Regulators have required geographic redundancy for the network resources operated by communication service providers (CSPs) for some time but meeting this mandate has become more complex with recent changes to network topologies. Traditional, centralized networks were designed to failover to an alternate, geographically distant data center if a natural disaster or other event caused a site outage or the loss of connectivity to a site. In practice, such failures are rare and disaster-recovery plans were mostly invoked for testing and drills, so it became acceptable for failover processes to require manual human intervention.
Today’s communications networks, with tens of thousands of elements including public and private cloud resources, make this significantly more difficult. The architecture’s complexity greatly expands the number of potential failure points and the likelihood of a failover. Yet because the first thing people often do in an emergency is get on their phone, CSPs strive for failover to occur without service interruption or packet loss, meaning up to five nines (99.999%) availability. In that context, responses to system failures must be automatic and nearly instantaneous, far faster than possible with humans in the control loop.
In most jurisdictions, CSPs are mandated to provide the same standard of service for lawful interception as they provide to customers, so a failover cannot result in the loss of lawfully intercepted data. Therefore, high network availability must extend fully to lawful intelligence functions such as the Administrative Function (ADMF), which manages the administration of a warrant and other legal authorization and the provisioning of network elements for targeted interception. SS8 is contributing significant resources and expertise to the development of functionalities, best practices, and international standards that advance the state of geographic redundancy in lawful intelligence operations.
Shifting Requirements in Modern Networks
The most dramatic evolution from one network generation to the next is typically data throughput—from kilobit speeds in 3G to megabits in 4G and gigabits in 5G. The massive data sets involved in today’s communications require network elements to be moved closer to the subscriber to avoid overwhelming backhaul expenses. The need to switch traffic far from the network core has created massive growth in edge processing capabilities and dramatically increased the complexity of the associated requirements for network infrastructure.
Twenty years ago, the number of network elements in a nationwide network like the United States’ might have been 200 or so mobile switching centers. By contrast, today’s systems may connect to tens of thousands of network elements, making manual operations untenable.
Without automation, that failure rate would require massive staff resources and interfere with both customer services and lawful interception. As such, redundancy expectations are becoming more demanding. In the past, CSPs generally maintained 1+1 redundancy, where every network resource had a corresponding backup resource on standby at a remote location. The current trend is N+K architecture, where K spare resources are maintained for a set of N primary resources. Here, N is ideally larger than one and K is always larger than one, providing a minimum of one active and two standby systems or preferably, two active and two standby systems.
Evolving Lawful Interception Standards and Practices
The past several years has seen a significant strengthening of 3GPP and ETSI standards for lawful interception. Previous iterations of the standards tended to be relatively vague and non-prescriptive. With the development of 5G, those standards have begun to specify key elements of lawful interception more closely, including elements needed to support non-service-impacting failover.
Previously, the absence of such specificity meant that service and equipment vendors implemented proprietary failover mechanisms. That lack of standardization reduced interoperation with technologies from other vendors, and particularly impacted automation among those elements. Therefore, manual intervention was typically needed for failover, which could easily impact service and lead to lost packets, lost communications, and lost events. Recent work by standards bodies has added mechanisms and tools to help CSPs implement interoperable network elements that automate failover and improve geo-redundancy to ensure uninterrupted service.
SS8 is working to develop and advance these standards, drawing on more than two decades of leadership in lawful and location intelligence to help guide the industry forward. We are already implementing N+K architecture on ADMFs as well as the MDF2 and MDF3 mediation and delivery functions of our lawful intelligence platform. These steps and others, many of which are not yet required by standards or government mandates, help assure law enforcement investigations can continue unhindered, without a packet lost, even in the event of a major outage or natural disaster.
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
As a leader in Lawful and Location Intelligence, SS8 helps make societies safer. Our commitment is to extract, analyze, and visualize the critical intelligence that gives law enforcement, intelligence agencies, and emergency services the real-time insights that help save lives. Our high performance, flexible, and future-proof solutions also enable mobile network operators to achieve regulatory compliance with minimum disruption, time, and cost. SS8 is trusted by the largest government agencies, communications providers, and systems integrators globally.
Intellego® XT monitoring and data analytics portfolio is optimized for Law Enforcement Agencies to capture, analyze, and visualize complex data sets for real-time investigative intelligence.
LocationWise delivers the highest audited network location accuracy worldwide, providing active and passive location intelligence for emergency services, law enforcement, and mobile network operators.
Xcipio® mediation platform meets the demands of lawful intercept in any network type and provides the ability to transcode (convert) between lawful intercept handover versions and standard families.
To learn more, contact us at info@ss8.com.
