Courts need to determine whether evidence is “safe” to put before a jury and will help provide a solid foundation for making a decision in the case. In practice, admissibility is a set of legal tests carried out by a judge to assess an item of evidence. This assessment process can become complicated, particularly when the evidence was not handled properly or has traits that make it less reliable or more prejudicial. Some jurisdictions have rules relating to admissibility that are formal and sometimes inflexible, while other jurisdictions give judges more discretion. In this case, both parties offered copies of ...
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INTRODUCTION In general terms, experts have a duty to present the objective, unbiased truth of the matter before the court. It is not their role to advocate for one side; that burden is on the attorneys. The UK Criminal Procedure Rules (CPR) specifically address this issue with the following statements: 1. An expert must help the court to achieve the overriding objective by giving objective, unbiased opinion on matters within his expertise. 2. This duty overrides any obligation to the person from whom he receives instructions or by whom he is paid. 3. This duty includes an obligation to inform ...
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1. Hardware as Contraband or Fruits of Crime. Contraband is a property that the private citizen is not permitted to possess. For example, under certain circumstances, it is illegal for an individual in the United States to possess hardware that is used to intercept electronic communications(18 USCS 2512). The concern is that such devices enable individuals to obtain confidential information, violate other people’s privacy, and commit a wide range of other crimes using intercepted data. Cloned cellular phones and the equipment that is used to clone them are other examples of hardware as contraband. The fruits of crime include property ...
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Investigating a computer intrusion requires one approach, while investigating a homicide with related digital evidence requires a completely different procedure. The specific role that a computer plays in a crime also determines how it can be used as evidence. When a computer contains only a few pieces of digital evidence, investigators might not be authorized to collect the entire computer. However, when a computer is the key piece of evidence in an investigation and contains a large amount of digital evidence, it is often necessary to collect the entire computer and its contents. Additionally, when a computer plays a significant ...
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New terms such as cybercrime and digital forensics have been created to address developments in criminal activities involving computers and in legislation and investigative technologies to address them. Such general terms can mean different things to different people and, to avoid confusion, it is important to understand their nuances. COMPUTER CRIME Because any crime can involve computers, it is not clear where to draw the line between crimes committed using computers and crimes simply involving computers. Although there is no agreed upon definition of computer crime, the meaning of the term has become more specific over time. Computer crime mainly ...
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Tries to reduce wastage of energy from all sources of energy inefficiency Collision – by using RTS and CTS Overhearing – by switching the radio off when transmission is not meant for that node Control Overhead – by message passing Idle listening – by periodic listen and sleep PERIODIC LISTEN AND SLEEP Each node goes into periodic sleep mode during which it switches the radio off and sets a timer to awake later When the timer expires, it wakes up Selection of sleep and listen duration is based on the application scenarios Neighboring nodes are synchronized together Nodes become active ...
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Types of network: Switched communication network Users are interconnected by means of some transmission lines, multiplexers and switches Eg: Telephone and SONET network (circuit switching) Eg: X.25,Frame relay,ATM(packet switching) Broadcast network A single transmission media is shared by all the users and information is broadcasted by an user into the medium. Examples: Multi-taped Bus Ring networks sharing medium Satellite communication using sharing of uplink and downlink frequency bands Packet radio network Wireless communication stations sharing a frequency band Broadcast networks require a protocol to orchestrate the transmission from the users. ISSUES IN MAC The question is “who goes next”? The protocols ...
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A local area network (LAN) is a communications system that allows the interconnection and sharing of resources between independent devices within a moderately sized geographic area. Distributed data interface networks Ethernet networks Token-ring networks Wireless networks Ethernet networks Ethernet is one type of local area network (LAN) topology that the i5/OS™ operating system supports. i5/OS Ethernet provides support for the Digital Equipment Corporation, Intel Corporation, and Xerox standard (Ethernet Version 2) and the IEEE 802.3 standard. Types of Ethernet Network: Half-duplex Ethernet Full-duplex Ethernet Fast Ethernet Half-Duplex Ethernet Generally, multiple stations in an Ethernet network show a single data path. ...
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Operate at the Data Link Layer Increase network performance Virtual circuits between source and destination Micro segmentation Multiple virtual circuits are called “switched bandwidth” Between two computers using a switch, two collision domains are created each with dedicated bandwidth Between two hubs using a switch, two collision domains are created each with shared bandwidth Filter based on MAC addresses Build tables in memory ADVANTAGES Increase available network bandwidth Reduced workload Increase network performance Smaller collision domains DISADVANTAGES More expensive than hubs and bridges Difficult to trace network connectivity problems through a switch Does not filter broadcast traffic
TRANSPARENT BRIDGES Also called learning bridges Build a table of MAC addresses as frames arrive Ethernet networks use transparent bridges Token Ring networks use source-routing bridges ADVANTAGES Extend physical network Reduce network traffic with minor segmentation Creates separate collision domains Reduce collisions Connect different architecture DISADVANTAGES Slower than repeaters due to filtering Do not filter broadcasts More expensive than repeaters