Lawful interception (LI) functionality refers to the legally approved surveillance of telecommunication services. It has become an important tool for law enforcement and intelligence agencies around the world for investigating and prosecuting criminal activities and terrorist operations.
Most countries have passed laws requiring telecommunication service providers to assist law enforcement agencies (LEAs) with duly authorized requests to identify, monitor, and deliver electronic communication of individuals. There are also national regulatory authorities and international standardization bodies that together define the technical framework for legal interception.
Yesterday, the U.S. Patent and Trademark Office officially granted Apple a patent that relates to Lawful Intercept (LI) services for iPhones and other mobile communication devices such as Apple Watch, MacBooks and iPad.
Described techniques in Apple’s granted patent may enable Lawful Intercept (LI) services for iPhones in situations where at least one iPhone is participating in Proximity Services (ProSe) such that the iPhone (User Equipment – UE) is “indirectly” coupled to a cellular network via a relay device.
As an example of this situation, a group of public safety personnel (e.g., firefighters) may be first responders at an accident. UEs of one or more members of the group may be out of the coverage range of the cellular network used by the group (e.g., some of the members may be indoors, in a tunnel, etc.). The members of the group may continue to communicate with one another and with the cellular network using ProSe communications services.
In this scenario, the UE of one member of the group, which may be within the coverage range of the cellular network, may act as a relay device for other members of the group, which may be referred to as “remote UEs” that are out of the coverage range. All members of the group may, in this way, continue to communicate via the cellular network. This is essential in times of emergency.
In some situations, such as in the case of Internet Protocol (IP) version 4 addressing (IPv4), the UE acting as the relay device may use Network Address Translation (NAT) techniques when relaying traffic. NAT may obscure visibility, from the standpoint of the cellular network, about which traffic flows correspond to the relay UE and which traffic flows correspond to the remote UEs. This can be problematic for the performance of lawful intercept services.
Consistent with aspects described in Apple’s granted patent, the relay device may assist in enabling lawful intercept by reporting, to a LI device associated with the cellular network, authenticated identities of the remote UEs and identification information that may allow the LI device to monitor traffic (and/or control statistics related to the traffic) associated with the remote UEs.
In the context of public safety services, ProSe communications can provide an important fallback public safety network that may function when a cellular network (e.g., a 3GPP cellular network) has failed or is unavailable.
Public safety application server #130 of FIG. 1 below may include one or more computation and communication devices that provide services to public safety personnel and/or organizations. For example, public safety application server may provide services relating to ProSe communications between public safety personnel, such as services relating to assisting in the identification of UEs in physical proximity with one another and/or the enablement of optimized communications between the UEs.
As another example, the public safety application server may function to enable group calling between groups of public safety personnel, such as one-to-many calling or the dispatching of public safety personnel to emergency situations.
Although shown as being implemented outside of wireless network #120, in practice, public safety application server may alternatively or additionally be implemented within wireless network.
During 9/11 many first responders were unable to communication with commanders and missed important flashpoints that could have saved lives. Since that time various governmental Agencies came up with communication standards working with networks and device makers. Below is a video snippet from Dereck Orr, Chief Public Safety Communications Research (PSCR) Division of NIST.
Apple’s granted patent covers specific communication systems for an iPhone to access the Public Safety Application Server and to be in compliance with standards related to Law Enforcement Agencies (LEAs).
For more on this, especially for wireless engineers, read Apple’s full granted patent 11,394,454.
