The number of wireless subscribers accessing mobile data services continues to increase. Third Generation, or 3G, has been adopted and gained traction rapidly due to a variety of developments, including the: • Wide-spread availability of mobile broadband services using USB modems and data cards at affordable prices • Increasing penetration of 3G-enabled smartphones such as the iPhone, BlackBerry phones and Android phones • Plethora of smartphone applications • Flat rate plans • Widespread deployment and coverage of 3G data networks These developments will continue to drive the increase of mobile data traffic volume. However, they could also create challenges for 3G operators in supporting traffic growth, particularly when licensed spectrum is limited. In order to cope with this traffic growth, operators can use traditional mechanisms to expand network capacity. But these often entail high cost investments. Since data service value is detached from the traffic volume, it creates pressure on the deployment costs. The operator challenge is in developing pricing models that maximize revenue per MB and deploying networks that minimize cost per MB. In this environment, intelligent resource management provides a cost-effective way to support the data traffic growth by optimizing network use, balancing the network load, lowering network congestion, and delaying CAPEX investments. Since WLAN is widely available at home and various hotspots, and is also in a number of 3G devices, a mechanism that offloads data traffic from 3G to Wi-Fi is very compelling to operators that want to minimize data costs and make better use of their assets.
Flat Rate plansDemand for data keeps on increasing. In 2014 you would need each sector to serve 48Mbps. This would mean multiple base station deployments and more significantly more spectrumData service value detached from Traffic volumeCan’t use traditional methods of expansion
Femtocell is a viable approach as long as service providers subsidize it and they are ready to handle the operational challenges of deploying and supporting them.Local IP Access (LIPA): LIPA provides access to a residential/corporate local network interconnected to a femtocell (Home (e)NodeB Subsystem). Primary motivation is to provide access to a subnet within home or an office for shared resources like printers, file servers, media servers, displays, etc. while amobile device is attached to the 3GPP operator network. LIPA capability will be introduced with 3GPP Release 10 specifications.• Selected IP Traffic Offload (SIPTO): SIPTO refers to the ability to selectively forward different types of traffic via alternative routes to/from the terminal device. Home network flavor of SIPTO is dependent on using a Home (e)NodeB. In this mode, specific traffic determined by operator policy and/or subscription transferred to/from (e)NodeB directly to Internet/Intranet bypassing the mobile operator access/core network. Macro network flavor of SIPTO covers the ability to offload traffic next to an Radio Network Controller (RNC) for 3G or Serving Gateway (S-GW) for LTE as opposed to traversing the operator's core network.
– Home Networks, Hotspots, 3G/4G Devices all support Wi-Fi and so it is obvious that Wi-Fi would become an extension of 3G/4G networksWi-Fi offloading has been explored since a long time.
Offload data from 3G to Wi-FiNo IP preservation after switchingHeavy reliance on App to preserve state after switchingBad performance of VPN, HTTPS, Streaming video
Introduction of DSMIPIP Address preservationNo special support from WLAN requiredEither on IPv4 or IPv6Home Agent makes the bindingsNo granular flow control
Seamless handover for selected trafficSimultaneous use of both 3G/4G and WLANTraffic has to be anchored in HALike all IP address preservation mechanisms, IP Flow Mobility requires the traffic to be anchored in a central gateway (e.g., HA). Therefore, the 3G/Wi-Fi Seamless Offload traffic has to pass through the HA whenever mobility and session continuity are required. In order to use network resources in the most efficient way, the proper approach is having a mix of traffic anchored at the HA for mobility purpose (i.e., VPN, Video) and some traffic completely offloaded to WLAN without traversing the HA (i.e., HTTP).
Policy is preference list of access UE should use at a particular date and timeIntroduced in Release 8, Policy is determined by ANDSF – Access Network Discovery and Selection FunctionBased on communication between handset and OMA-DM ServerIFOM extends policy by introducing Traffic type criteriaIF no Device Management server can be found than use the local handset UE policy
What is IFOM and seamless Wi-Fi offloading?
Current Scenario and shortcomings Why the need for different offloading solutions? What is IFOM and Seamless WLAN offload
Need heavy subsidy from SP High Operational costs Offloading relies on changes upstream to route traffic Two Standards for offloading ◦ LIPA ◦ SIPTO
Wi-Fi is ubiquitous Currently 40% content delivered to smartphones over Wi- Fi 3.5 Billion WiFi devices by 2014 - Instat 802.11N adds significant capacity changes Doesn’t depend on RAN nodes for routing Can be applied to legacy and new technologies
Source: Qualcomm Network discovery and selection policy is determined by ANDSF Based on communication between handset and OMA-DM Server IFOM extends policy by introducing Traffic type validation criteria
Source: Qualcomm UE is the best positioned to decide its connectivity options Connection manager in the device makes this decision Search and Prioritization based on: ◦ QoS ◦ Bandwidth, Jitter, Latency ◦ Power consumption, Operator policies etc.