Cutting roaming costs and expanding coverage with Radiator SIM-based authentication.

Modern SIM-based devices, like smartphones and tablets, are able to join and switch between different networks automatically. This is especially valuable to mobile operators who want to offload data from their mobile network to a nearby Wi-Fi network, because Wi-Fi connections are significantly cheaper to operate. It also enables Wi-Fi providers to monetize their Wi-Fi net- works and provide services in partnership with mobile operators. In addition, with use of OpenRoaming or other Wi-Fi roaming services, it also provides a way to expand the coverage of carrier Wi-Fi.

Use cases for the SIM authentication include:

Wi-Fi Offloading:

In busy locations with high volumes of mobile traffic like sports stadiums, shopping malls, public transport hubs and underground metros, SIM-based devices can automatically switch from mobile data connections to local Wi-Fi networks. Transferring the data traffic to Wi-Fi networks reduces the load on the mobile network, which improves the coverage and the user experience. In addition, using Wi-Fi roaming services, such as Orion Wi-Fi or OpenRoaming, can further reduce costs when carriers can use these additional services for Wi-Fi offloading.

Voice over Wi-Fi

SIM-based devices can also switch voice calls from mobile networks to Wi-Fi networks, and this kind of call is known as Voice over Wi-Fi. As with data traffic, switching traffic from regular calls to Wi-Fi networks can help carriers and operators to reduce the load on the mobile network, enabling better call quality and continuity.

Wi-Fi Roaming

When a SIM-based device automatically joins a Wi-Fi network or switches to another one, this is called Wi-Fi roaming. Wi-Fi roaming is used to maintain an uninterrupted data connection when the user moves from location to location, or when the current Wi-Fi connection is overloaded or when the signal is weak. In these situations as well, using OpenRoaming and other Wi-Fi roaming services can expand the coverage for mobile carrier.

Wi-Fi SIM-based authentication is essential to making these capabilities work. Before a device is allowed to join a new Wi-Fi network, it must be authenticated using the IMSI*. For this reason, Wi-Fi SIM-based authentication is supported by the latest Android and iOS mobile devices. However, there are still some security issues with this type of authentication. As a result, mobile OS manufacturers are now pushing for even better security on Wi-Fi networks and they require IMSI Privacy Protection with all new OS versions.

How can Radiator help you in this?

The Radiator SIM Pack for Radiator AAA Server Software makes it easy for operators to enable IMSI Privacy Protection. It is the key component needed for secure and seamless switching between mobile and Wi-Fi networks using SIM-based authentication. The Radiator SIM Pack also provides all the functions required for a 3GPP AAA Server.

IMSI privacy is a key feature of the Radiator SIM Pack, and it provides server-side support for permanent identity protection during Wi-Fi SIM-based authentication, Wi-Fi offloading and VoWiFi, resulting in a higher quality user experience. You can read more about Radiator SIM Pack and IMSI Privacy protection from our IMSI Privacy whitepaper.

In addition to this, Radiator provides also all the services and products needed when joining to  Wi-Fi roaming services, such as OpenRoaming, or when connecting to mobile carrier infrastructure by using Diameter interfaces.

Would you like to know more?

If you would like to know more about Radiator, SIM authentication, IMSI Privacy, joining OpenRoaming etc., and how we can help you in your use case, you can always contact our team at info(a)radiatorsoftware.com. Looking forward to hearing from you!

*) In SIM-based mobile devices, like smart phones and tablets, the user’s unique identifier is stored on the SIM card in a standard format known as the International Mobile Subscriber Identifier, or IMSI for short.

Radiator provides IMSI privacy for EAP-SIM, EAP-AKA and EAP-AKA’ authentication

In many high traffic areas such as sports stadiums, shopping venues, or public transport hubs, mobile carriers may partner with the local Wi-Fi providers to improve coverage and user experience: mobile devices can be automatically connected to Wi-Fi instead of congested cellular network. Internationally, Wi-Fi roaming agreements also allow carriers to lower the cellular roaming costs. 

EAP-SIM, EAP-AKA and EAP-AKA’ are SIM-based Wi-Fi authentication methods used to achieve seamless offloading to carrier and partner Wi-Fi, with International Mobile Subscriber Identifier (IMSI) derived from the SIM card acting as a unique identifier for each user. 

On the first ever connection to such a Wi-Fi network, the mobile device communicates its permanent subscriber identity information (IMSI), which is then sent to the home operator for authentication. This identity is sent in the clear. A potential 3rd party adversary installing a Wi-Fi sniffer in the vicinity of such networks can harvest permanent identities and track users. This tracking can also be done by the venue or network owner when connecting to the Wi-Fi network. 

Because of this, mobile operating systems such as iOS15 will show the following warning when joining a Wi-Fi network without IMSI encryption: “your mobile subscriber identity will be exposed”. The similar situation can be seen from the pictures below. 

Privacy warning when authenticating to Wi-Fi network without IMSI encryption

 

Operators risk decreased user satisfaction for Wi-Fi offloading if transmitting IMSI in the open - it may cause users to feel their privacy is being compromised.

Radiator SIM Pack provides IMSI privacy protection 

The solution is to protect user privacy by implementing IMSI encryption for EAP-SIM, EAP-AKA and EAP-AKA’ authentication. As an operator, you can enable IMSI privacy easily: Radiator 3GPP AAA Server handles both encrypted and clear authentication requests. This means IMSI privacy can be offered to devices supporting it without affecting other users. 

Starting already from revision 2.5, Radiator SIM Pack supports IMSI encryption as specified in 3GPP S3-170116 document “Privacy Protection for EAP-AKA” (zip), and WBA’s IMSI Privacy Protection for Wi-Fi – Technical Specification. The feature is already implemented by some of our operator customers to cover their AAA server encryption. 

The latest release of Radiator SIM Pack is available for new licensees and for licensed customers with valid download access. To find out if Radiator SIM Pack suits your needs, you can contact us at sales@radiatorsoftware.com and a member of our sales team will be happy to assist you. 

You can also contact us to renew your support contract and get access to the newest release. A full history of Radiator SIM Pack releases is available on our website.

Protecting user identity with Radiator SIM Pack

Nowadays, mobile operators use complementary network technologies to improve user connectivity. Mobile data traffic originally targeted for cellular networks can be offloaded to designated Wi-Fi hotspots, therefore relieving congestion in high traffic areas. By implementing SIM authentication with Radiator SIM Pack, customer experience is enhanced by seamlessly authenticating users and logging them into the Wi-Fi network.

Cellular networks use IMSI (International Mobile Subscriber Identity) as a unique identifier for every user of the network, which comprises 15 digits including the user's telephone number. When this identifier is sent by the device to the network, privacy can be compromised if the connection request is not encrypted. This encryption relies both on the operator's AAA server and the user device.

Starting from revision 2.5, Radiator SIM Pack supports IMSI encryption, also known as "Permanent Identity Encryption"; functionality specified in 3GPP document S3-170116: "Privacy Protection for EAP-AKA". This feature is already implemented by some of our operator customers to cover their AAA server encryption. Alongside device manufacturers such as Apple, who already implement identity encryption, permanent identity of the user is not exposed, increasing their privacy protection.

The latest release of Radiator SIM Pack is available for new licensees and for licenced customers with valid download access. To find out if Radiator SIM Pack suits your needs, you can contact us at sales@radiatorsoftware.com and a member of our sales team will be happy to assist you. You can also contact us to renew your support contract and get access to the newest release. A full history of Radiator SIM Pack releases is available on our website.

Radiator 3GPP AAA Server white paper published

We are happy to announce that Radiator 3GPP AAA Server white paper (pdf) has now been published. 3GPP AAA Server white paper, as well as our previous white papers about Radiator SIM support and Radiator Policy and Charging support, can be found from OSC website.

If you are in a need for 3GPP AAA Server solution, you can always contact us at sales(a.t.)radiatorsoftware.com

Using Radiator for Wi-Fi offloading: how to make savings in mobile packet core network

With Wi-Fi offloading, mobile operators can transfer traffic from their Evolved Packet Core network to Wi-Fi networks. One of the key reasons for this is cost savings - as an example from Radiator customer can demonstrate.Our customer has currently 50,000 public hotspots in their country - the best Wi-Fi coverage in the nation.

Hotspots in the country by operator

In order to get the most out of their Wi-Fi network, a solution was needed for automatic SIM authentication for mobile users. For this, our regional partner implemented a solution with Radiator SIM Pack for the customer. This enabled them to increase the network usage from 1 M usages  per month to over 70 million usages per month. A key component, in addition to Radiator SIM Pack, was iPhone Carrier Bundle with auto connect - that provides automatic authentication to the end-user.

After the initial surge, customer still sees growth of 13 % per month.

The current progress of WiFi Auto Connect usage

Because of the solution, customer is now offloading almost 600 TBytes of data from evolved mobile packet core (EPC) each month - and the amount is still growing. If cost of each GByte to the EPC is around USD $4, the customer is saving over USD $2M per month - and over $24M per year!

Amount of offloaded data by month

Interested in Wi-Fi offloading?

If you have interest in Radiator solutions for Wi-Fi offloading - please do not hesitate to contact our sales team at info@open.com.au