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Action Games- The Thrill Is Addictive

March 10th, 2010

When you watch live action on movie screens, you get excited. Combined with sound effects the action can be a real thrill. Some actions that we watch takes the breath away. How about Action games on computers?

Some of the makers of action games make great animations and may include a story line. Stories always attract us. Tell a story and everybody will listen. The action games on computers use this very well to produce games that can take your breath away thinking of the imagination and artistry applied by the maker.

Adventures, space fights, planes colliding in mid air, think of any action and you will find it used in a game. Most of these games are free online. Action games give great thrill and despite called for teenagers they are for the family to enjoy them together. Action games test the response of the player and sharpen the judgment. Such games are not pure fun. They can help as training tools if used properly.
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Data Recovery and Your Computer

March 9th, 2010

Have you ever wondered if what you know about data recovery is accurate? Consider the following paragraphs and compare what you know to the latest info on data recovery.

Sooner or later your company could become the victim of a natural disaster, or something much more common like a lightning storm or downed power lines.

Just because your company may be a small business doesn’t mean it’s immune to data disasters. If a small business does not have a good and tested disaster recovery plan in place when disaster hits they may never fully recuperate and it may even cause them to go out of business. Sometimes even a data recovery service is unable to be of any help.

Following are some questions that should be answered in order to give you some idea of what you need to do to that will help you if you do have a data disaster situation.

Do you know where your company’s most important data files are located?

Are these files being backed up and by what means?

How often do you run these data backups and are they verified and tested?

Do you have automated controls that correctly and on a consistent basis do the backups?

Do your data backup tapes go off-site and how often?

Do you have some kind of security against tampering or theft of your data backups?

Do you keep your servers, routers, hubs, and phone system controllers in locked areas to keep them more secure?

Does just anyone have access to your servers and your other technology assets or do you limit access to at least two, but no more than four people?
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Cisco CCNA / CCNP Certification: OSPF E2 vs. E1 Routes

March 5th, 2010

OSPF is a major topic on both the CCNA and CCNP exams, and it’s also the topic that requires the most attention to detail. Where dynamic routing protocols such as RIP and IGRP have only one router type, a look at a Cisco routing table shows several different OSPF route types.
R1#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
In this tutorial, we’ll take a look at the difference between two of these route types, E1 and E2.
Route redistribution is the process of taking routes learned via one routing protocol and injecting those routes into another routing domain. (Static and connected routes can also be redistributed.) When a router running OSPF takes routes learned by another routing protocol and makes them available to the other OSPF-enabled routers it’s communicating with, that router becomes an Autonomous System Border Router (ASBR).
Let’s work with an example where R1 is running both OSPF and RIP. R4 is in the same OSPF domain as R1, and we want R4 to learn the routes that R1 is learning via RIP. This means we have to perform route redistribution on the ASBR. The routes that are being redistributed from RIP into OSPF will appear as E2 routes on R4:
R4#show ip route ospf

O E2 5.1.1.1 [110/20] via 172.34.34.3, 00:33:21, Ethernet0

6.0.0.0/32 is subnetted, 1 subnets

O E2 6.1.1.1 [110/20] via 172.34.34.3, 00:33:21, Ethernet0

172.12.0.0/16 is variably subnetted, 2 subnets, 2 masks

O E2 172.12.21.0/30 [110/20] via 172.34.34.3, 00:33:32,
Ethernet0

O E2 7.1.1.1 [110/20] via 172.34.34.3, 00:33:21, Ethernet0

15.0.0.0/24 is subnetted, 1 subnets

O E2 15.1.1.0 [110/20] via 172.34.34.3, 00:33:32, Ethernet0
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Author: admin Categories: Computer Tags: , , , , , , , , , , , , , , ,

Antenna - How One Works

March 4th, 2010

It’s probably not something many people are interested in unless they’re some kind of an electrical engineer or just bored, but understanding how an antenna works can be useful when the one on your TV or radio goes south on you and the reason is beyond your comprehension.

Trying to explain how an antenna works in simple English is not an easy task as there are a lot of technical specifications that need to be explained. But a general understanding is possible without getting into tech speak that would make Einstein cringe.

In order for an antenna to work it has to radiate. Your antenna, whether TV or radio has what is called free electrons running through it. It is these free electrons that vibrate. The question becomes, how do these free electrons vibrate and what causes them to vibrate?

Well, in real life it takes an electric field to move an electron. If you take an isolated straight dipole, the power comes from the combined fields of all the charged particles, both positive and negative, in the antenna. We’ll call this field the antenna’s coulomb field.

In addition to this field, the antenna exhibits a magnetic field that is the sum of the magnetic fields of all the free moving electrons. The antenna also has a dynamic electric field that is the vector sum of the dynamic electric fields of all the free electrons. What we can do is separate the electric field of the antenna at any point in space into two components. One of the components will be in phase with the total magnetic field and the other will be 90 degrees out of phase. The in-phase component is the radiation field of the antenna and the out of phase component is the induction field. At the antenna, both fields are parallel to the metal surface.

What happens is that the coulomb field and the induction field fall off much more quickly than the radiation field as the distance increases from the antenna. When you reach distances greater than a few wavelengths from the antenna, you have what is called the antenna’s far field. This field is pure radiation. As you get closer to the antenna you have what is called the antenna’s near field. This field is a mixture of radiation, coulomb, and induction fields. Still with us? Great, we’re getting to the good part.
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Author: admin Categories: Communications Tags: