Project goal

The Extreme Flow Optimizer (EFO) project aims to enhance Extreme Networks’ EFO application. Our plan is to use it, in conjunction with the Extreme Workflow Composer (EWC) software, to build an automated traffic-steering system for our network. EFO improves visibility of network traffic and manages volumetric DDoS threats by applying dynamic flow steering. EWC is an event-driven IT automation platform, well suited for network automation purposes.

R&D topic
R&D Topic 1: Data-centre technologies and infrastructures
Project coordinator(s)
Tony Cass
Technical team members
Adam Krajewski, Stefan Stancu, Edoardo Martelli, David Gutierrez Rueda
Collaborator liaison(s)
Manjunath Gowda, Murtaza Bawahir, Mythil Raman, Yousuf Hasan, Christoph Kaelin, Giacomo Bernardi, Salvador Ferrer


Project background

As technology evolves, there are more and more use cases where traditional, static network configurations prove too rigid. This project uses the EFO and EWC software to provide increased programmability and flexibility in our network.

The project has led to upgrades to CERN’s intrusion detection system (IDS), which relies on EFO and EWC to achieve scalability and to implement advanced features, such as the offloading of the inspection of bulk data transfers.

Recent progress

Throughout 2018, important contributions were made to the general EFO product development, and the IDS prototype at CERN was brought to maturity and put into production.

In the first part of the year, the CERN fellow funded by Extreme Networks continued to be fully integrated in the EFO development team. There, he made a major contribution to the redesign of the software architecture, making use of Docker containers. The fellow also provided expert consultancy regarding EFO to a major customer of Extreme Networks in Switzerland.

Later in the year, effort was directed into finalising the traffic orchestrator for the upgraded IDS system at CERN. The IDS receives a copy of the traffic that crosses CERN’s network boundary and load-balances it across a pool of servers, each running the open-source Bro Network Security Monitor system. The traffic orchestrator uses Extreme Networks’ SLX 9540 hardware platform, a high-end data-centre switch with advanced hardware capabilities for traffic orchestration. In addition, the EWC software provides increased automation capabilities through modular and configurable workflows, abstracting the network device configuration.

Next steps

The EFO project came to a close in October 2018, following three years of successful work. Throughout the project’s lifetime, numerous contributions and enhancements were made to the EFO software, and the project ultimately resulted in an upgraded, scalable IDS for CERN. This IDS relies on a traffic orchestrator that makes use of both hardware and software from Extreme Networks.


    M. Abdullah, Network Automation with Brocade Workflow Composer (15 August), Presented at CERN openlab summer students’ lightning talks, Geneva, 2017.
    A. Krajewski, Lightning talk: Brocade Flow Optimizer (21 September), Presented at CERN openlab Open Day, Geneva, 2017.
    A. Krajewski, Network Automation for Intrusion Detection System (18 October), Presented at HEPIX Fall 2017 Workshop, KEK, Tsukuba, Japan, 2017.
    A. L. Krajewski, Extreme Networks project Highlights (11 January). Presented at CERN openlab technical workshop, Geneva, 2018.
    A. L. Krajewski, Bro optimisations and network topologies (27 June). Presented at WLCG Security Operations Center WG workshop, Geneva, 2018.