QUIC & multipath
Several paths for one QUIC connection; applicability and manageability of an encrypted transport; access traffic steering, switching and splitting in 5G Advanced.
Ericsson Research · IRTF maprg co-chair · former IAB Chair
Dr. Mirja KühlewindTransport protocols, Internet measurement, and the architecture in between.
Master Researcher at Ericsson Research in Aachen. Six years on the Internet Architecture Board, four of them as Chair; before that IETF Transport Area Director. Author of twenty RFCs, from LEDBAT to AccECN, and co-author of the multipath extension for QUIC.
- 20 RFCs, 2012 – 2026
- IAB member 2020 – 2026, Chair 2020 – 2024
- IETF Transport Area Director 2016 – 2020
- IRTF maprg co-chair since 2016
Research
Protocols that can actually be deployed.
A new mechanism only matters once it survives the Internet as it is, middleboxes and all. Protocol design and measurement belong together.
MASQUE & proxies
Proxying IP and UDP over HTTP, multi-hop relays, stream-aware scheduling over multiple paths, and what privacy partitioning means for the architecture.
Congestion control & ECN
Accurate ECN feedback, LEDBAT, ConEx, SCReAM, TCP SIAD, and the behaviour of CUBIC in low-delay cellular networks. Linux patches included.
Application–network collaboration
Explicit signals between endpoints and the path: path signals, throughput advice for video (SCONE), on-path explicit measurement.
Seeing the Internet as it is
Path transparency, deployability of extensions, passive latency measurement with three bits, and workshops that turn data into evidence. Co-chair of the IRTF's maprg.
Internet architecture for AI agents
Auditing agent delegation and interactions, best practices for crawlers, and how agents are discovered on the network.
Path
Stuttgart, Zurich, Aachen. The IETF throughout.
At Ericsson, Mirja works foremost on the design of transport protocols with a focus on congestion control, as well as on Internet measurements investigating the deployability of new protocols or protocol extensions.
- 2019 – nowEricsson Research, Herzogenrath (Aachen)
Master Researcher, Networks. Transport protocol design with a focus on congestion control, and Internet measurements on the deployability of new protocols and extensions.
- 2020 – 2026Internet Architecture Board (IAB)
Member for six years, IAB Chair 2020 – 2024 and as such ex-officio member of the IESG. Program committee member of the IAB workshops on COVID-19 Network Impacts (2020), Analyzing IETF Data (2021) and Barriers to Internet Access of Services (2024), and co-author of their reports. IESG liaison to the IAB 2019 – 2020.
- 2016 – 2020IETF Transport Area Director
Four years on the Internet Engineering Steering Group (IESG), April 2016 to March 2020, responsible area director for working groups including TCPM, MPTCP, AQM, TCPINC and RMCAT.
- 2014 – 2019ETH Zurich, Networked Systems Group
Postdoctoral researcher at the Computer Engineering and Networks Laboratory (TIK). Coordinator of the EU H2020 project MAMI, Measurement and Architecture for a Middleboxed Internet.
- 2009 – 2014University of Stuttgart, IKR
Researcher at the Institute of Communication Networks and Computer Engineering (IKR); PhD 2015 with the thesis Scalable Increase Adaptive Decrease: congestion control supporting low latency and high speed (published 2016). Co-chair of the IETF rmcat working group from 2012.
- 2009FAU Erlangen-Nuremberg
Diploma degree in Communication and Information Technologies.
RFCs
Twenty published standards and reports.
From the RFC Editor's index. Internet-Drafts in progress and the IETF roles are on the IETF page.
NumberTitleStatusYear
RFC 9768More Accurate Explicit Congestion Notification (AccECN) Feedback in TCPStd2026RFC 9928DHCPv4 over DHCPv6 with Relay Agent SupportStd2026RFC 9707Report from the IAB Workshop on Barriers to Internet Access of Services (BIAS)Info2025RFC 9622An Abstract Application Programming Interface (API) for Transport ServicesStd2025RFC 9614Partitioning as an Architecture for PrivacyInfo2024RFC 9501Open Participation Principle regarding Remote Registration FeeBCP2023RFC 9484Proxying IP in HTTPStd2023RFC 9419Considerations on Application - Network Collaboration Using Path SignalsInfo2023RFC 9400Guidelines for the Organization of Fully Online MeetingsInfo2023RFC 9312Manageability of the QUIC Transport ProtocolInfo2022RFC 9308Applicability of the QUIC Transport ProtocolInfo2022RFC 9307Report from the IAB Workshop on Analyzing IETF Data (AID) 2021Info2022RFC 9075Report from the IAB COVID-19 Network Impacts Workshop 2020Info2021RFC 8546The Wire Image of a Network ProtocolInfo2019RFC 8095Services Provided by IETF Transport Protocols and Congestion Control MechanismsInfo2017RFC 7837IPv6 Destination Option for Congestion Exposure (ConEx)Exp2016RFC 7786TCP Modifications for Congestion Exposure (ConEx)Exp2016RFC 7663Report from the IAB Workshop on Stack Evolution in a Middlebox Internet (SEMI)Info2015RFC 7560Problem Statement and Requirements for Increased Accuracy in Explicit Congestion Notification (ECN) FeedbackInfo2015RFC 6817Low Extra Delay Background Transport (LEDBAT)Exp2012Talks
Recent presentations
- Internet Governance Forum (IGF 2025)IAB networking session: the roles of the IAB and the IRTF within the Internet architecture · 2025
- European Internet Forum (EIF) eventRisks of Internet Fragmentation · 2024
- RIPE 86 plenaryIETF Overview of Technical Work and Hot Topics · 2023
- IETF 118 plenaryIAB Report · 2023
- FCC CSRIC VIII WG1QUIC and HTTP/3 · 2022
Press & writing
Interviews and blog posts
- Ericsson BlogVideo traffic treatment 2.0: What's the secret recipe of SCONE? · December 2025
- IETF BlogExperiences at IGF 2025 · July 2025
- Ericsson BlogRelying on relays: The future of secure communication · June 2022
- Ericsson BlogA collaborative approach to encrypted traffic · June 2020
- Ericsson BlogDNS security and why it's time for change · March 2020
Publications
Papers, reports, a dissertation
From re-ECN in 2010 to stream-aware scheduling for QUIC proxying in 2026, grouped by year, with PDFs where they may be shared.
ServiceCommittees and workshops
Programme committees for IMC, PAM, TMA and ANRW over a decade; general co-chair of the IAB SEMI workshop, ANRW 2020 programme co-chair, chair of the CSWS and MNM workshop series.
CodeLinux patches
ECN fallback, AccECN, TCP SIAD, LEDBAT and sysctl helpers for experiments, as published with the papers.