ANOMALY DETECTION PADA INTRUSION DETECTION SYSTEM (IDS) MENGGUNAKAN METODE CLUSTERING ANOMALY DETECTION ON INTRUSION DETECTION SYSTEM (IDS) BY CLUSTERING METHOD

ABSTRAKSI: Intrusion Detection System (IDS) adalah sekumpulan teknik dan metode untuk mendeteksi aktivitas-aktivitas yang terjadi pada level network dan host. Pada sistem ini terdapat dua pendekatan yang dilakukan : signature-based intrusion detection systems dan anomaly detection system. Pendekatan yang pertama memiliki kelemahan yang cukup rentan, yaitu pendeteksian hanya akan dilakukan terhadap data yang sudah didefinisikan. Sementara untuk anomaly detection, selain menggunakan data yang sudah didefinisikan, dapat pula dilakukan dengan menganalisis pola-pola anomali dari paket network yang datang, namun jika salah mengambil parameter maka metode ini justru akan sering mengakibatkan false alarm.Untuk menganalisis anomaly detection pada paket yang datang dapat dilakukan dengan menggunakan outlier detection scheme. Dengan metode ini, paket-paket yang datang akan dianalisis dengan menggunakan beberapa algoritma, diantaranya adalah clustering. Algoritma clustering pada metode outlier detection scheme melakukan analisis dengan cara meng-cluster-kan data dan menandai cluster terkecil, kemudian cluster terkecil tersebut akan dianggap sebagai anomali.Dalam Tugas Akhir ini dibangun suatu implementasi pendeteksian intrusion (serangan) terhadap sistem atau jaringan komputer menggunakan metode anomaly detection dengan algoritma cluster-based outlier detection. Proses clustering itu sendiri dilakukan terhadap data koneksi jaringan. Adapun implementasi dilakukan dengan menggunakan bahasa pemrograman HTML, script PHP dan DBMS MySQL.Pengujian terhadap sistem anomaly detection ini menunjukkan hasil akhir bahwa hasil pendeteksian anomali sangat bergantung pada tiga hal hal, yaitu tergantung pada pemilihan data yang digunakan untuk dianalisis (dataset), jarak maksimal yang diijinkan dari titik pusat cluster atau center ke setiap data yang menjadi anggota dari cluster tersebut atau biasa disebut jari jari cluster, dan perbandingan jumlah data instrusion dengan data normal pada dataset.Kata Kunci : Intrusion Detection System(IDS), clustering, anomaly detection, outlier detection scheme.ABSTRACT: Intrusion Detection System (IDS) is a group of techniques and methods for detecting activities that hapenned in network and host level. IDS has two approaches : signature-based intrusion detection system and anomaly detection system. First approach has any weakness, the detection can only done if the intrusion had been definited. Therefore except using the data which had been definited, we can also analyze anomaly patterns from the packets , but if we take the wrong parameter this method could eventually be a false alarm.Analyze anomaly detection in network data packets can be handled by outlier detection scheme method. With this method we can build the analysis with some algorithms, one of the algorithms is clustering. Clustering algorithm clustered the data and mark the smallest cluster with assumption that smallest cluster as an anomaly.This final Project will build an implementation of intrusion detection system in computer or network system using anomaly detection method with cluster-based outlier detection algorithm. The process is to clustering data connection record. Implementation use HTML programming language, PHP script, and MySQL DBMS.Anomaly detection system evaluation shows that the results are depend on three things, data which have been analyzed or data set given and the maximum distance betwen center to each data point that included in that cluster, or cluster radius values and ratio between normal data and instrusion data.Keyword: Intrusion Detection System(IDS), clustering, anomaly detection, outlier detection scheme

Cyclotron enhancement of tunneling

A state of an electron in a quantum wire or a thin film becomes metastable, when a static electric field is applied perpendicular to the wire direction or the film surface. The state decays via tunneling through the created potential barrier. An additionally applied magnetic field, perpendicular to the electric field, can increase the tunneling decay rate for many orders of magnitude. This happens, when the state in the wire or the film has a velocity perpendicular to the magnetic field. According to the cyclotron effect, the velocity rotates under the barrier and becomes more aligned with the direction of tunneling. This mechanism can be called cyclotron enhancement of tunneling

Dissipative Van der Waals interaction between a small particle and a metal surface

We use a general theory of the fluctuating electromagnetic field to calculate the friction force acting on a small neutral particle, e.g., a physisorbed molecule, or a nanoscale object with arbitrary dispersive and absorptive dielectric properties, moving near a metal surface. We consider the dependence of the electromagnetic friction on the temperature $T$, the separation $d$, and discuss the role of screening, non-local and retardation effects. We find that for high resistivity materials, the dissipative van der Waals interaction can be an important mechanism of vibrational energy relaxation of physisorbed molecules, and friction for microscopic solids. Several controversial topics related to electromagnetic dissipative shear stress is considered. The problem of local heating of the surface by an STM tip is also briefly commented on.Comment: 11 pages, No figure

Cosmological Production of Vector Bosons and Cosmic Microwave Background Radiation

The intensive cosmological creation of vector W, Z- bosons in the cosmological model with the relative units is considered. Field theoretical models are studied, which predict that the CMB radiation and the baryon matter in the universe can be products of decay and annihilation processes of these primordial bosons.Comment: 31 pages, 1 figur

Optical conductivity of a granular metal at not very low temperatures

We study the finite-temperature optical conductivity, sigma(omega,T), of a granular metal using a simple model consisting of a array of spherical metallic grains. It is necessary to include quantum tunneling and Coulomb blockade effects to obtain the correct temperature dependence of sigma(omega, T), and to consider polarization oscillations to obtain the correct frequency dependence. We have therefore generalized the Ambegaokar-Eckern-Schoen (AES) model for granular metals to obtain an effective field theory incorporating the polarization fluctuations of the individual metallic grains. In contrast to the DC conductivity, which is determined by inter-grain charge transfer and obeys an Arrhenius law at low temperature, the AC conductivity is dominated by a resonance peak for intra-grain polarization oscillations, which has a power-law tail at low frequencies. More importantly, although the resonance frequency agrees with the classical prediction, the resonance width depends on intergrain quantum tunneling and Coulomb blockade parameters, in addition to the classical Drude relaxation within the grain. This additional damping is due to inelastic cotunneling of polarization fluctuations to neighbouring grains and it qualitatively differs from the DC conductivity in its temperature dependence quite unlike the expectation from Drude theory.Comment: Added figures, published version, 16 pages, REVTe

Multidimensional cosmological models: cosmological and astrophysical implications and constraints

We investigate four-dimensional effective theories which are obtained by dimensional reduction of multidimensional cosmological models with factorizable geometry and consider the interaction between conformal excitations of the internal space (geometrical moduli excitations) and Abelian gauge fields. It is assumed that the internal space background can be stabilized by minima of an effective potential. The conformal excitations over such a background have the form of massive scalar fields (gravitational excitons) propagating in the external spacetime. We discuss cosmological and astrophysical implications of the interaction between gravexcitons and four-dimensional photons as well as constraints arising on multidimensional models of the type considered in our paper. In particular, we show that due to the experimental bounds on the variation of the fine structure constant, gravexcitons should decay before nucleosynthesis starts. For a successful nucleosynthesis the masses of the decaying gravexcitons should be m>10^4 GeV. Furthermore, we discuss the possible contribution of gravexcitons to UHECR. It is shown that, at energies of about 10^{20}eV, the decay length of gravexcitons with masses m>10^4 GeV is very small, but that for m <10^2 GeV it becomes much larger than the Greisen-Zatsepin-Kuzmin cut-off distance. Finally, we investigate the possibility for gravexciton-photon oscillations in strong magnetic fields of astrophysical objects. The corresponding estimates indicate that even the high magnetic field strengths of magnetars are not sufficient for an efficient and copious production of gravexcitons.Comment: 16 pages, LaTeX2e, minor changes, improved references, to appear in PR

Calculation of PandP_ and T_ odd effects in $"" sup 205_TIF including electron correlation

A method and codes for two-step correlation calculation of heavy-atom molecules have been developed, employing the generalized relativistic effective core potential and relativistic coupled cluster (RCC) methods at the first step, followed by nonvariational one-center restoration of proper four-component spinors in the heavy cores. Electron correlation is included for the first time in an ab initio calculation of the interaction of the permanent P,T-odd proton electric dipole moment with the internal electromagnetic field in a molecule. The calculation is performed for the ground state of TlF at the experimental equilibrium, R_e=2.0844 A, and at R=2.1 A, with spin-orbit and correlation effects included by RCC. Calculated results with single cluster amplitudes only are in good agreement (3% and 1%) with recent Dirac-Hartree-Fock (DHF) values of the magnetic parameter M; the larger differences occurring between present and DHF volume parameter (X) values, as well as between the two DHF calculations, are explained. Inclusion of electron correlation by GRECP/RCC with single and double excitations has a major effect on the P,T-odd parameters, decreasing M by 17% and X by 22%.Comment: 5 pages, REVTeX4 style Accepted for publication in Phys.Rev.Letter

Underbarrier nucleation kinetics in a metastable quantum liquid near the spinodal

We develop a theory in order to describe the effect of relaxation in a condensed medium upon the quantum decay of a metastable liquid near the spinodal at low temperatures. We find that both the regime and the rate of quantum nucleation strongly depend on the relaxation time and its temperature behavior. The quantum nucleation rate slows down with the decrease of the relaxation time. We also discuss the low temperature experiments on cavitation in normal $^3$He and superfluid $^4$He at negative pressures. It is the sharp distinctions in the high frequency sound mode and in the temperature behavior of the relaxation time that make the quantum cavitation kinetics in $^3$He and $^4$He completely different in kind.Comment: 10 pages, 2 figure

Avalanche Photo-Detection for High Data Rate Applications

Avalanche photo detection is commonly used in applications which require single photon sensitivity. We examine the limits of using avalanche photo diodes (APD) for characterising photon statistics at high data rates. To identify the regime of linear APD operation we employ a ps-pulsed diode laser with variable repetition rates between 0.5MHz and 80MHz. We modify the mean optical power of the coherent pulses by applying different levels of well-calibrated attenuation. The linearity at high repetition rates is limited by the APD dead time and a non-linear response arises at higher photon-numbers due to multiphoton events. Assuming Poissonian input light statistics we ascertain the effective mean photon-number of the incident light with high accuracy. Time multiplexed detectors (TMD) allow to accomplish photon- number resolution by photon chopping. This detection setup extends the linear response function to higher photon-numbers and statistical methods may be used to compensate for non-linearity. We investigated this effect, compare it to the single APD case and show the validity of the convolution treatment in the TMD data analysis.Comment: 16 pages, 5 figure