Wireless networks use radio waves instead of wires to transmit data between computers. Here’s how:

The Binary Code: 1s and 0s

It’s well known that computers transmit information digitally, using binary code: ones and zeros. This translates well to radio waves, since those 1s and 0s can be represented by different kinds of beeps. These beeps are so fast that they’re outside the hearing range of humans.

Morse Code: Dots And Dashes

It works like Morse code, which is a way to transmit the alphabet over radio waves using dots (short beeps) and dashes (long beeps). Morse code was used manually for years via telegraph to get information from 1 place to another very quickly. More importantly for this example, though, it is a binary system, just as a computer system is.

Wireless networking, then, can be thought of as a Morse code for computers. You plug in a combined radio receiver and transmitter, and the computer is able to send out its equivalent of dots and dashes (bits, in computer-speak) to get your data from here to there.

Wavelengths And Frequencies

You might wonder how the computer can send and receive data at high speed without becoming garbled nonsense. The key to wireless networking is how it gets around this problem.
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Buyer Beware – Ignorance can be a financial waste and a lot of hassals. Before you buy any wireless equipment, you need to be sure about what you’re doing. There’s nothing worse than having everything there and finding that it doesn’t work in your house, or with your computers, or over the distances you need. Here’s a handy checklist of the things that you really ought to do before you go out and spend any of your hard-earned cash on wireless networking equipment.

Interference Checks

While it won’t stop a wireless network from working altogether, interference in its frequency range can slow it down significantly, as well as reducing its range. If something is causing interference, the first thing you’ll know about it is when your connection stops working — unless you know what to look for.

There are two very common causes of wireless interference: wireless phones and microwave ovens. 2.4Ghz, the most common wireless networking frequency, is also a commonly-used wireless phone frequency. It is possible, though, to find phones that use other frequencies. Microwave ovens, on the other hand, operate at around 2.4Ghz by definition. It should be alright to have devices like these in your house, but certainly not in the same room as any computer that you plan to use a wireless connection with.
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Home security is an important issue for any person. A person’s home is their castle and they want to feel safe and secure. There are several security measures that can be implemented to ensure security such as alarms but one that ensures peace of mind is a wireless home security camera package.

What’s need in the package is a camera to fit either just outside the front or back door that transmits a wireless signal. The best one to buy would be one that has night vision to ensure you can see everything at night. The second would be a receiver. Some receivers have screens so you can watch what’s going on no matter where you are and others need to be connected to a computer or television to see the transmission.

If connected to a computer or television the live feed from the camera can be directly recorded to a hard drive or a cassette or DVD depending on which is convenient. Several cameras can be implemented to get several signals meaning more coverage of the home and the surrounding area.

These wireless home security packages are common and can be purchased at most electronics stores. They are on the expensive side but are worth the purchase for the kind of technology it has. With almost everything becoming wireless these days it was only a matter of time until cameras became wireless also.
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It is a hierarchical representation of all the objects and their attributes available on the network. It enables administrators to manage the network resources, i.e., computers, users, printers, shared folders, etc., in an easy way. The logical structure represented by Active Directory consists of forests, trees, domains, organizational units, and individual objects. This structure is completely independent from the physical structure of the network, and allows administrators to manage domains according to the organizational needs without bothering about the physical network structure.

Following is the description of all logical components of the Active Directory structure:

Forest: A forest is the outermost boundary of an Active Directory structure. It is a group of multiple domain trees that share a common schema but do not form a contiguous namespace. It is created when the first Active Directory-based computer is installed on a network. There is at least one forest on a network. The first domain in a forest is called a root domain. It controls the schema and domain naming for the entire forest. It can be separately removed from the forest. Administrators can create multiple forests and then create trust relationships between specific domains in those forests, depending upon the organizational needs.

Trees: A hierarchical structure of multiple domains organized in the Active Directory forest is referred to as a tree. It consists of a root domain and several child domains. The first domain created in a tree becomes the root domain. Any domain added to the root domain becomes its child, and the root domain becomes its parent. The parent-child hierarchy continues until the terminal node is reached. All domains in a tree share a common schema, which is defined at the forest level. Depending upon the organizational needs, multiple domain trees can be included in a forest.

Domains: A domain is the basic organizational structure of a Windows Server 2003 networking model. It logically organizes the resources on a network and defines a security boundary in Active Directory. The directory may contain more than one domain, and each domain follows its own security policy and trust relationships with other domains. Almost all the organizations having a large network use domain type of networking model to enhance network security and enable administrators to efficiently manage the entire network.

Objects: Active Directory stores all network resources in the form of objects in a hierarchical structure of containers and subcontainers, thereby making them easily accessible and manageable. Each object class consists of several attributes. Whenever a new object is created for a particular class, it automatically inherits all attributes from its member class. Although the Windows Server 2003 Active Directory defines its default set of objects, administrators can modify it according to the organizational needs.

Organizational Unit (OU): It is the least abstract component of the Windows Server 2003 Active Directory. It works as a container into which resources of a domain can be placed. Its logical structure is similar to an organization’s functional structure. It allows creating administrative boundaries in a domain by delegating separate administrative tasks to the administrators on the domain. Administrators can create multiple Organizational Units in the network. They can also create nesting of OUs, which means that other OUs can be created within an OU.
In a large complex network, the Active Directory service provides a single point of management for the administrators by placing all the network resources at a single place. It allows administrators to effectively delegate administrative tasks as well as facilitate fast searching of network resources. It is easily scalable, i.e., administrators can add a large number of resources to it without having additional administrative burden. It is accomplished by partitioning the directory database, distributing it across other domains, and establishing trust relationships, thereby providing users with benefits of decentralization, and at the same time, maintaining the centralized administration.

The physical network infrastructure of Active Directory is far too simple as compared to its logical structure. The physical components are domain controllers and sites.

Domain Controller: A Windows 2003 server on which Active Directory services are installed and run is called a domain controller. A domain controller locally resolves queries for information about objects in its domain. A domain can have multiple domain controllers. Each domain controller in a domain follows the multimaster model by having a complete replica of the domain’s directory partition. In this model, every domain controller holds a master copy of its directory partition. Administrators can use any of the domain controllers to modify the Active Directory database. The changes performed by the administrators are automatically replicated to other domain controllers in the domain.
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You must have seen them. Web addresses like http://tinyurl.com/2gj2z3 which, when you click on them, take you to another web page. Why use them? Are there any risks in using them?

URL stands for Uniform Resource Locator. It’s the posh technical term for a web address. Web addresses normally take the form http://www.somesite.com/somepage.html, which is not too much of a problem. But some site names can get very long, and so can page names. The increased use of database-driven sites mean that URLs can get very long indeed, and most of them is computer gobbledygook. They are impossible to type in, if you are reading them in a print article, and often get corrupted by word-wrapping when they appear in an email or blog posting.

An URL shortener is a web service that takes a long address that’s hard to type, and turns it into a short one. You should use them in articles for print publication, classified ads, emails, blog and forum postings, anywhere there is a danger that the full address may be corrupted, or that someone may need to type the address into a browser manually.

But there is a danger in using short URLs that may make people afraid to use them. The short address disguises the real destination. This makes it easy for somebody to post an innocent looking message encouraging people to click on a link that takes them to a site which infects their computer with spyware, or something equally undesirable.
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Navino launched its search engine gateway service recently. For most of the Internet surfers, search engine gateway is a pretty new concept compared with meta search engine or multi search engine. Put it in simple, it is a web service, which can let you search the best information from the best content providers in one website.

When we try to find information everyday, most of us might go to Google.com. Yes, it’s true. Most of the time, Google works well. But does Google return the best information? I guess you would agree that the search engine’s ranking algorithm could only give a good answer, but not the best. Well, you may ask, where can I get the BEST? The best weather information? The best book information? The best price for your favorite mp3 player? The short answer is from the brain, from the hand picked information. Therefore, Navino’s editors and their users give out that the best weather website is weather.com, the best book website is amazon.com and the best price information is froogle.

Besides best hand picked information resources, Navino also provide the search engine gateway technology. Using this technology, you can search all the best website at Navino. All you need to do is to add a unique search name before your searching keywords.
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