Table of contents.

1. Great Britain

     1.1.1 Introduction…………………………………………………. 3

     1.1.2 Wales………………………………………………………... 3

   1.1.3 England…………………………………………………….. 3

   1.1.4 Chester………………………………………………………. 4 

    1.1.5 Scotland ……………………………………………… 4

  1.2.1 The UK on the world tourist`s map....................................... 4

           Accommodation

    1.2.1 Hotels and Guest Houses…………………………………..4-5

   1.2.2 Renting and Buying……………………………………….. 5

    1.2.3 Leisure and Holiday Parks ………………………………... 5

2. Problems in microelectronic circuit technology................6-9

3. Digital signal processor………………………………………… 9

       3.1 Typical characteristics ………………………………….. 9

      3.2 A simple digital processing system ………………………….  9

      3.3 Architecture ………………………………………………. .9-10

      3.4 History …………………………………………………..10-11

      3.5 Modern DSPs …………………………………………………11

4. Diverse Hacker Attack Methods ……………………………... 12

     4.1 Social Engineering …………………………………………. 12

     4.2 The Virtual Probe ………………………………………..12-13

    4.3 Social Spying ……………………………………………..13-14

    4.4 Sniffing ……………………………………………………….14

    4.5 How Does a Sniffer Work ?.............................................14-15

     4.6 How Hackers Use Sniffers ……………………………….15-16

       4.7 How to Detect a Sniffer ……………………………………..16

5. References …………………………………………………. 17 
 
 
 

Great Britain

Introduction

   The UK is a land made up of many regions, each with a special character and cultural heritage. There are non-stop cities; festivals of music, theatre, literature and the arts; and regional countryside with rolling hills, dramatic cliffs, ancient forests, rugged mountains and tranquil lakes. There are also wonderful islands to visit including the extraordinary range of the Scottish Islands, the Isle of Man, Anglesey, the Scilly Isles, the Isle of Wight and the Channel Islands. They have different traditional cultures, delightful scenery and offer many habitats for wildlife.

   The British Isles is visited by millions of people each year, many returning time and again. It is seeped in history and has some stunning landscapes. It is also quirky at times, so you are assured of an interesting visit!

   Wales

   The principality of Wales is full of fascinating places to visit and stay. The castles of Beaumaris, Conwy, Harlech and Caernarfon are officially listed as World heritage sites and provide an insight into the troubled past of this great land. The national park of Snowdonia is stunning and provides walkers and climbers with ample opportunities to challenge their limits. South Wales also has interesting places to visit: Pembrokeshire is especially inviting for tourists.

   England

   We all know about the attractions of London but England has a lot more to offer outside of the city. The ‘English Riviera’, Torquay, is blessed with good weather and is a major tourist attraction. This is a great place to stay and explore the local seaside resorts and go inland towards the vast moors.  
Windsor castle is a great place to visit and the town and surrounding areas are beautiful. Warwick castle in the centre of England is world famous and holds regular evens to show how life was like in the time it was built.  
 

   Chester

   This Roman town has a fascinated history stretching back over 1500 years. This can be seen from the Roman, Medieval and Tudor remains liberally scattered across the city. The Walls surrounding the city can be walked around in a couple of hours and allow plenty of opportunity to take photographs. The world famous Rows date back over 500 years and are great for walking and shopping.

   Scotland

   A great place to visit, Scotland still has many places that are relatively uninhabited. And are great for getting away from it all. Ben Nevis is the highest mountain in the British Isles and the numerous lochs provide great fishing (Beware of the Loch Ness monster!) . In parts you can still hear Gaelic spoken and we all know about the Scottish expertise in making Whisky! You can also visit the ski resorts of Aviemore in the Cairngorms . Glasgow, the capital is now recognised as a centre of culture as well as being a great shopping centre.

             The UK on the world tourist`s map

   Accommodation

   Hotels and Guest Houses

   You will find a significant difference in both price and facilities between hotels and guest houses in the UK. Hotels usually offer breakfasts, lunches, teas, dinners, a licensed bar and a range of services and facilities to suit individuals, families and often business groups. Country house hotels will often add recreational facilities in their grounds such as golf, tennis, swimming, health spas, gyms and attended play areas for children. Top league international hotels in London and major cities offer comprehensive amenities and services for business and holiday guests, and a choice of first class and luxury accommodation. Guest houses may not have bars or offer lunch or teas, but will have television and sitting lounges.

   Hotels have between one and five stars; guest accommodation between one and five diamonds. In Scotland and Northern Ireland all tourist accommodation is also graded regularly to provide a clear indication of the level of facilities you can expect.

   Renting and Buying

   If you are planning a longer stay in the UK, you may consider renting or buying property in the UK.

   Rented property is available all over the UK and there is a large rental market for properties in London. Rented property is offered both furnished and unfurnished and typically involves short-lease tenancies. National, regional and local estate agents also represent owners of rented property and you can also find apartments ('flats') and houses available to let through online agencies, newspaper advertisements and dedicated property magazines.

   Estate agents often provide a complete service for those wishing to buy property. This typically includes professional services such as valuing and surveying potential properties. They may also offer in-house or affiliated legal services to cover the buying process (known as 'conveyancing') and often have links to established mortgage firms who provide long-term loans for purchases.

   Leisure and Holiday Parks

   Leisure and holiday parks are a way of enjoying an extremely wide variety of recreational and leisure pursuits at one site. They are located all over the UK with many based at or near coastal resorts. They usually offer accommodation for touring or camping as well as lodges, chalets or spacious static caravans for hire - all well equipped so you can set up your temporary home as you wish.

   The great benefit of this form of holiday accommodation is the facilities for young children which can include kids clubs, attended play areas, activity workshops, waterslides, heated indoor and outdoor swimming pools, children's farms, pets corners and even summertime pantomimes. For teenagers and adults there are nightclubs, pubs, restaurants and a variety of sports. Some leisure parks focus on particular interest holidays such as sailing, golfing, fishing or horse-riding.  

   PROBLEMS IN MICROELECTRONIC CIRCUIT TECHNOLOGY

    The manufacture of silicon microcircuits consists of a number of carefully controlled processes, all of which have to be performed to well-defined specifications.

   In order to understand how transistors and other circuit elements can be made from silicon, it is necessary to consider the physical nature of semiconductor materials.

   In a conductor current is known to be carried by electrons that are free to flow through the lattice of the substance.

   In an insulator all the electrons are tightly bound to atoms or molecules and hence none are available to serve as a carrier of electric charge.

   The situation in a semiconductor is intermediate between the two: free charge carriers are not ordinarily present, but they can be generated with a modest expenditure of energy.

   Semiconductors are similar to insulators in that they have their lower bands completely filled. The semiconductor will conduct if more than a certain voltage is applied. It should be noted that a crystal of pure silicon is a poor conductor of electricity. Thus, conductivity poses a problem.

   Several other requirements are imposed on materials. The basic demand appears to be conductivity because it can substantially improve the resistance and delay times for VLSI. The improvement of conductivity has been made in several ways. Most semiconductor devices are known to be made by introducing controlled numbers of impurity atoms into a crystal, the process called doping.

    To improve the semi-conductor crystal the impurities known as dopants are added to the silicon to produce a special type of conductivity, characterized by either positive (p-type) charge carriers or negative (n-type) ones. In the furnace the crystals are surrounded by vapour containing atoms of the desired dopant. These atoms enter the crystal by substituting for the semiconductor atoms at regular sites in the crystal lattice and move into the interior of the crystal by jumping from one site to an adjacent vacancy. Suppose silicon is doped with boron. Each atom inserted in the silicon lattice creates a deficiency of one electron, a state that is   called a hole. A hole also remains associated with an impurity atom under ordinary circumstances but can become mobile in;   response to an applied voltage. The hole is not a real particle, of course, but merely the absence of an electron at a position;   where one would be found in a pure lattice of silicon atoms. Nevertheless the hole has a positive electric charge and can carry electric current. The hole moves through the lattice in much the same way that the bubble moves through a liquid medium. An adjacent atom transfers an electron to the impurity atom, 'filling" the hole there but creating a new one in its own cloud of electrons; the process is then repeated, so that the hole is passed   along from atom to atom.

   To define the microscopic regions that are exposed to diffusion in various stages of the process, extremely precise photolithographic procedures have been developed. The surface, of the silicon dioxide is coated with a photosensitive organic compound that polymerizes wherever it is struck by ultraviolet radiation and that can be dissolved and washed away everywhere else. By the use of a high-resolution photographic mask I he desired configurations can thus be transferred to the coaled water. In areas where the mask prevents the ultraviolet radiation limn reaching the organic coating the coating is removed. An elemental acid can then attack the silicon dioxide layer and leave the deriving silicon exposed to diffusion.

   A transistor can be made by adding a third doped region in a diode so that, for example, a p-type region is said to be sandwiched between two n-type regions. One of then-doped areas is called the emitter and the other, the collector; the p-region between them is the base.

   The transistor described is called npn transistor. There may be pnp transistors.

   The first transistor structures were formed by alloying or diffusion in bulk single-crystal Ge or Si, but with the development of "planar technology" in the early 1960s the possibility of forming high frequency transistors and integrated circuits using epitaxial semiconductor films was realized! 

   The recent years have seen considerable interest in the subject of oxygen and its precipitates in silicon. It has now been established that their presence can have a variety of effects, harmful as well as beneficial. Oxygen concentration is known to influence many silicon wafer properties, such as wafer strength, resistance to thermal warping, minority carrier lifetime, and instability in resistivity. Oxidation is widely used to create insulating areas. However many phenomena happen not to be understood at present.

   An important aspect of the oxidation process is its low cost. Several hundred wafers can be oxidized simultaneously in a single operation.

   Reactive gas plasma technology is reported to be presently in wide-spread use in the semiconductor industry. This technology is being applied to the deposition and removal of selected materials during the manufacture of semiconductor devices.

   Contributing greatly to the manufacturing technique is a unique crystal forming method known as epitaxial growth.

   After 1964 epitaxial growth remains an important technique in uniconductor device fabrication and the demand for improved device yield per slice, still higher device operating frequencies and more sophisticated device structures has needed continuing innovation and development

   Even before the invention of the transistor the electronic industry had studied the properties of thin film of metallic and insulating materials.

   The techniques for the deposition of thin films are numerous: evaporation, sputtering, anodization, radiation, induced "cracking" or polymerization, chemical reduction, thermal reduction of oxidation and electrophoresis. The first three are the major techniques used in integrated thin film circuit construction and are also applicable to silicon integrated circuitry and device work. These methods singly or in combination enable a variety of resistive, insulating and constructive materials to be laid down onto a suitable substrate.

   In the fabrication of a typical large-scale integrated circuit there are more thin-film steps than diffusion steps. Therefore thin-film technology is probably more critical to the overall yield and performance of the circuit than the diffusion and oxidation steps are. A thin film happens even to be employed to select the areas on a wafer that are to be oxidized. 

   Digital signal processor

   Typical characteristics

   Digital signal processing algorithms typically require a large number of mathematical operations to be performed quickly and repetitively on a set of data. Signals (perhaps from audio or video sensors) are constantly converted from analog to digital, manipulated digitally, and then converted again to analog form, as diagrammed below.

   A simple digital processing system

   Most general-purpose microprocessors and operating systems can execute DSP algorithms successfully, but are not suitable for use in portable devices such as mobile phones and PDAs because of power supply and space constraints. A specialized digital signal processor, however, will tend to provide a lower-cost solution, with better performance, lower latency, and no requirements for specialized cooling or large batteries.

   The architecture of a digital signal processor is optimized specifically for digital signal processing. Most also support some of the features as an applications processor or microcontroller, since signal processing is rarely the only task of a system. Some useful features for optimizing DSP algorithms are outlined below.

   Architecture

   One implication for software architecture is that hand optimized assembly is commonly packaged into libraries for re-use.

   Hardware features visible through DSP instruction sets commonly include:

   Hardware modulo addressing, allowing circular buffers to be implemented without having to constantly test for wrapping. A memory architecture designed for streaming data, using DMA extensively and expecting code to be written to know about cache hierarchies and the associated delays. Driving multiple arithmetic units may require memory architectures to support several accesses per instruction cycle. Separate program and data memories, and sometimes concurrent access on multiple data busses. Special SIMD operations.