Towards mobile cryptography

Abstract

Mobile code technology has become a driving force for recent advances in distributed systems. The concept of mobility of executable code raises major security problems. In this paper we deal with the protection of mobile code from possibly malicious hosts. We conceptualize on the specific cryptographic problems posed by mobile code. We are able to provide a solution for some of these problems: We present techniques how to achieve "non-interactive evaluation with encrypted functions" in certain cases and give a complete solution for this problem in important instances. We further present a way how an agent might securely perform a cryptographic primitive, digital signing, in an untrusted execution environment. Our results are based on the use of homomorphic encryption schemes and function composition techniques.

Classification and Review of Security Schemes in Mobile Computing

“…With the help of mobile agents it is possible to create distributed applications where the programs can autonomously traverse from one computer to another and get executed. They are more powerful than an ordinary applets [21] due to the AI component, they decide themselves where and when to traverse and execute. They are prominently applied in mobile computing systems.…”

“…"Mobile software agents are very useful in this context, since they could encapsulate long-lasting transactions. They could carry a request to server, cause its execution and bring back the result as soon as the connectivity is reestablished [21]." Due its ability to preprocess the results, it makes use of the slow communication link between the mobile device and the network.…”

Secure Meeting Scheduling with Agenta

“…This host has to be trusted as long as the agents cannot be protected from it. The execution of encrypted functions [6] has the potential to protect agents from hosts they run on, and e.g., allow them to digitally sign messages on untrusted platforms.…”

Abstractions for Mobile Computation

“…Although a great deal of cryptographic technology is available, there might be impossibility results lurking in some corners. For example, it is far from clear whether one can in principle guarantee the integrity of mobile computations against hostile or unfair servers [33]. (This can be solved on a LAN by having all computers under physical supervision.)…”