Monthly Archives: May 2011

Wide Area Network (WAN)

Types and characteristics of WANs

What is a WAN?

There are two dominant definitions of a wide area network (WAN). The accounting definition of a WAN is a network that covers large geographic areas, usually for interconnecting multiple local area networks (LAN). The definition of a WAN is a network through a public network or a commercial airline, with a multiple WAN technologies

What are its main components?

The main components are WAN routers, switches and modems. These elements are described below in the hardware section.

CPE – devices in the customer premises are called customer premises equipment (CPE).
The customer owns or leases the CPE CPE service provider. A copper wire or optical fiber connects the CPE to the nearest central service provider or office. This bond is often called the local loop or “last mile”.

DTE / DCE – Devices that put data in the local loop are called circuit-terminating equipment or data communications equipment (DCE). Customer devices that pass data to the DCE are called data terminal equipment (DTE). The DCE primarily provides an interface to the DTE in the communication link to the WAN cloud.

Hardware

In a WAN, you need different types of hardware components to function. Typical elements of the equipment you need in a WAN are:

Router – An electronic device that connects a local area network (LAN) to a network (WAN) and handles the task of routing messages between the two networks. Operates at Layer 3, and makes decisions with IP addresses.

Switch – The switch is a network device that selects a path or circuit for sending a data unit to its next destination. Operates at Layer 2 and use MAC addresses to send the data to correct destination.

Best wireless router: 6 strategies on how to choose the best for your network

If you have multiple devices, such as desktop computers, laptop and printer and want to create a network, then you need a router. And to avoid having so many wires connected to these devices, especially from one room to another, you need a wireless router. So how do you choose the best device for your wireless router network?

1. First, the router has been selected to be compatible (working) with existing wireless cable or DSL modem, you can use. Many laptops are sometimes equipped with a wireless card that is integrated, but some, especially the elderly. All desktop computers have a wireless card, either. Therefore, you may need to buy one. If you have an Apple Mac desktop or notebook, it is likely that the wireless card is integrated. And any other device to be shared on the network, a printer must be compatible, too.

2. To avoid security problems, even with the best wireless router device on the market, the password protection is recommended. Also, password protection repels pests from accessing your wireless connection, because you can not tell how far the signal reaches.

3. Some routers come with more than one antenna that allows them to be pointing in different directions, therefore, the wide area of ??coverage is another important factor when choosing a network router. For example, the coverage will include one or two rooms, high or low?

Getting wireless devices and cell phones for free

You can fly, but I do not recommend it. You can also get a hand to me from a relative or friend, but of course this is not new. Why would anyone give you a free cell phone anyway? It is likely to be higher, and its new features and technology of yesterday. What about online surveys? You know, the one in a million to take surveys, and spam your friends to do the same thing for free? If you get many Christmas and birthday cards each year, this could be the way to solve this problem.

Where I can find free cell phones

Many mobile operators offer these deals when you sign up for a package of wireless calls and the conclusion of an agreement or contract that usually lasts one to two years. A better place to look is a center for wireless management, of which only three dealers in the United States. These include Amazon, Wirefly and Let.

Reason, a treatment center is often better than going directly through a wireless service provider as an authorized dealer will be more devices to choose a provider of wireless services in a store front in bulk. Even if a company can offer some nice mobile devices and provides its main interest is to sell a calling plan, not a phone. On the other hand the main objective of a store is selling a calling plan, and will seduce you with a great deal on a new cell phone. They usually have a wider selection of mobile phones and devices, and lower prices for a service provider.

Android devices wireless access to Internet and mobile broadband

Android devices like the Motorola Milestone 854 and an HTC Desire 6275, using the Android software stack which was bought by Google, which then made open source to be used by any developer working on software for mobile devices. Android is based on the Linux kernel, and can be used to develop mobile applications that fully utilize the true potential of a mobile phone, and allows developers to combine the various functions of a phone is capable of providing.

The use of Android, database applications on your phone can be combined with third-party applications to provide services not otherwise be possible, for example by combining data on the Internet with your cell phone, which would not be possible without Android. You can design your phone to match your interests and make full use of mobile broadband applications and wireless Internet. In other words, an Android developer can allow you to use your phone to impossible without it.

Because it is an open source software, anyone can use, and is currently installed on a number of Android devices, including smartphones sold by Acer, cherry, HTC, LG, Motorola, Samsung and Sony Ericsson, and some shelves and electronic readers. Once installed, you can make full use of the Android Market, which offers a range of applications such as the time from Mobile, offering the latest issue of Time magazine and Sports Tap, also free, providing the latest sports scores and statistics.

ADSL modems

Users wishing to connect to ADSL broadband use the ADSL modem to do so. ADSL modems are a cost effective solution for users and are popular all over the world including the United States. The ADSL modem enables the transfer of data over the Internet directly to your computer. The types of data provided by ADSL modems are compatible with U.S. and European digital hierarchies. Users can buy in the market ranges modem speed and diverse capabilities. The minimum system allows data rates of 1.5 or 2.0 Mbps download a 16 kbps duplex channel. Other configurations offer 6.1 Mbps speed with a 64 kbps duplex. You can also choose products with rates of 8 Mbps and duplex rates of 640 kbps.

There are three types of ADSL modems. They are the Ethernet ADSL modem, ADSL modem PCI, USB and ADSL modem. Ethernet ADSL modem can be entered directly into an Ethernet port on the PC or is used to add a modem to secure broadband routers. PCI ADSL modem fits inside the computer. USB ADSL modems are the most popular of all ADSL modems, and are designed to connect personal computers to ADSL.

Now, how an ADSL modem? The ADSL modem organizes the flow of global data blocks. This data is created by multiplexing downstream channels, duplex channels, and maintenance of the canal. During data transmission, ADSL modem gives an error correction code for each block. ADSL modems are capable of accommodating ATM transport with variable rates and severance costs of ATM and IP protocols.