Integrating Cellular and Wi-Fi Critical to Meeting Capacity Demands

4G Americas Report Recommends Convergent Solutions for Mobile Broadband Access


BELLEVUE, WA--(Marketwired - Sep 26, 2013) - "Resources of existing cellular networks are becoming increasingly constrained with smartphone adoption and bandwidth intensive services such as streaming video," remarked Chris Pearson, President of 4G Americas. "The Wi-Fi technology standard is uniquely positioned to complement existing cellular networks given its wide adoption and harmonized unlicensed global spectrum allocation. However, to provide an enhanced customer experience, service providers need to improve Wi-Fi and Cellular interworking for ubiquitous mobile broadband access."

4G Americas, a wireless industry trade association representing the 3GPP family of technologies, including LTE, today announced that it has published a white paper, Integration of Cellular and Wi-Fi Networks, which explores the current state of Wi-Fi/Cellular integration and makes specific recommendations to enhance key components: Wi-Fi network selection and traffic steering, referred to as Intelligent Network Selection (INS). The paper reviews and describes fundamental aspects to Wi-Fi such as:

  • Seamless service / session continuity, QoS, security, Hotspot 2.0 and concepts of Intelligent Network Selection (INS)
  • Access Network Discovery and Selection Function (ANDSF), its technical background and existing challenges for ANDSF-based INS
  • Device aspects of network selection and traffic steering, current standards and solutions and gaps in existing standards work

The white paper reviews the standardization work in 3GPP for a network-based mobility mechanism (SaMOG). This technology option supports tight integration of Trusted Wi-Fi networks with 3GPP Cellular networks and is identified as the best path forward. Subscribers can move between LTE and Trusted Wi-Fi networks while preserving their IP address and allowing access to Operator Services over Wi-Fi (e.g., IP Multimedia Subsystem or IMS). The paper also explores how to enable real-time services and end-to-end Quality of Service over an integrated Trusted Wi-Fi network. The paper recommends the use of the WPA2 airlink encryption and SIM-based credentials for authentication purposes by dual mode devices that support both Wi-Fi and Cellular accesses.

The main focus for the paper is Intelligent Network Selection (INS) which is enabled by Access Network Discovery and Selection Function (ANDSF). Defined in 3GPP as a framework for carriers, INS distributes operator-defined policies to devices in order to guide network selection and traffic routing decisions between Wi-Fi and Cellular networks. Using ANDSF for Wi-Fi network selection can contribute to better network performance and lead to improved user experience.

"Wi-Fi is an important unlicensed spectrum technology for most operators and the intelligent integration of Wi-Fi and Cellular will provide a benefit to both operators and their customers," stated Farooq Bari of AT&T and co-project leader of the 4G Americas technical group that authored the white paper.

Gautam Talagery of Ericsson, another co-project leader stated, "Wi-Fi is one of the tools in the toolkit for operators to meet the increasing demand for mobile broadband connectivity, especially indoors, and to help mitigate resulting network capacity concerns." 

Key recommendations in the white paper include:

For standards bodies: enhancement of existing ANDSF solution by standardizing additional interfaces and operator policies and enabling the use of real-time Wi-Fi and Cellular load related conditions

For device-side suppliers: implementation of standardized INS mechanisms (e.g., ANDSF functionality) and enhancements, such that INS behavior is consistent across device platforms

For network infrastructure suppliers: implementation of proposed enhancements in support of ANDSF-based INS (e.g., new SIB mechanism and ANDSF interfaces)

The white paper, Integration of Cellular and Wi-Fi Networks, was written collaboratively by members of 4G Americas and is available for free download at: www.4gamericas.org.

About 4G Americas: Unifying the Americas through Mobile Broadband Technology
4G Americas is an industry trade organization composed of leading telecommunications service providers and manufacturers. The organization's mission is to promote, facilitate and advocate for the deployment and adoption of the 3GPP family of technologies throughout the Americas. 4G Americas contributes to the successful commercial rollout of 3GPP mobile broadband technologies across the Americas and their place as the No. 1 technology family in the region. The organization aims to develop the expansive wireless ecosystem of networks, devices, and applications enabled by GSM and its evolution to LTE. 4G Americas is headquartered in Bellevue, Wash., with an office for Latin America and the Caribbean in Dallas. More information is available at www.4gamericas.org.

4G Americas' Board of Governors members include: Alcatel-Lucent, América Móvil, AT&T, BlackBerry, Cable & Wireless, CommScope, Entel, Ericsson, Gemalto, HP, Mavenir, Nokia Solutions and Networks, Openwave Mobility, Powerwave, Qualcomm, Rogers, T-Mobile USA and Telefónica.