Authentication is one of the corner stones in an offloading solution. Aptilo offers best practice methods as well as alternative solutions, allowing the service provider to mix methods and create more innovative user interfaces.
Authentication methods for offloading
Best practice for offloading – EAP-SIM/AKA
SIM-based authentication is the best practice for authentication for mobile data offloading as it utilizes the same mechanism as in the 3G/LTE network making the authentication process seamless and secure for the end-user. An automatic authentication process in combination with smartphones’ tendency to prioritize Wi-Fi over 3G/LTE connections will ensure a high rate of offloaded users.
The Aptilo SMP SIM Authentication™ authenticates users based on the information retrieved from the HLR or HSS in the mobile core in accordance with the 3GPP AAA functionality.
The Wi-Fi network must support the 802.1x in order to deliver SIM credentials to the SIM authentication function, which provides the additional benefit of encrypting the Wi-Fi link with the same level of security as that which is found in the 3G/LTE network. The security and the automatic authentication process make the Wi-Fi network a trusted extension of the 3G/LTE network. Together with the new IEEE 802.11u standard, SIM-based EAP-SIM/AKA authentication has become the foundation of the next generation hotspot – Hotspot 2.0, as defined by the Hotspot 2.0 Task Group in the Wi-Fi Alliance.
There are about 800 million new Wi-Fi devices activated every year; not all of them will have SIM-cards or support for EAP-SIM/AKA. Mobile operators will need alternative authentication methods to support these customers.
Alternative authentication methods
Aptilo supports a number of authentication methods which can act as alternatives to EAP-SIM/AKA. In real-world deployments service providers always need to balance the security with user experience. These methods can be used to expand and compliment the compatibility of mobile data offloading with legacy devices that do not have SIM cards or support for SIM authentication mechanisms.
Aptilo also allows the service provider to mix authentication methods to create more innovative user interfaces. For example, to SIM-authenticate users automatically before pushing them to a captive portal to approve a daily charge amount or receive a commercial message (“bill chock prevention”).
One-time-password via SMS
Delivering password via SMS to the user or silently to a client application is the best way to securely identify a user on a open SSID Wi-Fi network.
MAC-based authentication
A very common method for Wi-Fi networks running on an open SSID is to use mac-based authentication, were the unique Media Access Control address (MAC) of the device is used for identification. This mechanism provides a seamless user experience with automatic login to the Wi-Fi network and is often used as a re-authentication mechanism for short-term accounts at Wi-Fi hotspots. However, since MAC addresses can be spoofed MAC-based authentication is not commonly used by service providers as the primary authentication mechanism for long-term accounts.
The location-based multi-device login is a patent-pending Aptilo invention which allows mobile operators to achieve a greater level of security for MAC-based authentication of devices in Wi-Fi networks. It makes an automatic MAC-based authentication for multiple devices more secure by tying them to an active mobile phone, belonging to the same subscriber, which is already authenticated via a secure EAP method at the same location.
Aptilo 3GPP Wi-Fi Access Unified
The 3GPP Wi-Fi access standard requires use of SIM authentication (EAP-SIM/AKA) where policies are retrieved from the subscriber profile in the HLR/HSS during the authentication process. These policies are crucial for the Wi-Fi service and include things such as APN and parameters for setting up the individual GTP tunnel for backhauling the user’s traffic to the mobile core.
Aptilo SMP already enables 3GPP Wi-Fi access for mobile phones with SIM cards using EAP-SIM/AKA. Aptilo SMP now extends 3GPP Wi-Fi access support to all Wi-Fi devices including those with SIM cards but lacking support for SIM authentication (EAP-SIM/AKA). This innovation utilizes the highly secure EAP-TTLS/PEAP authentication method instead of EAP-SIM/AKA while retrieving policies from the subscriber profile in HLR/HSS as if it was an EAP-SIM/AKA authentication. The Aptilo SMP retrieve the user’s subscriber profile by using the MSISDN (mobile number) rather than the IMSI (SIM card ID) as an identifier while using EAP-TTLS rather than EAP-SIM/AKA for security (the orange path above). In other words, Aptilo makes 3GPP Wi-Fi access possible in real-world deployments by adding support also for devices lacking SIM authentication capabilities.
The Aptilo 3GPP Wi-Fi access Unified Solution works for any of the 3GPP Wi-Fi access methods. One of the most popular methods is the trusted 3GPP Wi-Fi access. In this method, the user traffic is securely backhauled to the mobile core through a GTP (or MIP/PMIP) tunnel between the WAG/TWAG (Wireless Access Gateway) and the GGSN/P-GW.
