MAT Working Group Minutes - RIPE 90
Date: Tuesday, 13 May 16:00 - 17:30 (UTC+1)
Working Group Chairs: Massimo Candela, Nina Bargisen, Stephen Strowes
Scribe: Anastasiya Pak
Status: Draft
Welcome
Working Group Chairs
The presentation slides are available at:
https://ripe90.ripe.net/wp-content/uploads/presentations/75-ripe90-mat-wg-open.pdf
Stephen Strowes opened the session by welcoming attendees and introducing the co-chairs Nina Bargisen and Massimo Candela. He reviewed the purpose of the MAT Working Group - to bridge the gap between academic research and network operations, bring in new participants, and foster an environment for sharing data-centric studies.He presented a self-assessment of the MAT WG over the last six meetings, highlighting submission demographics, peer-review metrics, and speaker diversity. Notably, about 50% of presenters were first-time attendees, and approximately 60% of submissions were accepted, indicating a healthy selection process. The talk rating statistics suggested that sessions are well received, with average scores hovering between 4-5.
Lost in Encryption: Monitoring Audio and Video Flows without Payload in Video-Conferencing Applications
Julien Gamba, Cisco ThousandEyes
The presentation slides are available at:
https://ripe90.ripe.net/presentations/32-mat_media_flows.pdf
Julien Gamba discussed the monitoring of audio and video flows in video-conferencing applications. He introduced a methodology for monitoring video-conferencing applications, inferring media metrics such as video resolution and frame rate based solely on a 5-tuple and packet timing without access to packet payloads or RTP headers. Julien showed how monitoring from the client side using lightweight techniques could reveal useful media flow information with over 99% accuracy. The detection and monitoring happen completely on the client side with a minimal impact on battery life.
Daniel Karrenberg, RIPE NCC, suggested that a matrix, mapping what types of traffic features (CDF, sizes, etc.), lead to which inferences would enhance clarity. Julien appreciated the idea.
Sergey Gorinsky, IMDEA Networks Institute, asked how video and screen sharing traffic are differentiated. Julien responded that packet size distribution is key: screen sharing appears similar to video but with lower frame rates and slightly smaller average packet sizes. He added that differentiating the two is still under active investigation.
Geoff Huston, APNIC, noted the absence of packet sizes above 1280 bytes in Julien's dataset. Julien confirmed that outliers toward 1470 bytes were rare in his observations.
WhoActuallyIs? Finding the Companies Behind the Networks
Joshua Levett, University of York
The presentation slides are available at:
https://ripe90.ripe.net/wp-content/uploads/presentations/61-WHOactuallyIS-RIPE-90.pdf
Joshua presented a research tool designed to resolve ownership and operational affiliations between network resources more accurately. His tool aggregates information from RDAP, Whois, DNS, PeeringDB, and registries using natural language processing and entity matching. The system can distinguish between legal operators and customers and trace acquisitions, such as Akamai's purchase of Linode, as an example.
Geoff Huston, APNIC, highlighted the utility of org IDs in RIR extended stats files, which help associate multiple resource types (IPv4, IPv6, ASNs) with a single entity. Joshua noted they were using these IDs and acknowledged the challenge of consistency across RIRs.
Nina Bargisen, MAT WG Co-Chair, asked what could help researchers like Joshua. He replied that updating registry information during mergers/acquisitions would greatly improve data accuracy, particularly when contact information and entity names align post-acquisition.
Pontus: A Memory-Efficient and High-Accuracy Approach for Persistence-Based Item Lookup in High-Velocity Data Streams
Weihe Li, University of Edinburgh
The presentation slides are available at:
https://ripe90.ripe.net/wp-content/uploads/presentations/51-pontus.pdf
Weihe introduced “Pontus,” a high-speed sketching technique for identifying persistent items in high-velocity network data. Pontus improves on prior approaches by introducing a new decay mechanism and optimising memory usage for L1 cache environments. He demonstrated strong detection performance using real traffic traces and noted successful deployment on Tofino switches.
Stephen Strowes, MAT WG Co-Chair, asked about further accuracy improvements. Weihe mentioned that using more compact data types or bit-level counters could increase memory efficiency and detection rates, especially under skewed traffic distributions.
No further questions were raised.
Frontiers of LEO Space Networks: Understanding the Intricacies of Starlink's Internet Access
Nitinder Mohan, TU Delft
The presentation slides are available at:
https://ripe90.ripe.net/wp-content/uploads/presentations/20-ripe-final_min.pdf
Nitinder explored the evolving landscape of LEO satellite Internet, focusing on Starlink as a representative. His measurements from RIPE Atlas, MLab, and browser-based tools showed that while Starlink provides low-latency access in regions with strong infrastructure (US, EU), other regions (e.g., parts of Africa and SE Asia) experience indirect routing and higher latencies.
He demonstrated how Starlink's ground infrastructure layout, not the satellite paths themselves, dictated most latency behavior. For instance, in the Philippines, improved performance was observed only after the introduction of a local PoP in 2023.
Blake Willis, speaking for themselves, and others paid tribute to the late Dave Täht, who significantly contributed to bufferbloat mitigation in Starlink’s QoS implementation.
Nitinder added that Starlink is not widely sharing any details and he started this research thanks to Dave’s support.
Dmytro Kohmanyuk, Hostmaster LLC, asked if the team tested IPv6 vs. IPv4 performance and whether it was possible to identify the specific ground stations or satellites involved in user connections. Nitinder explained that Starlink IPv4 connections are entirely hidden behind Carrier-Grade NAT, offering no visibility into the satellite or ground station path in traceroutes or diagnostic tools. In contrast, IPv6 offers slightly better transparency, making it possible to observe the path to the ground station, though not beyond. The satellites themselves remain invisible in both protocols, as they do not respond to probes or appear in hop traces.
Hardware-assisted Virtual Networking for Low-latency Network Services
Florian Wiedner, TU Munich
The presentation slides are available at:
https://ripe90.ripe.net/wp-content/uploads/presentations/3-slides.pdf
Florian presented results from years of research on achieving sub-millisecond latency in virtualised environments using Linux containers and VMs. His experiments with real-time kernels, CPU pinning, and DPDK showed that careful system tuning can bring container-based latencies on par with bare-metal.
Nina Bargisen asked what operators should consider when applying these optimisations. Florian pointed to his published guides and recommended container-level tuning with real-time kernels and disabled power-saving features for best results.
RIPE NCC Tools Update
Robert Kisteleki, RIPE NCC
The presentation slides are available at:
https://ripe90.ripe.net/wp-content/uploads/presentations/46-RIPE90-MAT-NCC-IMT.pdf
Robert gave an update on the RIPE NCC’s measurement tools: RIPEstat, RIS, and RIPE Atlas. The new UI for RIPEstat has launched and a refreshed Looking Glass is now available. RIS is focusing on peer quality and data backend modernisation. RIPE Atlas has undergone UI updates and backend improvements, with a focus on improving data availability and performance tooling.
Robert invited attendees to test the newly released software probe firmware for Raspberry Pi and share feedback via email or in-person at the meeting.
Closing
Stephen, Nina, and Massimo thanked the presenters and attendees. Attendees were encouraged to rate talks and continue discussions via the MAT WG mailing list. The session closed with a reminder to join the next MAT WG at RIPE 91 in Bucharest.