Published on September 22nd, 2020 | by Dr. Cemal Dikmen
Understanding 5G Standards for Lawful Intercept
5G is the most exciting new technology when it comes to wireless communications. Just like when 4G/LTE enabled many application developments that changed the way we live today, 5G will revolutionize the way we live moving forward. Low-latency and high-speed connectivity will support new and exciting applications and business opportunities. Virtual and augmented reality, self-driving cars and trucks, smart cities and Internet of Things (IoT) are just the beginning. Unfortunately, just like any advancement in technology, the criminal elements will take advantage of these new capabilities for terrorism, drug and human trafficking, cyber-crimes and more. To help catch these criminals, law enforcement will require access to upgraded monitoring capabilities within the 5G networks. To understand what that entails, we need to appreciate how 5G technology has evolved over the last couple of years.
Evolution to 5G
The New Radio (NR) was developed by 3GPP in 2017 for the 5th generation (5G) wireless networks as the air interface. Carriers wanted to take advantage of this technology as quickly as possible. So the standards body 3GPP released an initial version of 5G standards in the 2018. Release 15 for Non-Stand-Alone (NSA) 5G was created to develop 5G specifications as quickly as possible for early 5G NR deployments. 3GPP also developed multiple deployment models where 5G NR interoperated with the 4G Evolved Packet Core (EPC) network. These initial deployment models are referred as Option 3, Option 3a, and Option 3x, and they all leverage the existing 4G EPC for the 5G NR. It allowed carriers to deploy 5G NR using their 4G EPC infrastructure without waiting for the specifications for the 5G core network. These initial deployments occurred around 2019.
As lawful interception takes place in the core network, and the initial 5G NR deployments leveraged the existing 4G EPC network, carriers were able to continue using their existing and compliant lawful interception systems to support their 5G NR deployments. Therefore, Law Enforcement Agencies (LEAs) considered 5G systems as nothing new, just “4G on steroids”. And from a Lawful Interception standpoint, they were right. Those initial systems supported the existing handover specifications such as 3GPP TS 33.106, 33.107 and 33.108 and could only support up to 1Gbps per subscriber bandwidth, since the Evolved Packet Core (EPC) was still 4G and there were capacity limitations on the EPC. Law enforcement agencies had not been required to improve their monitoring centers capabilities in order to handle 5G traffic, with the exception of increasing capacity on their transport and systems to enable the slightly higher throughput.
Current 5G Situation for Carriers & LEAs
Let’s fast forward to 2020. 3GPP developed Stand-Alone (SA) and Non-Stand-Alone (NSA) models that defined specifications for 5G Core (5GC) networks interoperating with both 5G NR and 4G LTE. These were either late Release 15 standards or Release 16 standards. Stand-Alone (SA), also known as Option 2, defined specifications for a pure 5G NR and 5GC network with no 4G interworking. Carriers knew it was going to take a long time to deploy 5G NR for nationwide coverage, and they needed to leverage their 4G cell sites and interoperate with their new 5G networks. Non-Stand-Alone (NSA) architectures such as Option 4, Option 7, 7a and 7x allowed carriers to leverage their 4G LTE radio systems and connect them to the new 5GC network, allowing interoperability between 4G and 5G, and leveraging their existing 4G radio systems for a smooth transition to 5G.
However, both SA (Option 2) and NSA (Option 4, 7. 7a, 7x) take advantage of the new 5GC network, and carriers will need to deploy new lawful interception mediation systems to support the 5G network. 3GPP also created a new set of lawful intercept standards for 5G, namely, 3GPP TS 33.126, 33.127 and 33.128. With these new 5G handover specifications, 5G is no longer “4G on steroids”. Law enforcement agencies will need to upgrade their monitoring centers to support much higher throughputs such as 5Gbps to 10Gbps per subscriber, support the distributed nature of 5G mediation systems, and new handover specifications. (To learn more, check out Managing & Analyzing Huge Datasets)
Adhering to New Specifications
Let’s look at some of the real-life deployment experiences of deploying 5G lawful interception systems. 3GPP Release 16 specifications leverage technologies such as Virtualized Network Functions (VNF) and Containerized Network Functions (CNF) to ensure networks can dynamically scale up and scale down on an on-demand basis. Lawful interception mediation systems must also adopt these new VNF and CNF technologies to dynamically scale up and scale down. In addition, the high-throughput interception demands that multiple Transmission Control Protocol (TCP) connections be used on the handover interface. This requires law enforcement monitoring systems be able to receive intercepted communications over HI2 and HI3 handover interfaces from multiple IP addresses, multiple ports, and multiple TCP connections, which will change dynamically as the network scales. In summary, 5G has revolutionize lawful interception for Law Enforcement Agencies as well as carriers that are deploying true 5G networks. The question is, are they ready for it?
About Dr. Cemal Dikmen
As SS8’s CTO, Cemal plays an integral role in the company’s strategic direction, development, and future growth. A renowned expert and thought leader in the legal compliance and communications analysis domain, he has been a frequent speaker at various industry conferences over the past 10 years. Cemal holds BS, MS, and PhD degrees in Electrical Engineering. You can learn more about Cemal on his LinkedIn profile by clicking here.
About SS8 Networks
SS8 provides Lawful Intelligence platforms. They work closely with leading intelligence agencies, communication providers, law enforcement agencies and standards bodies. Their technology incorporates the methodologies discussed in this blog and the Xcipio® and Intellego® product portfolios are used worldwide for the capture, analysis and delivery of data for the purposes of criminal investigations.