Mobile data offloading

Last updated

Mobile data offloading is the use of complementary network technologies for delivering data originally targeted for cellular networks. Offloading reduces the amount of data being carried on the cellular bands, freeing bandwidth for other users. It is also used in situations where local cell reception may be poor, allowing the user to connect via wired services with better connectivity.

Contents

Rules triggering the mobile offloading action can be set by either an end-user (mobile subscriber) or an operator. [1] The code operating on the rules resides in an end-user device, in a server, or is divided between the two. End users do data offloading for data service cost control and the availability of higher bandwidth. The main complementary network technologies used for mobile data offloading are Wi-Fi, femtocell and Integrated Mobile Broadcast. It is predicted[ by whom? ] that mobile data offloading will become a new industry segment due to the surge of mobile data traffic. [2] [ timeframe? ]

Mobile data surge

Increasing need for offloading solutions is caused by the explosion of Internet data traffic, especially the growing portion of traffic going through mobile networks. This has been enabled by smartphone 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 a major source of mobile data traffic. Additionally, Wi-Fi is typically much less costly to build than cellular networks. [3] It has been estimated that the total Internet traffic would pass 235.7 Exabytes per month in 2021, up from 73.1 Exabytes per month in 2016. [4] Annual growth rate of 50% is expected to continue and it will keep out phasing the respected revenue growth. [5] [6] [ timeframe? ]

Alternatives

Wi-Fi and femtocell technologies are the primary offload technologies used by the industry. [7] In addition, WiMax [8] and terrestrial networks (LAN) [9] are also candidates for offloading of 3G mobile data. Femtocells use standard cellular radio technologies, thus any mobile device is capable of participating in the data offloading process, though some modification is needed to accommodate the different backhaul connection. [7] On the other hand, 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) [10] is an emerging technology for tackling unplanned femtocell deployment (among other applications). Wi-Fi technology is different radio technology than cellular, but most Internet capable mobile devices now come with Wi-Fi capability. There are already millions of installed Wi-Fi networks mainly in congested areas such as airports, hotels and city centers and the number is growing rapidly. [11] Wi-Fi networks are very fragmented but recently there have been efforts to consolidate them. The consolidation of Wi-Fi networks is proceeding both through a community approach, Fon as the prime example, and by the consolidation of Wi-Fi network operators. [12] [ timeframe? ]

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 Wi-Fi networks, the competing solutions can be classified based on the minimum needed level of network interworking. Besides standardization, research communities have been exploring more open and programmable design in order to fix the deployment dilemma. [13] [14] [15] A further classification criterion is the initiator of the offloading procedure.[ citation needed ]

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 Wi-Fi networks, especially in a network-controlled manner. [16] 3GPP based Enhanced Generic Access Network () [17] architecture applies tight coupling as it specifies rerouting of cellular network signaling through Wi-Fi access networks. Wi-Fi is considered to be a non-3GPP WLAN radio access network (RAN). [18] 3GPP has also specified an alternative loosely coupled solution for Wi-Fi. The approach is called Interworking Wireless LAN (IWLAN) [19] 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.[ timeframe? ]

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. [20] [21] [ timeframe? ] [22]

However, offloading does not always mean reduction of resource consumption (required system capacity) in the network of the operator. Under certain conditions and due to an increase of the burstiness of the non-offloaded traffic (i.e. traffic that eventually reaches the network of the operator in a regular way), the amount of network resources to offer a given level of QoS is increased. [23] In this context, the distribution of offloading periods turns out to be the main design parameter to deploy effective offloading strategies in the network of MNOs making non-offloaded traffic less heavy-tailed, hence reducing the resources needed in the network of the operator.[ timeframe? ]. The energy consumption in offloading is also another concern. [24]

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 periodically performs 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, the operator is monitoring its network load and user behavior. In the case of forthcoming network congestion, the operator initiates the offloading procedure.

ANDSF

Access network discovery and selection function (ANDSF) is the most complete 3GPP approach to date [25] 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.[ timeframe? ]

ATSSS

3GPP has started to standardize the Access Traffic Steering, Switching & Splitting (ATSSS) function to enable 5G devices to use different types of access networks, including Wi-Fi. The ATSSS service leverages the Multipath TCP protocol to enable 5G devices to simultaneously utilize different access networks. Experience with the utilisation of Multipath TCP on iPhones has shown that the ability to simultanesouly use Wi-Fi and cellular was key to provide support seamless handovers. The first version of the ATSSS specification leverages the 0-rtt convert protocol developed within the IETF. A prototype implementation of this service has been demonstrated in August 2019.

Operating system connection manager

Many operating systems provide a connection manager that can automatically switch to Wi-Fi 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, Android and Apple iPhone). The connection managers use various heuristics to detect the best performing network connections. These include performing DNS requests for known names over the newly activated network interfaces, sending queries to specific servers, ... When both the Wi-Fi and the cellular interfaces are activate, Android smartphones will usually prefer the Wi-Fi one since it is usually unmetered. When such a smartphone decides to switch from one interface to another, all the active TCP connections need to be reestablished.[ citation needed ]

Multipath TCP solves this handover problem in a clean way. With Multipath TCP, TCP connections can use both the Wi-Fi interface and the cellular one during the handover. [26] This means that ongoing TCP connections are not stopped when the smartphone decides to switch from one network to another. As of January 2020, Multipath TCP is natively supported on iPhones, but less frequently used on Android smartphones except in South Korea. On iPhones since iOS9, the Wi-Fi Assist subsystem monitors the quality of the underlying network connection. If the quality drops below a given threshold, Wi-Fi Assist may decide to move established Multipath TCP connections to another interface. Initially, this feature was used for the Siri application. Since iOS12, any [Multipath TCP] enabled application can benefit from this feature. Since iOS13, Apple Maps and Apple Music can also be offloaded from Wi-Fi to cellular and vice versa without any interruption.[ citation needed ]

Opportunistic offloading

With the increasing availability[ when? ] of inter-device networks (e.g. Bluetooth or WifiDirect) there is also the possibility of offloading delay tolerant data to the ad hoc network layer. In this case, the delay tolerant data is sent to only a subset of data receivers via the 3G network, with the rest forwarded between devices in the ad hoc layer in a multi-hop fashion. As a result, the traffic on the cellular network is reduced, or gets shifted to inter-device networks. [27] [ timeframe? ] [28]

See also

Related Research Articles

<span class="mw-page-title-main">Wireless network</span> Computer network not fully connected by cables

A wireless network is a computer network that uses wireless data connections between network nodes. Wireless networking allows homes, telecommunications networks and business installations to avoid the costly process of introducing cables into a building, or as a connection between various equipment locations. Admin telecommunications networks are generally implemented and administered using radio communication. This implementation takes place at the physical level (layer) of the OSI model network structure.

<span class="mw-page-title-main">WiMAX</span> Wireless broadband standard

Worldwide Interoperability for Microwave Access (WiMAX) is a family of wireless broadband communication standards based on the IEEE 802.16 set of standards, which provide physical layer (PHY) and media access control (MAC) options.

<span class="mw-page-title-main">Wi-Fi hotspot</span> Wi-Fi access point

A hotspot is a physical location where people can obtain Internet access, typically using Wi-Fi technology, via a wireless local-area network (WLAN) using a router connected to an Internet service provider.

<span class="mw-page-title-main">Voice over WLAN</span>

Voice over Wireless LAN (VoWLAN), also Voice over WiFi (VoWiFi), is the use of a wireless broadband network according to the IEEE 802.11 standards for the purpose of vocal conversation. In essence, it is Voice over IP (VoIP) over a Wi-Fi network. In most cases, the Wi-Fi network and voice components supporting the voice system are privately owned.

<span class="mw-page-title-main">Assisted GNSS</span> System to improve the time-to-first-fix of a GNSS receiver

Assisted GNSS (A-GNSS) is a GNSS augmentation system that often significantly improves the startup performance—i.e., time-to-first-fix (TTFF)—of a global navigation satellite system (GNSS). A-GNSS works by providing the necessary data to the device via a radio network instead of the slow satellite link, essentially "warming up" the receiver for a fix. When applied to GPS, it is known as assisted GPS or augmented GPS. Other local names include A-GANSS for Galileo and A-Beidou for BeiDou.

Devicescape is an American developer of client/server software services for wireless networking connectivity, analytics, and context-awareness. Founded in 2001 as Instant802 Networks, the company was renamed to Devicescape in January 2005. Devicescape is a venture backed private company.

Vertical handover or vertical handoff refers to a network node changing the type of connectivity it uses to access a supporting infrastructure, usually to support node mobility. For example, a suitably equipped laptop might be able to use both high-speed wireless LAN and cellular technology for Internet access. Wireless LAN connections generally provide higher speeds, while cellular technologies generally provide more ubiquitous coverage. Thus the laptop user might want to use a wireless LAN connection whenever one is available and to revert to a cellular connection when the wireless LAN is unavailable. Vertical handovers refer to the automatic transition from one technology to another in order to maintain communication. This is different from a horizontal handover between different wireless access points that use the same technology.

Generic Access Network (GAN) is a protocol that extends mobile voice, data and multimedia applications over IP networks. Unlicensed Mobile Access (UMA) is the commercial name used by mobile carriers for external IP access into their core networks. The latest generation system is named Wi-Fi calling or VoWiFi by a number of handset manufacturers, including Apple and Samsung, a move that is being mirrored by carriers like T-Mobile US and Vodafone. The service is dependent on IMS, IPsec, IWLAN and ePDG.

Mobile VoIP or simply mVoIP is an extension of mobility to a voice over IP network. Two types of communication are generally supported: cordless telephones using DECT or PCS protocols for short range or campus communications where all base stations are linked into the same LAN, and wider area communications using 3G or 4G protocols.

<span class="mw-page-title-main">Femtocell</span> Small, low-power cellular base station

In telecommunications, a femtocell is a small, low-power cellular base station, typically designed for use in a home or small business. A broader term which is more widespread in the industry is small cell, with femtocell as a subset. It connects to the service provider's network via broadband ; current designs typically support four to eight simultaneously active mobile phones in a residential setting depending on version number and femtocell hardware, and eight to sixteen mobile phones in enterprise settings. A femtocell allows service providers to extend service coverage indoors or at the cell edge, especially where access would otherwise be limited or unavailable. Although much attention is focused on WCDMA, the concept is applicable to all standards, including GSM, CDMA2000, TD-SCDMA, WiMAX and LTE solutions.

A wide variety of different wireless data technologies exist, some in direct competition with one another, others designed for specific applications. Wireless technologies can be evaluated by a variety of different metrics of which some are described in this entry.

<span class="mw-page-title-main">Mobile broadband</span> Marketing term

Mobile broadband is the marketing term for wireless Internet access via mobile networks. Access to the network can be made through a portable modem, wireless modem, or a tablet/smartphone or other mobile device. The first wireless Internet access became available in 1991 as part of the second generation (2G) of mobile phone technology. Higher speeds became available in 2001 and 2006 as part of the third (3G) and fourth (4G) generations. In 2011, 90% of the world's population lived in areas with 2G coverage, while 45% lived in areas with 2G and 3G coverage. Mobile broadband uses the spectrum of 225 MHz to 3700 MHz.

The 3GPP has defined the Voice Call Continuity (VCC) specifications in order to describe how a voice call can be persisted, as a mobile phone moves between circuit switched and packet switched radio domains.

Proxy Mobile IPv6 is a network-based mobility management protocol standardized by IETF and is specified in RFC 5213. It is a protocol for building a common and access technology independent of mobile core networks, accommodating various access technologies such as WiMAX, 3GPP, 3GPP2 and WLAN based access architectures. Proxy Mobile IPv6 is the only network-based mobility management protocol standardized by IETF.

A mobile broadband modem, also known as wireless modem or cellular modem, is a type of modem that allows a personal computer or a router to receive wireless Internet access via a mobile broadband connection instead of using telephone or cable television lines. A mobile Internet user can connect using a wireless modem to a wireless Internet Service Provider (ISP) to get Internet access.

Access network discovery and selection function (ANDSF) is an entity within an evolved packet core (EPC) of the system architecture evolution (SAE) for 3GPP compliant mobile networks. The purpose of the ANDSF is to assist user equipment (UE) to discover non-3GPP access networks – such as Wi-Fi or WIMAX – that can be used for data communications in addition to 3GPP access networks and to provide the UE with rules policing the connection to these networks.

<span class="mw-page-title-main">Small cell</span> Cellular network infrastructure

Small cells are low-powered cellular radio access nodes that operate in spectrum that have a range of 10 meters to a few kilometers. They are base stations with low power consumption and cheap cost. They can provide high data rates by being deployed densely to achieve high spatial spectrum efficiency.

Multipath TCP (MPTCP) is an ongoing effort of the Internet Engineering Task Force's (IETF) Multipath TCP working group, that aims at allowing a Transmission Control Protocol (TCP) connection to use multiple paths to maximize throughput and increase redundancy.

LTE in unlicensed spectrum is an extension of the Long-Term Evolution (LTE) wireless standard that allows cellular network operators to offload some of their data traffic by accessing the unlicensed 5 GHz frequency band. LTE-Unlicensed is a proposal, originally developed by Qualcomm, for the use of the 4G LTE radio communications technology in unlicensed spectrum, such as the 5 GHz band used by 802.11a and 802.11ac compliant Wi-Fi equipment. It would serve as an alternative to carrier-owned Wi-Fi hotspots. Currently, there are a number of variants of LTE operation in the unlicensed band, namely LTE-U, License Assisted Access (LAA), and MulteFire.

LTE-WLAN aggregation (LWA) is a technology defined by the 3GPP. In LWA, a mobile handset supporting both LTE and Wi-Fi may be configured by the network to utilize both links simultaneously. It provides an alternative method of using LTE in unlicensed spectrum, which unlike LAA/LTE-U can be deployed without hardware changes to the network infrastructure equipment and mobile devices, while providing similar performance to that of LAA. Unlike other methods of using LTE and WLAN simultaneously, LWA allows using both links for a single traffic flow and is generally more efficient, due to coordination at lower protocol stack layers.

References

  1. ↑ Yu, Haoran; Cheung, Man Hon; Iosifidis, George; Gao, Lin; Tassiulas, Leandros; Huang, Jianwei (2017). "Mobile Data Offloading for Green Wireless Networks". IEEE Wireless Communications. 24 (4): 31–37. doi:10.1109/MWC.2017.1600323. S2CID   4440054.
  2. ↑ Perez Sarah (February 11, 2010). "Mobile data traffic surge: 40 exabytes by 2014". Read Write web blog. Archived from the original on August 29, 2011. Retrieved August 25, 2011.
  3. ↑ "Seamless Wi-Fi Offload: A business opportunity today," white paper from Hetting Consulting (Aptilo Networks release)
  4. ↑ Cisco 2021 Forecast Highlights
  5. ↑ Warrior Padmasree, CTO Cisco "Keynote speech in CTIA 2010"
  6. ↑ Cisco Visual Networking Index: Global Mobile Data Traffic Forecast Update, 2009–2014; Cisco 2010
  7. 1 2 Scherzer Shimon "Femtocell vs. Wi-Fi for Data Offloading & Indoor Coverage" Archived 2010-05-23 at the Wayback Machine
  8. ↑ Robb Henshaw "The Role of WiMAX in Enabling Wi-Fi Data Offload Networks"
  9. ↑ Netsnapper
  10. ↑ NokiaSiemensNetworks "Self-Organizing Network (SON) Introducing the Nokia Siemens Networks SON Suite – an efficient, future-proof platform for SON"
  11. ↑ ABI Research "ABI Research Forecasts Wi-Fi Access Point Shipments to Exceed 70 Million by 2010" Archived 2011-07-11 at the Wayback Machine
  12. ↑ "More Than 12 Million AT&T, Starbucks Customers to Get Free Wi-Fi Access for a Rich In-Store Experience". Att.com (Press release). AT&T Intellectual Property. 2008-02-11. Retrieved 2014-07-05. AT&T Inc. (NYSE:T) and Starbucks (NASDAQ:SBUX) today announced plans to deliver AT&T Wi-FiSM service at more than 7,000 company-operated Starbucks locations across the United States.
  13. ↑ X. Kang et al. ``Mobile Data Offloading Through A Third-Party WiFi Access Point: An Operator's Perspective, in IEEE Transactions on Wireless Communications, vol. 13, no. 10, pp. 5340-5351, Oct. 2014.
  14. ↑ J. Cho, et al., SMORE: Software-defined Networking Mobile Offloading Architecture Proc. ACM SIGCOMM AllThingsCellular 2014
  15. ↑ A. Y. Ding, et al., Vision: Augmenting WiFi Offloading with An Open-source Collaborative Platform Proc. ACM MobiCom MCS 2015
  16. ↑ Jouni Korhonen, et al. Toward Network Controlled IP Traffic Offloading IEEE Communications Magazine, Volume 51, Issue 3, p.96 - 102 (2013)
  17. ↑ 3GPP TR 43.902
  18. ↑ 3GPP TS 23.402
  19. ↑ 3GPP TS 23.234
  20. ↑ Aruna Balasubramanian, Ratul Mahajan, Arun Venkataramani. Augmenting Mobile 3G using WiFi Proc. MobiSys 2010
  21. ↑ Kyunghan Lee, Joohyun Lee, Yung Yi, Injong Rhee and Song Chong. Mobile Data Offloading: How Much Can WiFi Deliver? Proc. CoNEXT 2010
  22. ↑ Dimatteo, Savio; Hui, Pan; Han, Bo; Li, Victor O.K. (2011). "Cellular Traffic Offloading through WiFi Networks". 2011 IEEE Eighth International Conference on Mobile Ad-Hoc and Sensor Systems. p. 192. CiteSeerX   10.1.1.378.5023 . doi:10.1109/MASS.2011.26. ISBN   978-1-4577-1345-3. S2CID   16290804.
  23. ↑ A. Krendzel, M. Portolés, J. Mangues, Modeling Network Traffic in Mobile Networks Implementing Offloading, in proceedings of the 14th ACM MSWIM-2011, November 2011, USA
  24. ↑ Aaron Yi Ding, Bo Han, et al. Enabling Energy-Aware Collaborative Mobile Data Offloading for Smartphones Proc. IEEE SECON 2013
  25. ↑ 3GPP TS 23.402
  26. ↑ Paasch, Christoph; Detal, Gregory; Duchene, Fabien; Raiciu, Costin; Bonaventure, Olivier (2012). Exploring mobile/WiFi handover with multipath TCP. ACM SIGCOMM workshop on Cellular Networks (Cellnet'12). p. 31. doi: 10.1145/2342468.2342476 . ISBN   9781450314756.
  27. ↑ Patrick Baier, Frank Dürr and Kurt Rothermel. TOMP: Opportunistic Traffic Offloading Using Movement Predictions Proc. LCN 2012
  28. ↑ Han, Bo; Hui, Pan; Kumar, V.S. Anil; Marathe, Madhav V.; Shao, Jianhua; Srinivasan, Aravind (May 2012). "Mobile data offloading through opportunistic communications and social participation". IEEE Transactions on Mobile Computing. 11 (5): 821. CiteSeerX   10.1.1.224.8056 . doi:10.1109/TMC.2011.101. S2CID   9082268.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.