In the strictest sense; the term “mainframe computer” is generally regarded as meaning those computers that are compatible with the IBM System/360 series first introduced in 1965. Other very high-end computers that are not compatible with the IBM System/360 series are usually referred to as “servers”.

Now however; the term “mainframe computer” is typically used to refer to that group of high-end self-contained computers which incorporate copious numbers of built in “hot swap” capable redundant systems to provide added robustness as standard fare, as opposed to less well endowed server class computer systems.

The latter group includes collectives of grouped and associated computers known as server farms that may provide additional resilience through duplicated systems but on the whole do not provide the critical total internal system component redundancy of the mainframe computer.

If one feature or aspect of a mainframe computer was selected to be its defining characteristic then it would undoubtedly be reliable uptime. The vast majority of mainframe computers have provided continual service measured in years and in many instances decades of non-stop functionality.

Redundant Engineering

The major engineering feature of the modern mainframe computer that delivers this degree of reliable service is their considerable amount of redundant internal engineering. This is what gives mainframe computers their high reliability, tight security, extensive input/output facilities, strict backwards compatibility for older software, and high utilization rates (very little processing idle time) to support their characteristic massive throughput capabilities.

Hardware Servicing and Upgrades

In order for a mainframe computer to operate non-stop (run) for many years without interruption all repairs and hardware upgrades can and do take place during the normal operation of the mainframe computer. Once again this is another benefit that the inclusion of internal redundant hardware engineering makes possible.

Performance

Supercomputers; such as those at NASA's Columbia Advanced Computing Facility have their performance measured in terms of the number of floating point operations per second (flops) of which it is capable.

The standard yardstick by which the computational performance of a mainframe computer is measured and subsequently compared with itself at other times or against other mainframes is the number of sustained Millions of Instructions Per Second (MIPS) that it is capable of. As with supercomputers and flops performance the SI prefix system (Mega, Giga, and Peta etc) is also used when stating a mainframes MIPS performance to make these numbers more “human friendly”.

The smallest System z9 IBM mainframes today run at about 26 MIPS while the largest IBM System z10 mainframes can perform approximately 30,657 MIPS (or 30.6 Kilomips).

To give some idea of real world experience, a single mainframe may execute the equivalent of 10 to 100 or even more distributed processors' worth of business activity, however this is highly dependent on the workload. Merely counting processors to compare server platforms is extremely inaccurate.

Multiple Concurrent Operating Systems

Another aspect of the mainframe computer platform that I will only briefly touch on here is their ability to run or host not just one operating system at a time, but many. In this way a single mainframe computer can replace tens or even hundreds of smaller servers. In so doing administrative and management costs are greatly reduced yet at the same time still providing for superior scalability and reliability.

Processing Tasks

Mainframe computer processing has always tended to focus on problems which are limited by input/output and reliability ("throughput computing") as well as solving multiple business problems concurrently (mixed workload). In marked contrast to the supercomputer; which uses massive parallel processing to work on a single highly complex task, the mainframe computer generally makes use of its parallel processing capacity to simultaneously run multiple different less complex concurrent tasks.

Times haven't changed much as the types of tasks that mainframe computers usually perform today still revolve around the so called “mission critical” operations that require much repetitive or parallel processing such as correlation of data collected during a census or a survey, statistical processing and analysis, financial transaction processing (banks) and Enterprise Resource Planning (ERP).

Mainframe Computer Design and Performance Optimization

One of the major critical factors in mainframe processing performance is due to the very nature of the types of tasks that it performs because these tend to involve considerable use of external data sources (input).

Thus; in order to optimize performance, mainframes are built with designs that incorporate numerous ancillary “service” processors whose job it is to supply the main processing core processors with a regulated, steady and persistent stream of data to process and then to service the subsequent output requirements of the main processing core processors processing.

Some of these service processor tasks include cryptographic support, I/O handling, monitoring, notifications, logging, authentication and memory handling. The result is that the total processor count of a mainframe is much higher than would otherwise be obvious from many purely MIPS-based benchmarking measurements as the MIPS-based measurement generally does not include those instructions executed by the ancillary “service” processors just the overall machines productive throughput/output.

One side-effect of this is that adding processors to a mainframe computer will speed up the entire machine's performance over its entire workload transparently.

Fuzzy Marketing

In recent times there has been some blurring of the term "mainframe," with some PC and server vendors referring to their systems as "mainframes" or "mainframe-like." This is somewhat misleading as it is widely recognized by the larger players in the mainframe computer industry and academia alike that mainframe computers constitute a class of computer genuinely demonstrably different from all other classes of computational platforms.

Mainframe Pricing

Historically mainframes have earned a reputation for being rather expensive but this is no longer the case. It is now possible to buy and configure a complete IBM mainframe system (with software, storage, and support), under standard commercial use terms, for about $50,000 (U.S.). The price of z/OS starts at about $1,500 (U.S.) per year, including 24x7 telephone and Web support while z10 BC systems start at around $100,000 US.

In addition; many vendors including HP Unisys, HP, Groupe Bull, Fujitsu, Hitachi, and NEC now primarily use commodity Intel CPUs rather than custom processors. This has dramatically reduced their development costs and many have also cut back on their commitment to mainframe software developed for similar reasons some time back and the current economic climate will only add further pressure to continue this trend for sometime into the near future.

Combined these factors all point to a competitive if somewhat stagnant development climate for the mainframe computer with the only real impetus being supplied by IBM who has its own large research and development organization designing their own new, homegrown CPUs; including mainframe processors. IBM is currently expanding its software business; including its mainframe software portfolio.

The company takes the view that with a dramatic reduction in effective competition from its rivals it's open season for them with regards to mainframes. From a future perspective I guess IBM believes that things will improve and when they do they will be in such a dominant position they will not have anything to fear from any potential competition no matter what form it takes.

Conclusion

Above all else it is their reliability that defines and identifies the mainframe class of computer platform with uninterrupted service histories measured in many numbers of years. Many of the current IBM mainframe computers have been working non-stop for over a decade now. Not bad value for the dollar.

"To Break is not to build", it is necessary to hear it very often as the argument that “Cracking” this rough employment not demanding a superior intelligence. Well, let's understand. The in itself statement "to Break - not to build" challenges nobody. But whether it is lawful is used with reference to "Cracking"? In the pledged saying a word to break has a direct sense "to Damage, put out of commission, to destroy." But after all, when speak to break the program, do not mean its damage, infringement of its working capacity, and have in view of only change of its behaviour in more convenient party. That is, when speak "to break the program" mean its improvement; it is literally "to make the program more convenient, practical and functional".

Imagine an entrance door in your apartment. How it is possible to get to your apartment?

1. You open a door - free programs.

2. You furnish the clue to other person - the licence program.

3. The bear-hunter comes and opens locks on your door - a crack.

4. Here comes the healthy guy with an axe (if the door is made from steel with a disk saw) and starts to cut to pieces your door, so it after that and is not similar to a door is just and there is that case when the saying "is pertinent to break - not to build" for actually, to make a new door, according to certain parameters, it is much more difficult, than to break out it! "Crackers" do not go "with axes", they are similar to bear-hunters whom so competent that can open the lock without a key, nearly without having spoilt it thus! That there was no this false interpretation of a word to "break", to use a word better to "crack", "breaking" - it more corresponds to true value put in a phrase "to break the program". So, speaking "to crack the program" you speak more correctly and any more do not push others on wrong associations. That who is still assured what to crack the program easier, than to "fasten" to it protection, it is recommended to try to make this easy business (a lot of  CrackMe`s  literally "crack me") waits for you:) ). Everyone skilled "Cracker" perfectly knows that it is possible to crack the same program very much with a considerable quantity of the ways, many of them essentially different, some of them are more rational, others less. It is necessary to understand well programming as a whole to have chances of breaking of not trivial protection. That in language of high level occupies one line, in disassembler can occupy not one page of machine commands. You tried to understand sometime another's source codes in which there are no comments (or they on a foreign language which you do not know)? This employment demands a lot of time. At the same time "Cracker" still has a huge heap of any restrictions and reefs which cannot be at a writing of programs in languages of high level. Freedom in many respects but to crack more or less difficult protection, it is necessary to have many knowledge, experience and patience. Search of optimum decisions, research alternative ways, a writing of the auxiliary programs, all it opens broad lands for creativity.

So “Cracking” is an art!

Part 1. A lawful Crack

The description: Speculations, about the one who is guilty and who is not.

Date: 04.06.2008 (though almost all has been written in the morning 30.10.2007)

Introduction

(It is possible not to read, it basically for people far from a crack)

Abbreviations: the software producer (further it is simple "the Author", and itself "Program") and creator of the crack (further is simple "the Author of a crack"). As a crack we will understand the program or the certain information/instruction allowing (after its application) to use the Program without registration/purchase (without the permission of its author) or to activate certain functions or on the contrary their disconnecting.

For example, a classical situation: the Program - some exe-file created by the Author, the Crack - a patch (the Program program-modifier) created by the Author of a crack.

So, the Author declares that has lost profit of that the Author of a crack has created the program, capable to update the Program so that its usage without limitations is possible....

Main:

Probably, each of us has on kitchen a knife. Yes... If somebody kills someone this knife we after all will not accuse of it factory on production of kitchen knifes, the truth?! Other example: Fire-arms if someone has shot someone it does not mean at all that in it the manufacturer of this weapon is guilty! To all of us known, the popularity and reliability, Kalashnikov's automatic machine become real can a cause of death, but it looking how to tell, the inventor (M.Kalashnikov) has told "kills not the automatic machine, and the person" ... It is difficult to disagree. So, that you have created the automatic machine, have made a knife or store it for yourself is yet a crime! And here their usage! With violation of the present legislation, it already a crime! Therefore and the Author of a crack it is impossible to accuse of its manufacture as that, and, especially, it is impossible to accuse anybody that they store its (Crack) for themselves! And the one who uses it is guilty only (applies)! Means it is impossible to accuse the Author of a crack of any consequences of application of its crack, whether it is the missed benefit or still that - it as Kalashnikov, only has invented!

We go further. Someone attentive will ask: stop! But how the Author of a crack has created it?” The possible answer: "It decompiled the Program, has studied its operation (in full or in parts it not important) and has thought up as it is possible to change, that that did not do something or on the contrary". Yes, here, in most cases, output is obvious the Author of a crack is guilty (has broken the Program License agreement). But it can somehow in another way has come to the solution (has dawned, it is casual, etc.) then it is not guilty.

So, the Author of a crack can be accused only of HOW he has created the crack, i.e. whether it used any illegal methods and resources at crack creation.

Someone will ask then "And what for he has created then a crack? Here the kitchen knife is created, those vegetables, for example, to cut..."

Hmm... Yes, really what for? Give, again we will return to our example with the weapon. What for to the person the weapon or what for it invent and make? And you heard about gifted weapon? Yes heard... What for it? For murder? Probably, to show "Look what I abrupt!" Or "I am not afraid of you - can not show off!" Or "respect my rights!", and generally is the power or Independence/freedom (who whom that is any more an essence it is important). So, for example, for the author of a crack is can be: "I consider that everyone has the right to be independent of the Author ON", for this purpose, who stores is can to be, for example: "I can be independent of the Author ON".

Freedom to us is guaranteed by the Constitution, dear friends (P.2 Constitution of the Russian Federation)! Moreover "the Recognition, observance and protection of the rights and freedom of the person and the citizen - a state duty." (Item 2 of Constitution of the Russian Federation).

Yes... As the choice in our life is important, to tell choice possibility, and what there variants it another story altogether more precisely...:)

Freedom... It is important for everyone!

So those who really have broken it let appear at the Law, (killed, has pressed a trigger hook, has applied a crack...), instead of those who creates and invents!

To be continued...

How to Draw a Circle

As a mathematical description, circle is a combination of points with the same length from a fixed point. To draw a circle, two things we need. They are the coordinate of center of the circle and radius or diameter of it. Let's now draw our first circle by Solidworks. Let's draw a circle with a center of origin and a radius of 20 mm.

1. Click the sketch button to define a plane on which you will draw. Since our drawing is 2D, any plane can be chosen. I choose top plane as a reference plane.
2. Click the circle button on the toolbar and choose origin as the center point of the circle. Afterthat, drag the circle to the out of the page.
3. By clicking "smart dimension" button , dimension the radius of circle. Since the radius is 20 mm, specify diameter as 40 mm.

How to Draw Filleted Arcs

To draw filleted arcs, we first need a corner of two intersecting lines. As an example, we will filet one corner of 40x40 mm square. Lets first draw the square by using rectangular button on the toolbar.

1. Click the fillet button on the toolbar.
2. Enter the radius of fillet as 5 mm into the fillet parameters space.
3. Choose the corner point which you want to fillet. Be careful here, you should select the point not the sides you want to fillet. After that, Solidworks automatically dimension the filleted arc. Here is the result.

Since I have been familiar with Key Creator for 2 years, I have drawn many simple and complicated geometries. However, one of my friends claimed that I couldn't draw the solid form of an oblique cone. I stumped when I heard his challenge on my technical drawing capability. It was really difficult to solve such problem but I did. Now, listen and learn how to draw an oblique cone. There may be of course many ways of drawing an oblique cone but I claim that mine is the easiest.

Oblique cone is a cone whose apex are not aligned above the center of the base. First of all we'll determine the exact location of the point of apex. After that, we draw the base circle with its given dimensions. Most of the time we know the radius or the exact location of the center. Then we use the menu of solid drawings. Under create menu we see an option swept. Now push the swept and then loft button. We choose curve-edge option for circle and point option for the point from sub-menu. Then, Key creator applies your command automatically. Look. You draw an oblique cone. The final part is to make a layout for your solid drawing. To do this, press into layout button and choose create instance option. Now you can see the top, front, right and isometric views of your work on the screen. How simple how easy.

I wish life could be as easy as drawing an object.