M.Sc.

Computer network technologies have grown rapidly in the last few decades. With the increased use of networked computers for critical applications, computer intrusions have been increased and became a significant threat to these systems and, thus Intrusion Detection Systems (IDS) have become essential addition to security infrastructure of most organizations.This thesis presents the design and plementation of a Network Node Intrusion Detection System (NNIDS) that support IPv4 protocol.

In this work, an identifying and recognizing person technique is presented based on its eye’s iris. The introduce technique utilizes several image processing methods; e.g. edge detection, contour following, chain coding, Gabor filters, image normalization, feature extraction, etc. JPEG images of size 256×256 pixels are converted into grayscale form by averaging their Red, Green and Blue bands.The produced grayscale image then traced into edges and boundaries using Marr-Hildreth edge technique with an appropriate Gaussian standard deviation value (i.e. σ =3).

There is a modern type of encryption called selective encryption which depends on the choice of some sensitive areas. The encryption of these areas leads to destroy the whole file.