Wi-Fi , Blue tooth, VOIP

Many of us have mobiles with Wi-Fi and Bluetooth...how many know what it is all about... just a simple review on these technologies..:



WiFi

Most agree that wireless networking represent the future of computer and Internet connectivity worldwide. Wi-Fi ("Wireless-Fidelity") continues to be the pre-eminent technology for building general-purpose wireless networks.

Wi-Fi is a brand originally licensed by the Wi-Fi Alliance to describe the underlying technology of wireless local area networks (WLAN) based on the IEEE 802.11 specifications.
It was developed to be used for mobile computing devices, such as laptops, in LANs, but is now increasingly used for more services, including Internet and VoIP phone access, gaming, and basic connectivity of consumer electronics such as televisions and DVD players, or digital cameras.

More standards are in development that will allow Wi-Fi to be used by cars in highways in support of an Intelligent Transportation System to increase safety, gather statistics, and enable mobile commerce (see IEEE 802.11p). Wi-Fi and the Wi-Fi CERTIFIED logo are registered trademarks of the Wi-Fi Alliance - the trade organization that tests and certifies equipment compliance with the 802.11x standards.


Bluetooth Wireless Technology

Bluetooth is a specification for using low-power radio technology to link phones and computers over short distances without wires. Learn about Bluetooth technology to network cell phones, PDAs, and computer peripherals.
The name "Bluetooth" is borrowed from Harald Bluetooth, a king in Denmark more than 1,000 years ago.
Bluetooth networks feature a dynamic topology called a piconet or PAN. Piconets contain a minimum of two and a maximum of eight Bluetooth peer devices.

Devices communicate using protocols that are part of the Bluetooth Specification. Definitions for multiple versions of the Bluetooth specification exist including versions 1.1, 1.2 and 2.0.

WiFi Vs Bluetooth:

Although the Bluetooth standard utilizes the same 2.4 Ghz range as 802.11b and 802.11g, Bluetooth technology is not a suitable Wi-Fi replacement.
Compared to Wi-Fi, Bluetooth networking is much slower, a bit more limited in range, and supports many fewer devices. As is true for Wi-Fi and other wireless technologies today, concerns with Bluetooth technology include security and interoperability with other networking standards. Bluetooth was ratified as IEEE 802.15.1.


VOIP

Voice over Internet Protocol, also called VoIP, Internet telephony, is the routing of voice conversations over the Internet or through any other IP-based network.

Companies providing VoIP service are commonly referred to as providers, and protocols which are used to carry voice signals over the IP network are commonly referred to as Voice over IP or VoIP protocols. They may be viewed as commercial realizations of the experimental Network Voice Protocol (1973) invented for the ARPANET providers. Some cost savings are due to utilizing a single network to carry voice and data, especially where users have existing underutilized network capacity that can carry VoIP at no additional cost. VoIP to VoIP phone calls are sometimes free, while VoIP to PSTN(Public swithced telephonic network) may have a cost that's borne by the VoIP user.

VoIP can facilitate tasks that may be more difficult to achieve using traditional networks:

* Incoming phone calls can be automatically routed to your VoIP phone, regardless of where you are connected to the network. Take your VoIP phone with you on a trip, and wherever you connect to the Internet, you can receive incoming calls.
* Free phone numbers for use with VoIP are available in the USA, UK and other countries from organizations such as VoIP User.
* Call center agents using VoIP phones can work from anywhere with a sufficiently fast and stable Internet connection.
* Many VoIP packages include PSTN features that most telcos (telecommunication companies) normally charge extra for, or may be unavailable from your local telco, such as 3-way calling, call forwarding, automatic redial, and caller ID.

[edit] Mobility

VoIP allows users to travel anywhere in the world and still make and receive phone calls:

* Subscribers of phone-line replacement services can make and receive local phone calls regardless of their location. For example, if a user has a New York City phone number and is traveling in Europe and someone calls the phone number, it will ring in Europe. Conversely, if a call is made from Europe to New York City, it will be treated as a local call. Of course, there must be a connection to the Internet e.g. WiFi to make all of this possible.
* Users of Instant Messenger based VoIP services can also travel anywhere in the world and make and receive phone calls.
* VoIP phones can integrate with other services available over the Internet, including video conversation, message or data file exchange in parallel with the conversation, audio conferencing, managing address books and passing information about whether others (e.g. friends or colleagues) are available online to interested parties.