Intelligent Networks and Security

Selected publications:

WebSocket protocol is a part of HTML5 standard, which is suitable for real-time and full duplex web applications such as online chat, notification server, and online game systems. A compression algorithm for WebSocket protocol has yet to be defined as a standard. There is a proposal to use Deflate algorithm, a lossless compression algorithm for WebSocket, but other compression algorithms are also available.
In this paper, Deflate algorithm is compared with other lossless algorithms, i.e. Huffman, LZ77 and LZW algorithms in order to find a suitable compression algorithm for WebSocket protocol. A compression library is developed using JavaScript for studying and analyzing such compression algorithms for different data formats. In addition, an instant messaging system and an online game are developed and studied as the examples of WebSocket real-time and full duplex web applications. The performance metrics for this study are a compression ratio, compression and decompression speeds and overall time. In our experiments, the deflate compression algorithm gains the best result in terms of overall time and compression ratio for WebSocket protocol.

status:
student:
Chanapa Silawong (Thesis)

In a disaster hit area, infrastructure networks may be disconnected and main communications between victims and rescuers are not available. An interesting question is that how many people are trapped in a collapsed building and how close they are to a nearby rescuer’s position. A smart-phone is widely used today and it normally has a Wi-Fi function to connect to the Internet. The phone can be used for saving victims’ lives. In this paper, a communication model is proposed for a victim to communicate with others and also a rescuer to communicate with victims. State diagrams of the victim and rescuer models are proposed along with pseudo codes for the model operation. An example communication scenario is presented to demonstrate how the model works.

Selected publications:
status:
Finished
student:

Elliptic Curve Cryptography (ECC) gains attention due to the security efficiency with lower computational cost for mobile devices. However, the security achievement for ECC depends on the encoding process to transform a plaintext into a point or more on an elliptic curve. In this work, we propose an encoding method based on a dynamic point encoding. A character is encoded depending on two factors: its sequence and its ASCII value. This technique ensures against frequency cryptanalysis. We also compare our work with the existing encoding techniques in various dimensions such as computational complexity, time, resource, and security constraints. Dynamic point encoding technique consumes less memory storage than other dynamic encoding techniques while the computational complexity is equal to O(N).

Selected publications:
status:
Finished
student:

This paper focuses on enhancing a username and password authentication scheme, which has some weaknesses because a username is publicly known and a password can be guessed. When an attacker knows or guesses a password correctly, the system is compromised. Therefore, this research focuses on this weakness and proposes an additional security token to this scheme by combining keystroke dynamics into the system. A username is typically not changed but a password is required to change frequently for a better security level. A username is typed frequently such that the familiar typing can be used as a behavioral biometrics of a user. Therefore, a keystroke dynamics profile is proposed using a trajectory dissimilarity technique to verify user’s typing behavior on a username as an additional authentication token. Several features are mined for keystroke dynamics to create a trajectory profile, which gives the best results of 4% equal error rate (EER) or 96% authentication accuracy.

Selected publications:
status:
Finished
student:
Kasem Wangsuk (Thesis)