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The goal laid out for telecommunication industry is to keep end-users ‘always best connected’.
Vendors and service providers envision always best connected coverage for multimode devices containing many wireless access technologies, e.g. Bluetooth, Wi-Fi, WiMAX, 2.5G and 3G mobile. This requires a level of interoperability and cooperation never seen before. Each technology has its own advantages and disadvantages, so being best connected means using the technology with the optimum signal and bandwidth characteristics for the application in use; and perhaps thereafter, the ability to handover between technologies.
To achieve the always best-connected scenario users will mix and match mobile platforms and wireless technologies to meet their unique requirements, enabling them to stay connected virtually anytime and anywhere.
Broadband wireless can reach the always best connected goal through the following scenario:
• all types of wireless networks will be deployed around the globe;
• Wi-Fi hotspots will proliferate in public places, businesses and homes;
• homes and businesses will add UWB (when available) for the fastest distribution of high-definition content;
• first-generation WiMAX technology will be broadly deployed to provide long-distance broadband connectivity for Wi-Fi hotspots, as well as cellular and enterprise backhaul;
• 802.16e WiMAX connectivity will be added in densely populated areas to provide a canopy of wireless broadband data access to mobile laptop users;
• innovations in 3G technologies will add ground-breaking data capabilities to mobile handset and handheld PC users.
Roaming and Seamless Handoff
Key to future impact of convergence is seamless handoff between disparate data networks, i.e. handoffs between Wi-Fi (802.11) networks and 3G mobile networks (CDMA2000® and UMTS), between 3G networks and 802.16 networks or between Wi-Fi (802.11) networks and 802.16 networks. The initial deployments of the 802.16d system
THE ROAD AHEAD
will be a fixed point to fixed multipoint deployment. In this case, roaming will be handled from the fixed subscriber station distribution system and the users’ communication platform, in much the same way as roaming from a DSL or cable modem is implemented. Once the 802.16e systems become available and certified, roaming will be accomplished in the same manner as roaming between 3G and Wi-Fi.
Enabling such ubiquitously connected devices poses numerous difficult technology challenges. These include:
• Multiple radio integration and coordination - building the handset (or other device) begins with the challenge of integrating multiple radios.
• Intelligent networking, seamless roaming and handoff - users will expect to roam within and between networks, as they do with their cell phone.
• Power management - as handsets and other devices evolve to run more richer applications, power management will become an even greater challenge.
• Support for cross-network identity and authentication - providing a trusted, efficient and usage-model appropriate means of establishing identity is one of the key issues in cross-network connectivity.
• Support for rich media types - the addition of a high-bandwidth broadband wireless connection, such as WLAN or some of the forthcoming UMTS or EVDV/O cellular networks will open up new opportunities for the delivery of rich media to handheld devices.
• Flexible, powerful computing platform - the foundation of a universal communicator-class device must be a flexible, powerful, general-purpose processing platform.
• Overall device usability - the final challenge inherent in building a mixed-network device is usability (Figure 6.13).
New business initiatives and competitive pressures to become more efficient and productive are forcing enterprises to seek new types of
Figure 6.13 Next-generation network
network services. In particular, enterprises are showing significant interest in advanced data services, and are adopting such offerings as metro Ethernet services, IP VPNs, Layer 2 VPNs and VoIP technology as a replacement for traditional PBXs.
At the same time, carriers continue to rely heavily on the more traditional voice and data services that are well understood and widely deployed throughout their networks. Changes in customer demands are causing carriers to dramatically alter the way they design their networks. In addition, carrier requirements to cut their costs - both operational and capital expenses - are causing further reevaluation of networks.
The best network solutions for carriers are ones that meet their customers’ needs for next-generation services and also address their own requirements for lower capital and operational costs. Enabling new
THE ROAD AHEAD
services, while maintaining legacy services, is critical for their success in moving forward.
As voice and legacy data service revenue declines, carriers need new services to fill the revenue void. More importantly, enterprise customers are demanding new services from their service providers. If the incumbent provider does not have what a customer needs, they will spend their money with a new service provider that does offer it.