Mobile data offloading
Encyclopedia
Mobile data offloading, also called data offloading is the use of complementary network technologies for delivering data originally targeted for cellular network
s. Rules triggering the mobile offloading action can either be set by an end-user (mobile subscriber) or an operator. The code operating on the rules resides in an end user device, in a server or it is divided between the two. For the end users the purpose for doing mobile data offloading is based on data service cost control and availability of higher bandwidth. For the operators the main purpose for the offloading is congestion of the cellular networks. The main complementary network technologies used for the mobile data offloading are Wi-Fi
, Femtocell
and Integrated Mobile Broadcast
.
It is predicted that the mobile data offloading will become a new industry segment. This is due to surge of the mobile data..
devices possessing Wi-Fi
capabilities together with large screens and different Internet applications from browsers to video and audio streaming applications. In addition to smart phones laptops with 3G access capabilities are also seen as one major source mobile data traffic. It has been estimated that the total Internet traffic will pass 500 Exabytes/year milestone in 2013. Annual growth rate of 50% is expected to continue and it will keep out phasing the respected revenue growth .
as the
prime example, and by the consolidation of Wi-Fi network operators .
3GPP
based Enhanced Generic Access Network (EGAN) architecture applies tight coupling as it specifies rerouting of cellular network signaling through Wi-Fi access networks. This makes Wi-Fi a de-facto 3GPP RAN. 3GPP has also specified an alternative loosely coupled solution for Wi-Fi. The approach is called Interworking Wireless LAN (IWLAN) architecture and it is a solution to transfer IP data between a mobile device and operator’s core network through a Wi-Fi access. In the IWLAN architecture, a mobile device opens a VPN/IPsec tunnel from the device to the dedicated IWLAN server in the operator’s core network to provide the user either an access to the operator’s walled-garden services or to a gateway to the public Internet. With loose coupling between the networks the only integration and interworking point is the common authentication architecture.
The most straightforward way to offload data to the Wi-Fi networks is to have a direct connection to the public Internet. This no coupling alternative omits the need for interworking standardization. For majority of the web traffic there is no added value to route the data through the operator core network. In this case the offloading can simply be carried out by switching the IP traffic to use the Wi-Fi connection in mobile client instead of the cellular data connection. In this approach the two networks are in practice totally separated and network selection is done by a client application. Studies show that significant amount of data can be offloaded in this manner to Wi-Fi networks even when users are mobile .
(ANDSF) is the most complete 3GPP approach to date for controlling offloading between 3GPP and non-3GPP access networks (such as Wi-Fi). The purpose of the ANDSF is to assist user devices to discover access networks in their vicinity and to provide rules (policies) to prioritize and manage connections to all networks.
technology. The forum also works to ensure interoperability among vendors and service providers.
Cellular network
A cellular network is a radio network distributed over land areas called cells, each served by at least one fixed-location transceiver known as a cell site or base station. When joined together these cells provide radio coverage over a wide geographic area...
s. Rules triggering the mobile offloading action can either be set by an end-user (mobile subscriber) or an operator. The code operating on the rules resides in an end user device, in a server or it is divided between the two. For the end users the purpose for doing mobile data offloading is based on data service cost control and availability of higher bandwidth. For the operators the main purpose for the offloading is congestion of the cellular networks. The main complementary network technologies used for the mobile data offloading are Wi-Fi
Wi-Fi
Wi-Fi or Wifi, is a mechanism for wirelessly connecting electronic devices. A device enabled with Wi-Fi, such as a personal computer, video game console, smartphone, or digital audio player, can connect to the Internet via a wireless network access point. An access point has a range of about 20...
, Femtocell
Femtocell
In telecommunications, a femtocell is a small cellular base station, typically designed for use in a home or small business. It connects to the service provider’s network via broadband ; current designs typically support 2 to 4 active mobile phones in a residential setting, and 8 to 16 active...
and Integrated Mobile Broadcast
Integrated Mobile Broadcast
Integrated Mobile Broadcast is a mobile wireless technology that enables broadcast of content at the cellular transmitter level, using the 3G or 4G licenced radio spectrum, and received on mobile terminals....
.
It is predicted that the mobile data offloading will become a new industry segment. This is due to surge of the mobile data..
Mobile data surge
Increasing need for offloading solutions is caused by the explosion of the Internet data traffic and especially the growing portion of the traffic going through mobile networks. This has been enabled by smart phoneSmartphone
A smartphone is a high-end mobile phone built on a mobile computing platform, with more advanced computing ability and connectivity than a contemporary feature phone. The first smartphones were devices that mainly combined the functions of a personal digital assistant and a mobile phone or camera...
devices possessing Wi-Fi
Wi-Fi
Wi-Fi or Wifi, is a mechanism for wirelessly connecting electronic devices. A device enabled with Wi-Fi, such as a personal computer, video game console, smartphone, or digital audio player, can connect to the Internet via a wireless network access point. An access point has a range of about 20...
capabilities together with large screens and different Internet applications from browsers to video and audio streaming applications. In addition to smart phones laptops with 3G access capabilities are also seen as one major source mobile data traffic. It has been estimated that the total Internet traffic will pass 500 Exabytes/year milestone in 2013. Annual growth rate of 50% is expected to continue and it will keep out phasing the respected revenue growth .
Alternatives
Wi-Fi and Femtocell technologies are the primary candidates by the industry. In addition there are WiMax and terrestrial networks (LAN) offloading for 3G. The Femtocells use the standard cellular radio technologies thus each mobile is capable of participating in the data offloading process, though some modification is needed to accommodate the different backhaul . On the other hand, the cellular radio technologies are founded on the ability to do network planning within licensed spectrum. Hence, it may turn out to be difficult, both technically and business wise, to mass deploy Femtocell access points. Self Organizing Network (SON) is an emerging technology for tackling e.g. unplanned Femtocell deployment. Wi-Fi technology is different radio technology to cellular but most Internet capable mobiles devices now come with WiFi capability. There are already millions of installed Wi-Fi networks mainly is congested areas such as airports, hotels and city centers and the number is growing rapidly . The Wi-Fi networks are very fragmented but recently there has been efforts to consolidate WiFi networks. The consolidation of the WiFi networks proceeds through community approach, FONFON
Fon is a company that operates a system of dual access wireless networks. Fon is the largest Wi-Fi network in the world, with over 4 million hotspots....
as the
prime example, and by the consolidation of Wi-Fi network operators .
Wi-Fi
Wi-Fi offloading is an emerging business domain with multiple companies entering to the market with proprietary solutions. As standardization has focused on degree of coupling between the cellular and WiFi networks. The competing solutions can be classifying based on the minimum needed level of network interworking. A further classification criterion is the initiator of the offloading procedure.Cellular and Wi-Fi network interworking
Depending on the services to be offloaded and the business model there may be a need for interworking standardization. Standardization efforts have focused on specifying tightly or loose coupling between the cellular and the WiFi networks.3GPP
3GPP
The 3rd Generation Partnership Project is a collaboration between groups of telecommunications associations, known as the Organizational Partners...
based Enhanced Generic Access Network (EGAN) architecture applies tight coupling as it specifies rerouting of cellular network signaling through Wi-Fi access networks. This makes Wi-Fi a de-facto 3GPP RAN. 3GPP has also specified an alternative loosely coupled solution for Wi-Fi. The approach is called Interworking Wireless LAN (IWLAN) architecture and it is a solution to transfer IP data between a mobile device and operator’s core network through a Wi-Fi access. In the IWLAN architecture, a mobile device opens a VPN/IPsec tunnel from the device to the dedicated IWLAN server in the operator’s core network to provide the user either an access to the operator’s walled-garden services or to a gateway to the public Internet. With loose coupling between the networks the only integration and interworking point is the common authentication architecture.
The most straightforward way to offload data to the Wi-Fi networks is to have a direct connection to the public Internet. This no coupling alternative omits the need for interworking standardization. For majority of the web traffic there is no added value to route the data through the operator core network. In this case the offloading can simply be carried out by switching the IP traffic to use the Wi-Fi connection in mobile client instead of the cellular data connection. In this approach the two networks are in practice totally separated and network selection is done by a client application. Studies show that significant amount of data can be offloaded in this manner to Wi-Fi networks even when users are mobile .
Initiation of offloading procedure
There are three main initiation schemes: WLAN scanning initiation, user initiation and remotely managed initiation. In the WLAN scanning based initiation the user device performs periodically WLAN scanning. When a known or an open Wi-Fi network is found an offloading procedure is initiated. In the user initiated mode a user is prompted to select, which network technology is used. This happens usually once per a network access session. In the remotely managed approach a network server initiates each offloading procedure by prompting the connection manager of a specific user device. Operator managed is a subclass of the remotely managed approach. In the operator managed approach operator is monitoring its network load and user behavior. In the case of the forthcoming network congestion the operator initiates the offloading procedure.ANDSF
Access Network Discovery and Selection FunctionAccess Network Discovery and Selection Function
Access network discovery and selection function is an entity within an evolved packet core of the system architecture evolution for 3GPP compliant mobile networks...
(ANDSF) is the most complete 3GPP approach to date for controlling offloading between 3GPP and non-3GPP access networks (such as Wi-Fi). The purpose of the ANDSF is to assist user devices to discover access networks in their vicinity and to provide rules (policies) to prioritize and manage connections to all networks.
Operating System Connection Manager
Many operating systems provide a connection manager that can automatically switch to WiFi network if the connection manager detects a known Wi-Fi network. Such functionality can be found from most modern operating systems (for example from all Windows versions beginning from XP SP3, Ubuntu, Nokia N900 and Apple iPhone). The connection managers do not require coupling of the cellular and the WiFi networks.Femtocell offloading
Femtocell forum is an industry forum promoting mobile data offloading for 3G/4G network using FemtocellFemtocell
In telecommunications, a femtocell is a small cellular base station, typically designed for use in a home or small business. It connects to the service provider’s network via broadband ; current designs typically support 2 to 4 active mobile phones in a residential setting, and 8 to 16 active...
technology. The forum also works to ensure interoperability among vendors and service providers.