure the transactions data.tems lack dynamic security policies, and enforcement mechanisms that could make them more flexible, and appealing to users. Dynamic security architectures are required for mobile computing, to allow the frequent migration of computers in, and out of security domains, in order to create dynamic sessions across organizations. Also, the traditional security models usually work according to a static decision-making approach, i.e., irrespective of the sensitivity of transactions going on, they employ common security technique to secure RANDOM SECURITY SCHEME SELECTION 695 the entire session, which increases the cost of security in terms of processing, and signaling load introduced by cryptography algorithms. To overcome this, it is required to have an application oriented security scheme which implements dynamic selection, and execution of security techniques. In present day mobile communications there is a requirement to select dynamically, the existing security techniques based on transactions sensitivity levels, and usage context, since most of noncritical information such as product promotion materials, general product details, and so on, do not need any security or needs less security.As mentioned earlier the traditional security schemes are session-based mechanisms, commonly works with pre-fixed security techniques based on the types of transactions. Most commonly they prefer high security to financial transactions over non-financial transactions. In any service scenario, we can identify range of transactions which varies on the associated risk levels. For example, for a banking application, money transfer transaction in a intra-domain...