Posts Tagged ‘VoIP’
In this fast track modern life, we are always in the need of solutions that can connect us with others at cheaper costs. In this context, it can be said that VoIP has emerged a real solution for people who are always on a move. As a matter of fact, the IP telephony services and solutions are just perfect for frequent travelers and business users. People have started to accept VoIP as a single solution to a myriad of requirements pertaining to communication.
The VoIP Phone Service is based on a very innovative concept. It is a convergence of technologies that enables users to communicate with others at significantly lower rates. Users can make the most of their broadband connections to make cheaper telephone calls anywhere in the world. So, with this new technology long distance as well as international calls can be made at cheaper rates.
As of now, the situation is such that the VoIP phone service is on the verge of replacing traditional landlines, if not fully, then to a significant extent. There is an ease and convenience of talking over the internet with a broadband phone service. It works on the principle that voice signals are converted to digital signals that travel over the internet. An adapter is used to convert a regular phone to a device that can be used to make calls routed over the internet. This technology works well if you have a high speed internet connection, a microphone and an adapter that converts normal voice signals to their digital versions.
This service is turning to be appropriate for frequent travelers and busy professionals. They can make the most of VoIP internet phone service and make internet phone calls from many areas of the globe, sometimes absolutely free. A person could be based in London, for instance and could be subscribing to the services of a VoIP phone service provider there. VoIP services come with the provision that in instances when he is traveling to other destinations, his calls would be treated as local calls. So, this is a big plus point especially for business travelers, who can now save a lot of money in connecting with people.
It is also beneficial to use the Voice over IP phone service as home phone, incase people are making long distance calls frequently. This saves a lot of your money. Moreover, it is very functional as many call centers and networks come to your aid. Then there are other advantages such as three way calling, call waiting, caller ID and call forwarding. These facilities are not available on a traditional landline.
The emerging IEEE 802.16 standard, commonly known as WiMAX, promises to deliver last mile wireless broadband internet access capable of carrying data intensive applications, such as VoIP and streaming video, to Metropolitan Area Networks, as well as sub-urban and rural communities. WiMAX is considered a disruptive technology, designed as an alternative to fixed line DSL and coaxial technologies, and with its 802.16e revision, the cell phone networks as well.
Worldwide Interoperability for Microwave AXcess will operate over licensed and non licensed frequencies using non line of sight (NLOS) and line of sight technologies, extending broadband coverage to cities and towns wirelessly via a metro area network. Additionaly, because of its far reaching capabilities and ease of implementation, wimax is the one technology likey to bridge the Digital Divide, connecting underdeveloped regions and sparsely populated rural areas much more cost effectively than deploying a wireline infrastructure.
WiMAX and WiFi Compared
The widespread adoption of the wireless LAN in the business community, as well as the emergence of WiFi hotspots in public areas, airports, hotels and cafes, has been of tremendous significance in providing mobility to business people and consumers alike. Thanks to the open standards guided by the 802.11 committee and the WiFi Alliance, WiFi technology is becoming ingrained in our society. WiMAX plans to take WiFi a step further.
While the two technologies may sound the same, they are from their conception designed for totally different applications. WiFi is a short range standard that was designed primarily as an extension of the local area network (LAN) to provide mobility for the end user. It operates over unlicensed frequencies and has a range of about 100 meters, depending on obstructions. Typically one access point will be connected to a fixed line network, either a wired LAN or a DSL/cable broadband connection, and the range can be extended by adding more access points at appropriate distances.
WiMAX, on the other hand, is designed to function as a carrier network, or a wireless Internet service provider (WISP), blanketing whole cities and regions with broadband Internet access comparable to DSL. Coverage in optimal conditions could reach 50 kilometers, but in reality are more like 5 km for users with NLOS customer premise equipment (CPE), or up to 15 km with a CPE connected to an external line of sight antenna.
As the older more established technology, the 802.11 WiFi has been used in a mesh topology to cover larger areas such as college campuses and municipalities, for example to connect the terminals in police vehicles to their database. The emerging 802.16 WiMAX will be better suited for larger deployments, and will in fact compliment the private WiFi networks by offering a cheaper and more secure Internet access for data and voice applications.
The WiMAX Standards: Fixed, Nomadic, and Mobile
The 802.16 standard developed by the IEEE envisions a fixed wireless broadband network operating in the spectrum range of 10 GHz to 66 GHz. Originally, only the licensed spectrum was addressed in this range, and line-of-sight multipath technology was dealt with by adopting OFDM as the standard. Subsequent revisions added the 2 GHz to 11 GHz band to the spectrum, and incorporated support for non-line-of-sight technologies and Quality of Service (QoS) techniques, a prerequisite for such time sensitive applications as voice and video.
The revision known as 802.16-2004(d) rolled up all the previous revisions and then added some. Most of these original issues dealt with the Physical and Media Access Control layers, and resulted in a standards list of optional and mandatory elements by which vendors could design their products.
The resulting fixed WiMAX standard has a data rate of up to 40 Mbps, support for half and full duplex transmission, improved QoS, and the incorporation of multiple polling techniques, ultimately reducing packet collisions and overhead.
Base stations are to support several different topologies, such as wireline backhauling, microwave point to point connections, and the ability for the WiMAX base station to backhaul itself by reserving a part of the bandwidth for that purpose.
By design, 802.16d would cater to the residential and small business markets offering wireless broadband access with speeds comparable to DSL. Enterprise markets could be served at T1/E1 data rates.
While this version of WiMax is called fixed, it is in all actuality nomadic. Users on a private WiFi network indoors could be passed off seamlessly to the publicWiMAX network when moving outdoors, their hardware determining the best network available. Devices on the WiMAX data network would include laptops, PDAs, and smart phones equipped with an on board WiMAX capable chip or PC card, utilizing the spectrum for voice, data, video, and music transfers.
Nomadic WiMAX provides for limited mobility in that the range of coverage is handled by the same base station.
WiMAX Goes Mobile
With the adoption of the 802.16e revision in late 2005, all the hype has been on Mobile WiMAX, a technology designed to compete with the cellular networks.
With major support from manufacturers like Intel, Motorola, Siemens, and Nokia among others, mobile WiMAX is built on open standards and is purported to be 4 times faster than the cellular 3G technologies (EVDO, HSDPA). Significant cost savings can be achieved for voice applications by placing calls over the Internet through VoIP.
802.16e provides for fast and seamless handoffs between base stations, with a cell radius of about 3 miles, similar to cellular networks. The standard was ratified in late 2005, and real world applications are beginning to show up in 2007, with more robust development expected throughout 2008.
Because this technology is such a threat to the legacy telecommunications industry, it is no surprise that Sprint Nextel will be deploying WiMAX as opposed to EVDO in its 4G network. Sprint has been buying up much of the WiMAX spectrum, and has recently announced a partnership with Nokia to deploy WiMAX to four Texas cities by mid 2008. This is not their first WiMAX network, and telcos around the globe have been doing the same.
The 802.16 standards are a work in progress, and as such, are subject to changes and revisions. As the standards committee works on the technology, the WiMAX Forum hopes to do what the WiFi Alliance did for the 802.11 standards, by promoting interoperability between components through testing, and offering WiMAX certification to vendors that conform to the 802.16 standards.
It should be noted that many of the WiMAX implementations at the time of this writing are proprietary, and thus do not necessarily follow the recommendations of the IEEE or the WiMAX Forum. The broadband wireless ISP Clearwire Communications has over 200,000 subscribers in 375 cites, and calls its service a WiMAX-class solution, utilizing next-generation, non-line-of-sight wireless technology. Other early adopters of pre-WiMAX technology are forging ahead, providing wireless broadband access to residential consumers and the small business market, with many companies climbing aboard the evolving standards bandwagon to assure interoperability and backwards compatibility of devices and applications.
VoIP (Voice over Internet Protocol) is fast becoming a preferred method of communication in the home. It allows broadband users to make telephone calls over the internet.
The attraction of VoIP is not hard to fathom: it offers the potential to make ultra-cheap or even free calls anywhere in the world, to use local telephone number codes even if you are not physically based in that location and even to take or make calls without the need to keep your computer switched on.
So how does it work? Basically, VoIP converts voice signals from your telephone into a digital signal that travels over the internet, then converts it back at the other end, therefore allowing you to speak to anyone with a regular phone number, as well as other broadband users.
VoIP is still at its developmental stage, but the number of VoIP providers is increasing, giving you more choice and better calling plans. VoIP services are available for both commercial and residential users, ranging from services that operate PC-to-PC through to a handset plugged into your router-to-phone. Many broadband providers now offer a VoIP service in their bundled deals.
As long as you have broadband VoIP can be used in several ways, from using software on your computer to integrate with your microphone, to VoIP phones that look like regular phones.
Due to calls being made over a broadband connection, VoIP calls are significantly cheaper than your regular phone calls, especially international calls. The other advantage of VoIP calls is that as long as there is an internet connection you can make phone calls. Even if you’re getting your broadband via mobile broadband without plugging into a wall socket you can still make calls.
The major disadvantage of VoIP is call quality; many users with slow broadband connections suffer from a variety of problems that makes it hard to hear what someone is saying. Another major disadvantage is that a VoIP line can never be a true replacement for a normal phone line because it’s not possible to call emergency services, and if you try to make calls to countries that have an analogue phone service it won’t work.
However, with broadband technology improving and millions being invested in wireless technology and networking, even mobile phones are vastly improving their internet capabilities and some manufacturers looking at allowing VoIP calls straight from your mobile perhaps one day we won’t need our phone lines anymore.
If you are interested in taking advantage of current broadband internet technology then you should compare many cheap broadband providers available in your area.