Wi Fi Offloading Technology Overview And Approaches

Offloading Technology Overview

The Third Generation Partnership Project (3GPP) has specified three different technologies capable of offloading 3GPP standardized mobile data networks (Global System for Mobile Communications (GSM)/ General Packet Radio Service (GPRS), Wideband Code Division Multiple Access (WCDMA), High Speed Packet Access (HSPA) etc. for Wi-Fi) to multimode terminals (with both 3GPP and Wi-Fi interfaces). These technologies are briefly described below.

i. Generic Access Network (GAN) also referred to as Unlicensed Mobile Access (UMA) whereby a GAN controller (GANC) is deployed in a mobile core network (simulating a radio network controller) to perform 3GPP WLAN vertical handover to UMA enabled terminals.

ii. Inter-working Wireless LAN (I-WLAN) which specifies interfaces for 3GPP and common control mechanisms (such as authentication) for WLAN interworking, and Packet Data Gateway (PDG) toprovided gateway functionality toprovided gateway functionality for WLAN access towards the 3GPP core network.

iii. Access Network Discovery and Selection Function (ANDSF), a unit within the 3GPP Evolved Packet Core (EPC), which provides the means for a mobile operator to define policies that determine how andsf enabled terminals can connect to non-3GPP access (WLAN, Worldwide Interoperability Microwaveaccess (WiMAX), etc.).

Wi-Fi Offloading Approaches

There are three main levels of integration between Wi-Fi networks and cellular networks, which are:

● Network bypass or un-managed data offloading, ● Managed data offloading, and ● Integrated offloading. The first approach is un-managed data offloading, or bypass offloading, considered the easiest type of offloading, where data is directed to Wi-Fi whenever coverage is not needed with no need for equipment installment. In this type of offloading, voice services will remain on the mobile core network. This immediate offloading solution suffers from various issues such as: 1) Operators will lose visibility, control over their own customers. 2) Operators will not be able to send subscribed content, which leads to lost revenue.

The second approach, managed data offloading, is used by operators who do not want to lose control of their customers, however, they are not allowed to send subscribed content. The third offloading approach is integrated data offloading, which empowers operators with full control over their customers, along with the ability to send subscribed content. The drawback of the latter offloading, is the need to install data that forms a bridge between a cellular network and a Wi-Fi network. Integrated offloading extends the coupling architecture concept to Wi-Fi with cellular systems, which can be divided into two coupling architectures: loose coupling and tight coupling.

Conclusion

Cellular/Wi-Fi integration and one of its outcomes namely Wi-Fi offload is a promising technology enhancement from both operator and end-user perspective. Its offerings are tremendous, and its true potential must be tapped. Wi-Fi offload in the true sense aims to be an end-user agnostic provider of seamless mobility and service. While it is still a long way to go to achieve these offload features, the standardization process witnesses that it is going to happen soon.

There are some important points that need to be considered for the effective deployment of Wi-Fi offload. One, the dawn of this technology can really be seen only when the Wi-Fi footprint in India grows to such a level that offload scenarios are feasible and economically attractive. Another important point that can be envisaged is to create policies to facilitate fair revenue sharing between Wi-Fi operators, mobile network operators and other entities to have a minimum dispute, if any. It should also be considered and evaluated whether Wi-Fi service providers, for integration and revenue sharing with licensed networks, will need some form of license obligations. Also, serious consideration needs to be given to the spectrum crunch that the 2.4 GHz band will face, once Wi-Fi offload solutions become widely deployed. To address this, some other bands should be explored considering their potential for Wi-Fi and can be considered as an excellent candidate for Wi-Fi deployment in the near future. Security considerations such as the impact of Wi-Fi offload solutions on location based services need to be thoroughly investigated and addressed.

Wi-Fi offloading offers many benefits for users, carriers, and their Wi-Fi network partners. At the same time, Wi-Fi offloading is complex and demands that carriers perform thorough testing to ensure a transparent, high-quality experience for customers. This includes providing a transparent, high-quality experience for users that is continuous even as user and application demands grow. These solutions must also be easy for service providers to deploy, including integration with existing customer billing systems and integrating with administration systems for ongoing management and monitoring.

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