Session

SRv6 in Linux Kernel, FRR and eBPF : review the current status and plan the future evolution

Speakers

Stefano Salsano (organizer)
Ahmed Abdelsalam
Andrea Mayer
Carmine Scarpitta
Angelo Tulumello
Emilien Wansart

Label

Nuts and Bolts

Session Type

Bof

Description

Segment Routing over IPv6 (SRv6) has become a cornerstone for modern network programmability by embedding instructions directly into the IPv6 packet header. Standardized under IETF RFC8986, SRv6 has evolved significantly since its initial support in Linux kernel 4.10 over nine years ago. The framework’s capabilities have matured with continuous updates to kernel releases, integrating performance optimizations and feature enhancements. SRv6 employs lightweight tunnel infrastructures, such as seg6 and seg6local, and extends its support to key subsystems like Netfilter and eBPF, fostering its adoption in diverse scenarios.

Prominent open-source projects like FRR, Cilium, and SONiC leverage the Linux kernel’s SRv6 implementation for advanced networking functionalities. FRR facilitates L3VPN services and integrates SRv6 behaviors across its daemons. Cilium harnesses SRv6 with eBPF for efficient container networking, achieving high performance and observability in Kubernetes. Similarly, SONiC leverages SRv6 to deliver scalable routing services and policy management for large-scale deployments.

In the workshop, we will specifically explore how SRv6 innovations have shaped the Linux ecosystem and delve into future opportunities. We will discuss the requirements for enhancing SRv6 support in the Linux kernel, as driven by the demands of projects like SONiC. Additionally, the latest advancements in FRR will be examined to understand how they enable robust L3VPN services and extend SRv6 capabilities. The eBPF framework in Cilium, with its focus on telemetry and traffic engineering, will be shortly presented. Finally, the current limitations of SRv6 in the Linux kernel will be identified, and a roadmap for improvements will be outlined to guide future contributions and collaboration within the networking community. The workshop also features a presentation on an SRv6 performance issue in the Linux kernel and its proposed mitigation. By addressing these themes, the workshop aims to inspire discussions that will drive the next phase of SRv6’s implementation in the Linux ecosystem.

Workshop Program

Tuesday March 11, 2025

09:00 - 09:15 Stefano Salsano
Introduction to the workshop
09:15 - 09:35 Ahmed Abdelsalam
Technical intro to SRv6, IETF status, interoperability status
09:35 - 10:05 Andrea Mayer
SRv6 in Linux kernel: past, present and future
10:05 - 10:20 Ahmed Abdelsalam
SoNIC and SRv6
10:20 - 10:50 Carmine Scarpitta
FRR: status and evolution of SRv6 support
10:50 - 11:10 COFFEE BREAK
11:10 - 11:25 Stefano Salsano
eBPF and SRv6
11:25 - 11:40 Angelo Tulumello
eBPF and SRv6: a use case for RoCEv2 support
11:40 - 12:00 Emilien Wansart
Mitigating the Double-Reallocation Issue for IPv6 Lightweight Tunnel Encapsulations
12:00 - 12:30 Stefano Salsano (Moderator)
Panel discussion on next steps for SRv6 in Linux networking


Workshop Organizer

Stefano Salsano - University of Rome Tor Vergata / CNIT


Speakers

Ahmed Abdelsalam - CISCO Systems
Andrea Mayer - COMMON NET / CNIT
Carmine Scarpitta - CISCO Systems
Angelo Tulumello - CNIT / University of Rome Tor Vergata
Emilien Wansart - University of Liege

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The organization of this workshop has been supported by the European Union - Next Generation EU under the Italian National Recovery and Resilience Plan (NRRP), Mission 4, Component 2, Investment 1.3, CUP E83C22004640001, partnership on “Telecommunications of the Future” (PE00000001 - program “RESTART”).