With Third Generation (3G), the information is split into separate but related "packets" before being transmitted and reassembled at the receiving end. Packet switched data formats are much more common than their circuit switched counterparts. Other examples of packet-based data standards include TCP/IP, X.25, Frame Relay and Asynchronous Transfer Mode (ATM). As such, whilst packet switching is new to the GSM world, it is well established elsewhere. In the mobile world, CDPD (Cellular Digital Packet Data), PDCP (Personal Digital Cellular Packet), General Packet Radio Service (GPRS) and wireless X.25 technologies have been in operation for several years. X.25 is the international public access packet radio data network standard.

The World Wide Web is becoming the primary communications interface. People access the Internet for entertainment and information collection, the Intranet for accessing company information and connecting to colleagues and the Extranet for accessing customers and suppliers. These are all derivatives of the World Wide Web aimed at connecting different communities of interest. There is a trend away from storing information locally in specific software packages on PCs to remotely on the Internet.

Speeds of up to 2 Megabits per second (Mbps) are achievable with Third Generation (3G). The data transmission rates will depend upon the environment the call is being made in. It is only indoors and in stationary environments that these types of data rate will be available. For high mobility, data rates of 144 kbps are expected to be available. This is only about three times the speed of todays fixed telecoms modems.

Third Generation (3G) facilitates several new applications that have not previously been readily available over mobile networks due to the limitations in data transmission speeds. These applications range from Web Browsing to file transfer to Home Automation - the ability to remotely access and control in-house appliances and machines. Because of the bandwidth increase, these applications will be even more easily available with 3G than they were previously with interim technologies such as GPRS.

Use of Third Generation (3G) must be enabled for that user. Automatic access to the 3G may be allowed by some mobile network operators, others will charge a monthly subscription and require a specific opt-in to use the service as they do with other non-voice mobile services.

The telecommunications world is changing as the trends of media convergence, industry consolidation, Internet and IP technologies and mobile communications collide into one. Significant change will be bought about by this rapid evolution in technology. Third Generation mobile Internet technology is a radical departure from the first and the second generations of mobile technology. Some of the changes include:

Mobile communications will be similar in its capability to fixed communications, such that many people will only have a mobile phone. The mobile phone will be used as an integral part of the many peoples' lives. It could become a core part of how they conduct their daily activities.

3G is based on a different technology platform- Code Division Multiple Access (CDMA)- that is unlike the Time Division Multiple Access (TDMA) technology that is widely used in the 2G world. GSM (Global System for Mobile Communications) was based on TDMA technology.

Many industry analysts and other pundits have questioned the return on an investment in 3G technology- questioning whether network operators will be able to earn an adequate return on the capital deployed in acquiring and rolling out a 3G network.

First-generation wireless mobile communication systems, introduced in the early 1980s, and second generation (2G) systems, fielded in the late 1980s, were intended primarily for voice transmission. Third-generation (3G) systems, to be introduced in the early 2000s, will offer considerably higher data rates and allow significantly increased flexibility over 2G systems. A feature of 3G wireless mobile systems will be to provide this wide variety of services ranging from voice and paging services to interactive multimedia, including teleconferencing and Internet access through a coordinated or transparent system concept - by fixed wireline where that is most efficient, by terrestrial wireless where required, and even by satellite wireless when necessary. The currently proposed 3G systems will, for the most part, not achieve this coordinated system vision or Global seamless roaming, leaving these as goals for fourth generation (4G) and beyond.

Projection beyond 3G wireless mobile systems naturally leads to the consideration of yet wider bandwidths and higher data rates. However, higher data rates will not necessarily provide additional overall capacity for a number of reasons. First, it is by no means clear how system resources should be managed to accommodate the wide mix of traffic types anticipated. Second, power limitations preclude high data rates over geographically large areas, and a hierarchy of cell structures or ad hoc wireless networks to accommodate those users desiring high data-rate services will be necessary. Third, because of the variability of wideband channels and the need to realize the maximum inherent diversity possible, joint adaptivity across several hierarchical layers is necessary, and an integrated research approach is important to resolve the technical tradeoffs. Fourth, in contrast to purely wireline networks, scalability, or the ability to handle increasing numbers of users and diversity of services, is more challenging with mobile networks. A scalable information infrastructure is clearly essential in any future interconnected information system.

It appears reasonable to expect an extension of the capacity of 3G wireless systems by at least an order of magnitude with 4G systems and beyond. The focus of this initiative is to address fundamental research issues, which are critical to these future generation wireless systems. Several attendant benefits and applications of this increased capacity are outlined below.

Advanced features of wireless mobile systems, including data rates compatible with multimedia applications, global roaming capability, and coordination with other network structures, will enable applications not possible with current and previous wireless mobile systems such as:

(a) Virtual navigation: A remote database contains the graphical representation of streets, buildings, and physical characteristics of a large metropolis. Blocks of this database are transmitted in rapid sequence to a vehicle, where a rendering program permits the occupants to visualize the environment ahead. They may also "virtually" see the internal layout of buildings to plan an emergency rescue, or to plan visits to possible points of interest.

(b) Tele-medicine: The paramedic assisting the victim of a traffic accident in a remote location must access medical records (e.g., x-rays) and may need video conference assistance from a surgeon for an emergency intervention. In fact, the paramedic may need to relay back to the hospital the victim's x-rays taken locally.

(c) Tele-geoprocessing applications: The combination of geographical information systems (GIS), global positioning systems (GPS), and high-capacity wireless mobile systems will enable a new type of application referred to as tele-geoprocessing. Queries dependent on location information of several users, in addition to temporal aspects have many applications.

(d) Crisis-management applications: These arise, for example, as a result of natural disasters where the entire communications infrastructure is in disarray. Restoring communications quickly is essential. With wideband wireless mobile communications, limited and even total communications capability, including internet and video services, could be set up in hours instead of days or even weeks required for restoration of wireline communications.

(e) Education via the internet: educational opportunities available on the internet, both for K-12 pupils and individuals interested in life-long education, will be unavailable to clientele living in thinly populated or remote areas because of the economic unfeasibility of providing wideband wireline internet access in these areas. Wideband wireless communications provides a cost-effective alternative in these situations.

Significant advances in basic research to provide a foundation for designing high information-capacity wireless communication systems for full mobility will require synergistic, multidisciplinary research efforts encompassing a breadth of communications functions from the physical through application layers. Such research would be expected to lead to breakthroughs enabling future wireless networks to be flexible, scalable to large numbers of users, able to provide location information of mobile users on a global scale, eavesdropper proof, coordinated with wireline and other networks, dynamically adaptable with demand, and able to provide guaranteed service while accommodating mixed traffic representing varied applications.

Proposals for research to investigate system design approaches and principles addressing the unique requirements and characteristics of future high throughput, mixed traffic, highly mobile communication systems are encouraged. Example areas for consideration include, but need not be limited to, network topologies for supporting integrated services, adaptive data flow at the physical and higher layers, joint optimisation of multiple adaptive subsystems, dynamic resource allocation schemes, means for exploiting mobile/base unit asymmetry, security/privacy across the layers (physical through applications), and dynamic support for quality of service.

Other issues that are important to consider include methods for realising the inherent diversity of temporally and spatially varying channels (such as space-time processing, smart antennas, etc.), optimisation techniques for statistical channel models applicable to wideband signals, network protocols that adapt dynamically to changing channel conditions, protocols that allow the coexistence of low- and high-rate users, hand-off of high-data-rate users between base stations, congestion-control algorithms that are cognisant of and adjust to changing channel conditions, and coordination of adaptation across layers.

Finally, it is important to consider the interplay between high-capacity wireless networks and wireless mobile information systems. Such applications include, but are not limited to, ubiquitous information processing, virtual collaboration and visualisation, semantic routing for information discovery, protocols for content/capability adaptation, application and system adaptability to network bandwidth variability (e.g., error rates in transition and handoffs, fault tolerance and recovery, query optimisation, management of power limitations, transaction management, and security), ability to continue operation during disconnection (e.g., via caching), smart push/pull techniques based on user profiles using multicast network protocols and mixed bandwidth links, and seamless environments for remote sensing, including use of GIS and GPS.