Mobile-to-WiFi roaming promised by WiFi industry bodies


Wireless Broadband Alliance and Wi-Fi Alliance Collaborate on Hotspot Innovations to improve Wi-Fi roaming, data offload and user experience

The Wireless Broadband Alliance (WBA) and the Wi-Fi Alliance have outlined plans to create commons standards that would enable users to connect automatically to WiFi hotspots using SIM-based authentication and security protocols.

The aim is to enable a device to authenticate automatically at a WiFi hotspot, using cellular-based authentication methods such as EAP-SIM/AKA and EAP-TLS/TTLS. This could mean that mobile operators would view WiFi providers as trusted roaming partners, opening up new business relationships and increasing the opportunities for data offload and roaming.

From a useability and business point of view, the implementation of the specifications within devices and access points would enable someone to roam automatically onto a WiFi hotspot for data access, but without having to enter new details, buy credits etc Instead, the device would connect automatically to the hotspot where it sees a network roaming partner it has enabled. The authentication is carried out using access details provided by the mobile operator, who has a back end roaming agreement with the hotspot provider. 

The process uses a protocol called Access Network Query Protocol (ANQP), which will need to be enabled by user devices, as well as access points.

The WBA calls the programme the Next Generation Hotspot (NGH) programme, and it is working with a pilot group of operators and technology providers to define interoperability requirements for hotspot and 3G/4G operators. A trial launched under the program this week between leading operators and vendors will address seamless, secure auto-authentication on multiple operator networks.

The WiFi Alliance, meanwhile, will provide the certification process for NGH-compliant devices and access points.

Stephen Rayment, CTO at Belair Networks, said that the process is about providing secure, seamless roaming.

“Most current hotspots are not secure as cellular networks are secure. There is a call for secure radio links and high performance authentication, using the credentials from the SIM card to authenticate to the WiFi network,” Rayment said.

In Rayment’s view many existing access points will require only a software upgrade, although older infrastructure may need to be swapped. He added that there is a greater need for support from device manufacturers - specifically in implementing ANQP support in devices. The role of the Wi-Fi Alliance is to ensure the user experience is supported in a consistent fashion at the device end. It expects to have its certification process ready by the middle of 2012, with preliminary testing activities expected to begin later this year.

Rayment pointed out that although the NGH programme addresses roaming and sign-on it does not address session mobility – the ability to continue a VPN session between a WiFI hotspot and the cellular network.

“If WiFi is to be part of the 4G family then secure, seamless roaming gets it only 75% of the way there. The other 25% is session mobility. If I have a VPN connection to a mail server and move from the cellular network to WiFi, unless I do something about it then the IP address will change and the session will drop. We are working to solve that by demonstrating proxy mobile IP, connecting the access point to a home agent in the core.”