The new networks are divided into two main technologies: WiMAX and Long TermEvolution (LTE). The two systems use similar approaches to supply the availability of bandwidth than the current one. A method called OFDM (Orthogonal frequency-division multiplexing) allows a base station to split a portion of spectrum in sub-channels. The signal strength of the subchannels and the number of channels allocated to different devices can be changed. OFDM allows highspeed data transmission, even far away from the base station, and fits well with all types of radio interference present in urban areas, where the signals reflected on the walls produce confusing echoes.

Both LTE and WiMax are based on the MIMO method (multiple input, multiple output). It uses multiple antennas to create a single wireless connection. MIMO can package the data with a higher density in the wireless spectrum available than a system with a single antenna, which consumes the same amount of energy.

WiMax has arrived on the market two years before LTE; it offers a theoretical maximum download speed of 144 megabits per second compared to the 360 ​​of LTE (the United States a standard residential broadband connection is around 10 megabits per second ). LTE seems to have an overwhelming speed advantage, but in reality wireless mobile companies are far from reaching that performance of both technologies. In the U.S., Sprint’s WiMax network reach speeds between 3 and 6 megabits per second, while Verizon’s LTE network is between 5 and 12 megabits per second.

Although Sprint and Verizon have them labeled as 4G, these services do not actually meet the performance criteria that the ITU (International Telecommunication Union) has called officially for 4G services. But the latest version of WiMax and LTE are trying to meet these standards, guaranteeing download speed up to 1,000 megabits per second or even higher.

Although WiMax has been developed more quickly (the first large-scale deployment dates back to 2008) most operators in the U.S., Europe and Japan are using LTE for next-generation wireless networks. The main reason is that they assume that LTE network is technically easier to integrate with their existing structures.

But some suppliers, such as T-Mobile in the United States to upgrade their existing 3G networks, they prefer a system called HSPA+. T-Mobile claims that HSPA+ enables peak download speeds of 21 megabits per second, enough to compete with next-generation networks, at least for now.

At present all the network operators are committed to enhancing the capacity and flexibility of their 3G networks. Over the next four years, when the next generation systems will be developed and 3G chips will become cheap enough to make their appearance in a wide range of consumer products, these systems will attract more subscribers of the LTE network.

The biggest obstacle to the improvement of these systems comes from the wired network, not from the wireless. The cell towers and base stations must be connected to the same network hub. These links from one point to another, which typically use copper telephone wires or special connections or microwave, in recent years have become real bottleneck, forcing operators to adopt the more expensive fiber connections.

About 95 percent of the new Verizon LTE data network will be over fiber. But dig into the streets to lay fiber optic cable in densely populated areas can be expensive. For this reason, AT&T is committed to improving its 3G service in New York, which must withstand the impact of thousands of iPhone users.

But, as it is very annoying to lose the Internet connection when we are working, the TL-MR3220 integrates the 3G/WAN failover function, which allows you to choose whether to give priority to the Wan(DSL) or 3G mobile connection. The router will automatically switch to wireless connection with secondary priority when the primary signal is weak.
Once the service is restored, router will back to the connection with higher priority, this will keep “always-on” Internet connection.

TP-Link presented also the Access Point TL-WA701ND that allows you to connect to the wireless network gaming consoles, printers,external hard drives, smartphones, iPad, iPhone. It integrates “repeater” function with WDS (Wireless Distribution Service , see how to extend coverage of wireless home network with WDS) technology that improves the strength of wi-fi network coverage in large environments. What makes the TL-WA701ND very simple in its setup is the Quick Secure Setup (QSS) function that allows you to establish a wireless connection protected by a password simply touching a button.

The IEEE organization is working to define a standard for vertical handover, the 802-21 between Wi-Fi, WiMax and 3G/4G. The horizontal handover is already used and is the transition from one cell to another within the same network (or between different networks using the same technology, such as in roaming).
Recently, efforts have multiplied between operators, academics and experts to reach a vertical handover efficiently managing to talk to different technologies. The reason is that there is an urgent need: in all developed countries the broadband mobile networks show signs of saturation. A remedy, already adopted in some countries (USA, Japan, United Kingdom) are the femtocell (small cellular base station, typically designed for use in a home) and picocell (wireless communication system typically covering a small area, such as in-building ) which installed by the user, are used to relieve the main operator (macrocell). In recent days, there was a historical overtaking in the United States: the number of femtocells has exceeded the number of the macrocell.

The weaknesses of this solution are the cost of the equipment and the need to have adequate backhaul (ie a fast connection to the rest of the network;now it happens through adsl-dsl). So it would be useful relieves traffic of mobile users on the wi-fi hot spot if they are present.The hot spots are in fact connected to a wired network, where bandwidth is less poor than mobile.

How it vertical handover works: software on the pc ’s user knows when there is a sufficient Wi-Fi signal, in that case it moves the connection on the network. Otherwise it uses the mobile network through UMTS/4G/3G air cards connected to a PC.
The challenge of the algorithm is to maintain a stable connection as the user moves from one network to another: this is the vertical handover. You do not realize they have switched from Wi-Fi to 3G or the opposite continuing to navigate normally. It can use any Wi-Fi hot spot that is authorized to have access. To succeed they had to overcome two problems of vertical handover: wi-fi delays authentication and the ping pong, the risk of passing continuously from one network to another when the Wi-Fi signal is weak. The paradox: wi-fi was always considered by operators the enemy that could undermine the boom in mobile data traffic. The boom is arrived, too strong, and now they go to the Wi-Fi to get help.

.

Waiting to know if its use IS IMMUNE OR NOT from a legal standpoint, the new spanish router arrives on the European market at a price decidedly competitive: 59 euros for the new router enriched by a new firmware (2.2.5.0 flipper enduser) and new, interesting feature. The most interesting is undoubtedly the addition of support for popular USB air cards offering connectivity with 3G: With this feature you can then connect the router to air cards to spread via wireless connectivity to other devices.

Equipped with a LAN access more than in previous La Fonera 2.0 supports the 802.11 b/g/n wireless protocol provides full native compatibility with the most popular social networking services and file sharing: from YouTube to Facebook, from Flickr to Picasa, via BitTorrent , RapidShare and MegaUpload, not forgetting the chance to share with other computer scanners and printers. But FON is not only this: the feature that has most contributed the rise of Spanish in all likelihood is the revolutionary idea of shared social network.

La Fonera shares in two parts connectivity provided by the ISP: from one side the encrypted part (for the premises of the user), other side than one making available to the community, which may benefit from free (for registered service) or payment. In the latter case, the revenue generated will be divided equally between those who provides the bandwidth and the Spanish company.

Still in the field of wireless connectivity, it is expected the users would benefit with the partnership signed between Fring, one of the most widely used multi-platform IM client and WeFi service that maps all free hotspots in the area. Marriage between the two gave birth to a free plugin for the client Fring allows you to search for access points using (if any) the internal GPS to your mobile device or through the inclusion of its position on the map. At the time, according to Fring’s website, the plugin is only available for all devices with Symbian OS or Windows Mobile: It is not known at this time whether this is an update to the ever-growing user community with iPhone.

According to WeFi, there are already over 20 million hotspots accessible free of charge by the community of users using Fring, a number that should not be underestimated, since in many countries, mobile telephone providers do not seem to provide cheap solutions in the field of connectivity to the Web using the 3G network both for mobile and for laptop with air cards. “WeFi represents an exciting new opportunity for our selection of add-ons made for Fring, because it allows us to locate and access thousands of free hotspots all over the world in a very simple way, making the mobile web experience even more attractive for those who prefer the quality of the WiFi at no cost”, said Avi Shechter, CEO of Fring.