In a world where everything from cars to coffee machines is connected through the Internet of Things (IoT), securing next-generation 5G networks is more important than ever. IoT links devices to the internet, creating endless opportunities—and vulnerabilities. SABRES is a project by USC’s Information Sciences Institute (ISI) and DARPA’s Open, Programmable, Secure 5G (OPS-5G) program, which aims to secure 5G networks and prepare for future technologies like 6G. Led by ISI’s Erik Kline, SABRES is redefining network slicing, a technology central to 5G, to make it faster, safer, and scalable.

What is SABRES?

SABRES—short for "Secure, Adaptive, roBust, Resilient, and Efficient Slices"—aims to address four key challenges in modern networking: efficiently allocating resources across vast networks, verifying the integrity of those resources, protecting data in transit, and mitigating risks associated with shared infrastructure.

At the heart of SABRES is a unique mathematical approach called conflict-based search (CBS). This method optimizes the allocation of virtual network slices, or segments of a physical network that are reserved for specific uses. Unlike traditional methods, which either scale poorly or compromise efficiency, CBS separates simple and complex parts of the problem, solving them individually. This not only accelerates calculations but also ensures better use of limited resources.

“We’ve really done something novel here,” said Kline, a Principal Scientist in the Networking and Cybersecurity Division at ISI. “We developed an algorithmic framework for the virtual network embedding problem that combines state-of-the-art efficiency with real-world scalability. That’s not easy to achieve in this field.”

SABRES improves upon existing methods by addressing network slices in parts: solving straightforward sections quickly and focusing computational power on more complex conflicts.

How SABRES Tackles the Challenges of 5G

1. Efficient Resource Allocation: Using CBS, SABRES calculates and embeds network slices efficiently while meeting constraints like bandwidth, latency, and security. This approach ensures that even large-scale networks remain manageable. “The embedding process is really tricky. You’re mapping virtual resources onto physical ones while respecting constraints like capacity and latency,” Kline explained. “The CBS method lets us optimize these mappings in a way that works across different scales”​.
   
   
2. Verification: SABRES verifies that allocated resources meet specified requirements. For instance, proof-of-work tests ensure nodes meet computational needs without leaking sensitive information. “It’s not enough to allocate resources—you have to make sure they’re doing what you expect them to, and that you can prove it,” said Kline​.
   
   
3. Obfuscation and Security: To protect sensitive communications, SABRES employs obfuscation techniques that prevent traffic patterns from revealing usage details. “Traffic analysis attacks are a real threat. Just because your data is encrypted doesn’t mean someone can’t infer something from how it flows,” Kline noted. “We use obfuscation to close those gaps.”​
   
   
4. Cross-Network Scalability: SABRES enables secure communication across networks, a notoriously difficult problem in telecommunications. “Interoperability across different networks is incredibly hard,” Kline said. “We’ve tailored the CBS approach to handle the complexities of working across domains, and we can do it in a trusted fashion.”​

Real-World Applications

The work done by SABRES has wide-ranging implications. In a commercial setting, the principles of network slicing can create bespoke experiences, such as augmented reality at live stadium events. In more critical applications, such as defense, it enables secure, scalable communication between service members in remote locations and central command.

“In defense applications, it’s not just about connecting Point A to Point B,” Kline explains. “It’s about doing so securely, ensuring that sensitive data isn’t leaked or compromised, even if the infrastructure involves untrusted third parties.”

The Team Looks to the Future

As the SABRES project nears completion, the team is focused on transitioning its breakthroughs to the broader community. Technologies developed as part of SABRES are already finding applications in related fields, from data center optimization to enhanced cybersecurity protocols. The SABRES team includes collaborators from telecommunications giant Lumen Technologies and cryptography specialists Duality Technologies. These partners bring unique expertise, helping SABRES transition its innovations into real-world applications. 

In the larger scope of DARPA’s OPS-5G program, SABRES exemplifies the initiative’s goals: fostering innovation while addressing the unique security challenges of modern networks. “SABRES is about more than solving a mathematical problem,” Kline emphasizes. “It’s about ensuring that the networks we rely on are safe, scalable, and adaptable to the challenges of tomorrow.”