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Scope of the system: The system frames certain rules based upon the input given by the user. It
then allows traffic inwards or outwards based upon the rules. The system also detects certain
well-known attacks and gives warnings to the user.
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What is the function of forensic response tool kit?
A type of Intrusion Detection & Prevention tool
Best leak detection test is when refrigeration system is?
A vacuum
What are the three types of intruders?
1. IntroductionThe problem of intruders in computer networks is rather old. In fact, it has been persistentsince the beginning of the computer age. One of the first official documents concerningcomputer security and intruders is from 1980. It is the so called Anderson report [Ande1980].Its contents point out how current the threat of intruders was even back then. The Andersonreport [Ande1980] defines a lot of intrusion scenarios that are still up-to-date and applicable,which is one of the reasons that it is still referred to today. On this account, section 2 of thisarticle explains the different types of intruders and their characteristics.The following section presents several intrusion detection techniques and how intrusions canbe prevented. A promising approach for intrusion detection is introduced and its mode ofoperation is briefly depicted. Considering an example of the effectiveness of this approach wewill show how the intrusion detection of this tool works in practice.Whereas section 3 deals with closing security gaps by means of intrusion detection, section 4brings out security issues regarding the password management on UNIX, and it describesgeneral problems of the password selection. Good passwords need to be distinguished frombad passwords in order to make it a more difficult task for attackers to guess passwords. Wewill present some of the techniques that claim to be solutions to these problems and discusstheir effectiveness.2. Threat scenariosThe term "intruders" compromises more than just human attackers who manage to gain accessto computer resources although the resource was not meant to be used by them in the firstplace. Apart from these human attackers who are popularly called "hackers", intruders can becomputer programs that seem to be useful, but contain secret functionality to invade a systemor a resource. These programs are also known as Trojan horses. Programs containing virusescan act as intruders too. Computer systems can be any kind of internal network, e.g. within acompany. Computer resources can be work stations, mobile computers, as well as computerprograms. Although we don't need to distinguish between human attackers and computerprograms that perform illicit actions, we need to know some characteristics that defineintruders. One has to keep in mind that the following definitions not only apply to humanbeings, but to illicit computer programs too, although below we will talk about "individuals"acting in different types of threat scenarios. This is done in accordance with most of theliterature about this subject.In general, three types of intruders can be distinguished: the misfeasor, the masquerader, andthe clandestine user. The definition for these terms can be traced back to [Ande1980] whichestablishes these terms in detail. To refrain from repeating an exhaustive list of definitionsonly the important differences in the characteristics of misfeasor, clandestine user, andmasquerader will be addressed.- 2 -MisfeasorImagine someone who emails blueprints and schematics the company he works for is holdinga patent on to his home email account in order to sell it to a competitor company. Anotherexample of such a misfeasance of ones privileges is printing offensive material at work.Nowadays we can take for granted that someone has access to an email accounts or a printerat work. It is obvious that no data was accessed without authorization in both of theseexamples. However, the user misused some of his privileges.On this account we define misfeasor as an individual who works within the scope of hisprivileges but misuses them.Clandestine userAnother user might take advantage of a security hole in the operating system in order to gainadministrative privileges to a computer resource. How this can be achieved on a recentoperating system will be shown in section 3.3 and we define clandestine user as an individualwho seizes supervisory control to disengage or avoid security mechanisms of the system suchas audit and access controls.MasqueraderA third individual could steal another user's login id and the associated password. If this datais at the disposal of an attacker he can use the system incognito for his illicit intensions. Yet,sometimes stealing ids and passwords is not even necessary, because some users mightchoose very simple passwords, which can be a mere repetition of the login id, some easilyaccessible information related to their personal life, such as their spouse's name, or apassword that is very short, for example only 4 characters or even shorter.We define masquerader as an individual who overcomes a systems access control to exploit alegitimate user's account.Common to misfeasor, clandestine user, and masquerader is that either they aim to increasethe amount of their privileges or they use the system in an unforeseen way.If a system is tricked by an attacker to provide users with privileges they did not hold before,the system is in a compromised state.It has to be noted that misfeasors end clandestine users are internal attackers. That means,initially they are legitimate users having some privileges in the internal network, whereas themasquerader can be an attacker from outside the networks if he happens to correctly guess apassword.3. Identifying IntrudersTypically, everyone stores plenty of sensitive data in ones user account, such as personal data,address books, data one is required to carefully protect by law, and data that grants access toother systems or that is supposed to prove one's identity for example. It is fairly easy to findexamples for each of these types of data:Personal data could be emails from your spouse. Address books might contain phone numbersand addresses of the suppliers the company does business with. Time tracking of engineershas to be handled with great care. Furthermore, if one has stored passwords or private andpublic keys on ones account, the security systems that try to grant secure access to othersystems or that try to prove one's identity by these means will be useless. Moreover, if suchsensible data can be accessed by others the owner runs a high risk of financial losses andpersonal harm.- 3 -3.1. Intrusion detectionThe threats of attackers have to be addressed to. To this end intrusion detection techniqueshave been developed to close security gaps of operating systems and network access controls.Below different types of intrusion detection techniques will be introduced briefly and anoverview of their weaknesses and strengths will be given as they appear in [Stal2003] and[Ilgu1995].Threshold DetectionThreshold Detection is one of the most rudimentary intrusion detection techniques comparedto the other ones. The idea of this approach is to record each occurrence of a suspicious eventand to compare it to a threshold number. However, it turns out that establishing thresholdnumbers as well as rating the security relevance of events is a rather difficult task which isoften based on experiences and intuition. An implementation of this approach was developedat Los Alamos National Laboratory and it is called NADIR.Anomaly DetectionAnomaly Detection is one of the earliest approaches which try to meet requirements describedin [Ande1980] to distinguish masquerader, misfeasor, and clandestine user. Implementationsof this approach are realized in statistical or rule based forms. Typically, anomaly detectionrequires little knowledge of the actual system beforehand. In fact, usage patterns areestablished automatically by means of neural networks for example. Intrusion detectionsystems that have already implemented this approach are IDES, Wisdom & Sense, and TIM.Rule-based Penetration IdentificationRule-based Penetration Identification systems are expert systems that recognize single eventsas well as sequences of events. The foundation pillar of this approach is a suspicious recordfor each user. Initially this record has the value zero and the more suspicious a user becomes,the higher his suspicious record. Examples that implement this technique are IDES, NADIR,and Wisdom and Sense.Model-based Intrusion DetectionA higher level of abstraction than the approaches above is characteristic of this intrusiondetection technique. The objective of Model-based Intrusion Detection is to build penetrationscenarios of network rather than characterizing the behavior of a specific user. For identifyingpenetrations the pieces of evidence are evaluated against a hypothesis.Intrusion preventionThe goal of Intrusion prevention is to close well known security gaps. A well known systemusing this approach is COPS (Common Oracle and Password Security System)Table 1 detects which intrusion detection technique is suitable to identify a certain typeattacker.Misfeasor Clandestine user MasqueraderThreshold detection No Yes YesAnomaly Detection No Yes YesRule-based Penetration identification Yes Yes NoModel-based Intrusion detection Yes Yes NoIntrusion Prevention No Yes NoTable 1 - Suitability for detecting attackersIn short, statistical-based techniques try to determine whether or not the current behaviormatches patterns seen earlier, whereas rule-based approaches define proper behavior. For thisreason statistical-based techniques are better in detecting masqueraders, whereas rule-based- 4 -ones are better in detecting misfeasors and clandestine users. In order to define all types ofintruders, systems for intrusion detection use more than just one approach to grant security.
What does RADAR stand for acronymically?
R.A.D.A.R. is the acronym of RAdio Detection And Ranging. Radar is a system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain. By using innovations such as the Doppler shift of reflected waves, various properties can be determined about the relative motion of aerial and ground phenomena.
What is the difference between scope and objectives?
scope is why to do and objective is how to do
What is a system intrusion detection system?
There is nothing.
What is a Web based Intrusion Detection System?
There is nothing.
What is web based intrusion detection system?
There is nothing.
What intrusion detection system's efficiency decreases with encryption?
NIDS.
What is Instruction Detection System?
When you go to the bathroom. ^ Dont waste people's time. Do you mean Intrusion Detection System? If so, an Intrusion Detection System, or IDS for short, is a physical device, or a piece of software that monitors networks or systems for malicious activities.
What is a feature of an intrusion detection system?
Searches for features of known attacks
Jack's network intrusion detection system has alerted him to a buffer overflow attack against his web server. After further review of the alert log Jack realizes his intrusion detection system is det?
False Positives
Jack's network intrusion detection system has alerted him to a buffer overflow attack against his web server After further review of the alert log Jack realizes his intrusion detection system is det?
False Positives
Host intrusion detection systems or HIDS are used for what purpose?
Host intrusion detection software or devices are made to monitor your system or network activities for malicious or policy violations. Not all of them actually stop the intrusion, however.
What intrusion detection software is the most easily downloadable?
There are many intrusion detection software downloads available. My conclusion would be EXRAY Intrusion Detection. It is very easy to download and it is free.
What is systemic instruction?
When you go to the bathroom. ^ Dont waste people's time. Do you mean Intrusion Detection System? If so, an Intrusion Detection System, or IDS for short, is a physical device, or a piece of software that monitors networks or systems for malicious activities.
Computer-based devices that examine each packet they detect are called?
Usually clumped together as firewalls. Devices like them are IPS - Intrusion protection system. IDS - Intrusion detection system.
