Recursos VoIP - Enlaces

Fuente: Lucent Technologies
Formato: PDF

Internet telephony is viewed as an emerging technology not only for wireline networks, but also for third-generation wireless networks. Although IP end to end is considered the ultimate approach to future wireless voice services, there is still a long way to go before IP voice packets can be effectively transported over the air. Therefore, Internet telephony and today's circuit-switched wireless network will coexist for years to come, and it is essential to effectively perform interworking between these networks. This paper proposes the Unified Mobility Manager (UMM) that achieves efficient interworking between traditional wireless networks and Internet telephony networks.

Fuente: Lucent Technologies
Formato: PDF

Fourth generation mobile networks will allow end-users to roam over different network technologies, such as UMTS, CDMA2000 and Wi-Fi. These mobile networks have the ability to determine the location of the end-user, which is information that can be used by mobile applications to adapt their behavior. Each of the network technologies has its own way to determine the user location, and has its own way to provide this information to the end-user and/or mobile application. Developers of mobile applications however should not be exposed to the peculiarities of the different network technologies, and should be offered a network technology independent way to obtain the user location.

Fuente: National Institute of Standards and Technology
Formato: PDF

This paper presents a method of transmitting video over the cdma2000 mobile system. In this method, the video bit-stream after splitting, is transmitted via the supplemental channels of the cdma2000 reverse link. The method takes advantage of the direct spread multiplexing structure of the supplemental channels to transmit divided video at differing priority classes. This is accomplished by adopting the relative gain adjustment strategy where the most error sensitive video information is transmitted via a channel with higher power.

Fuente: Telcordia Technologies
Formato: PDF

Fuente: University of Antwerp
Formato: PDF

The high data rate WLAN standard IEEE 802.11b is experiencing a successful development. This success is drawn by two main types of networks: enterprise networks and hot spots, i.e., conference centers, railway stations, airports, hotels, etc. In both environments, VoIP and VoWLAN are becoming attractive technologies with the main goal to reduce the communication costs by merging data and voice networks.

Fuente: ShoreTel
Formato: PDF

Better accessibility is critical for salespeople and other front-line employees. The easier it is for them to respond quickly to customers and team members - no matter where they are at the time - the more effective they can be. This white paper describes how certain features of an IP telephony system, such as the call manager application, softphone, and find me capability, can have a huge impact on the bottom line.

Fuente: Symbol Technologies
Formato: PDF

In the last few years, the demand for wireless access to networks and the Internet has skyrocketed. This technology is called Wireless Fidelity (Wi-Fi). Now Wi-Fi extends to voice - known as Voice over Wi-Fi (VoWiFi). This new technology allows people to communicate wirelessly by voice over enterprise networks and the Internet - and a major force driving the acceptance of VoWiFi is the proliferation of voice-enabled digital handsets, PDAs (Personal Digital Assistants) and notebook PCs.

Fuente: University of Hong Kong
Formato: PDF

Today, most Wireless LANs (W LAN) are connected to the backbone via a wired Distribution System (DS). A Wireless Distribution System (WDS) provides quick and easy networking in circumstances that require temporary network services or when cabling is difficult, for example, in open area conversations, disasters and military usages. WDS can be used to extend the range of wireless service coverage. Transmitting Voice-over-IP (VoIP) traffic over WDS to a WLAN in the straightforward way may fail to fulfill the tight delay requirement, and may severely limit the system capacity. This paper extends the M-M scheme for WLAN connected via a WDS.

Fuente: ShoreTel
Formato: PDF

Mobility is often approached as an enabler of location independence, but freedom of location by itself doesn’t buy enterprise much. The real benefit of mobility is that, when enterprises need to do business, they can. Such immediate-response capability is achieved only when enterprises can reach or be reached by the right people and actually talk to them. Only then can enterprises truly leverage all that information at fingertips. This is what the right VoIP solution can bring to the table.

Fuente: Generics Group
Formato: PDF

The cost of third generation (3G) mobile phone technology to the world's mobile phone operators stands at $129 billion (September 2001), a fact that has arguably contributed to a major downfall (or at least slide) in some of the worlds most successful companies. But what is 3G, when will it arrive and what will we get when it does?

This paper provides the non-technical reader with an introduction to what 3G technology is. It attempts to unravel some of the confusion surrounding the plethora of standards, bodies and acronyms that are regularly used in the industry. Widespread availability of 3G services is predicted to take off in 2004. In the meantime, services need to be successful on 2.5G networks, which must coexist with 3G networks to support the frequent roaming of subscribers between them.

Fuente: Intersil
Formato: PDF

As Wireless-Fidelity (Wi-Fi, 802.11b), Bluetooth, GPS and Wide Area Network (WAN) radios make their way into the realm of the PDA, so too does the need for more effective battery management. That is, freedom from tethered access to information and the burden of carrying multiple gadgets for mobility. The quintessential dimension of this evolution is the expansion and availability of broadband wireless communication. And as network carriers like Verizon and Sprint PCS hustle to upgrade their base-stations to 3G and GPRS we are fast moving from a voice-centric mobile society to one that is data-centric.

Fuente: SpectraLink
Formato: PDF

This paper introduces concept of Wi-Fi Telephony. The incredible growth of two leading technologies, wireless LAN and voice over IP, has come together to provide an exciting new application, Wi-Fi Telephony.

Fuente: VeriSign
Formato: PDF

This white paper, which addresses the opportunity to provide an integrated voice-over-internet-protocol (VoIP)/cellular service, will discuss the growth in mobility users, advances in cellular and Wi-Fi technologies, and the introduction of dual-mode handsets and how this combination of mobility growth and technology advancements presents an opportunity for landline mobility services. It will also discuss how VeriSign is addressing the converged opportunity with the VeriSign Wireless IP Connect Service currently available for customer evaluation and testing.

Fuente: Alcatel
Formato: PDF

With Wi-Fi becoming increasingly available at home, at the office and at public hotspots, users have many opportunities to test it. Typically, users try it on the road, demand it at work and buy it for their homes, with each activity spurring increased usage in the other markets. Moreover, Wi-Fi is educating users for the mobile broadband wireless market, initiating them to the capabilities of 3G/UMTS. Indeed, Wi-Fi, with its true broadband capabilities and growing penetration in the home, the enterprise and public hotspots, may well become pervasive. Market take -up is accelerating, pushed both by the low cost of Wi-Fi radio access systems and by the generalized availability of the Wi-Fi interface in new-generation PDAs and PCs.

Fuente: Springer Science+Business Media
Formato: PDF

The Internet has been growing tremendously in the recent years and applications like web browsing are becoming increasingly popular. In a collective effort to provide seamless access to the Internet, wireless equipment manufacturers and service providers are developing 3G wireless systems that efficiently support current and future Internet applications. This paper evaluates the performance and capacity of a 3G wireless data system based on IS-2000 standard. The paper considers web browsing as the common application for all users and evaluates the system performance for single and parallel web browsing sessions.