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VOLTHA/SEBA Builds on Long Term Support Release

Jan 5, 2022
Andrea Campanella
Andrea Campanella About the author

VOLTHA v2.9 Release Now Available

ONF is pleased to announce the release of VOLTHA™ v2.9 along with an updated ONOS® release (v2.5.5). This is the first release following the v2.8 Long Term Support (LTS) release. 

VOLTHA and ONOS are already deployed in production networks at Deutsche Telekom (DT) and Türk Telekom (TT). Deployment feedback, strong collaboration and ongoing development with these operators continues to enable a tight loop of ever-increasing software quality and feature richness.

VOLTHA v2.9 focused on two main changes, specifically moving from Kafka to gRPC for inter-container communication and the rewrite of the OLT app.  Effort was also focused on porting bug fixes and maintaining the VOLTHA v2.8 LTS release, as per the LTS strategy. All of the work was made possible by a great and well coordinated community. 

Thanks to the combined effort of ADTRAN, Ciena and ONF, VOLTHA v2.9 removed the use of the Kafka bus for inter-container communication, greatly simplifying the architecture of VOLTHA and enhancing performance and ensuring replies from adapters. This change opened a Pandora's box of time-based assumptions that were made in the adapters and in the core, requiring a thorough evaluation and several bug fixes across the stack to avoid deadlock scenarios and failing operations. Through the development process we were all  amazed at how much a change in the communication system could affect timing in so many different places. Through this change we enhanced the performance of the VOLTHA stack and ensured request/response via direct gRPC calls, allowing for results according to end-to-end operations. In the end the change was a lot more effort then expected but it provided additional benefits including many fixes. Several applicable fixes were backported to VOLTHA v2.8, further strengthening the stability of the LTS release.  

ONF (mostly Matteo, thanks!) rewrote the ONOS OLT app, moving away from a complicated and tedious Java completable future based approach for subscriber and flow configuration to a simpler, more streamlined queue mechanism, where events are pushed and processed in order. A thank you goes to the GO channels for inspiration! With the rewrite the app is achieving faster turnaround time for requests and events, and fixes the 1024 ATT issue at scale. With speed comes also code quality and simplification, allowing for an easy integration of the Telecom Italia workflow (more on that later). A huge thanks to Netsia for thorough testing and reviews of the new app during development. 

With VOLTHA v2.9 a new operator more actively participated in the community, Telecom Italia, TIM for short. TIM, with the help of Reply and ONF, successfully integrated their transparent OLT tagging in the olt app, adapter and agent, ensuring no VLAN operation taking place at the OLT. This was the final missing possibility for VLAN operations, which means VOLTHA now supports double tagging, transparent ONT and transparent OLT. Now you just have to deploy it in your network. 

As usual great work came from the openonu adapter group, with ADTRAN, Netsia, Tibit, and ONF all coming together to deliver prioritized OMCI sending a Relaxed decoding and storing of unknown MEs, PM counter Reset and Flow serialization and queueing mechanisms. It’s amazing to see the level of completeness the adapter is reaching, a testament to the great work of this team. 

The platform’s stability has increased thanks to bug fixes contributed throughout the stack, from a small code change in ONOS (v2.5.5) that enabled ISSU to a full blown analysis and refactor of the leftover data in ETCD and the ONU after device deletion or subscriber unprovisioning, further lowering the storage footprint of VOLTHA data. Broadcom Abstraction Layer (BAL) has been moved to BAL setting the stage for the 3.12 migration to ensure support of newer chipsets. ADTRAN also provided ONU upgrade fixes. 

The test suite for VOLTHA has been vastly enhanced  thanks to ADTRAN, Netsia and ONF, with new Multi-uni and multi-olt tests for openonu adapter suite, software update success and failure scenarios, 5 new Türk Telecom multicast tests, continuous background ping during container restarts, ONU delete and re-add, Empty device, subscriber and service information after deletion. We now run more than 400 tests nightly on physical and virtual pods.This is truly a significant accomplishment that accelerates our ability to identify bugs quickly enabling faster resolution. 

During VOLTHA v2.9 also a stronger collaboration with BBF started, aimed at integrating VOLTHA into the BBF environment by understanding which BBF standards and models map to VOLTHA functionality and exposing them, both on the northbound and the southbound. 

In VOLTHA v2.9 we also certified two brand new white box OLTs, the Radisys RLT-1600G GPON and the Radisys RLT-1600X COMBO and a grey-box one, the ADTRAN 6320X COMBO OLT. All three of these were ported to  A complete list of hardware certified under ONF’s Continuous Certification Program with the VOLTHA v2.9:

  • Edgecore ASXvOLT 16 XGSPON 
  • Edgecore ASGvOLT64 GPON OLT
  • Edgecore AS6712 switch
  • Edgecore AS7712 switch
  • Radisys RLT-3200G GPON OLT
  • Radisys RLT-1600G GPON OLT 
  • Radisys RLT-1600X COMBO OLT

You can find more details about the v2.9 release in the VOLTHA v2.9 release notes

VOLTHA v2.9 Techinar
ONF will be hosting a virtual VOLTHA v2.9 Techinar on January 11th at 9:00am PST during which we will provide an in-depth view of the release features and an opportunity for attendees to interact with project experts during a live Q&A. 

Register now to join us.

Finally, VOLTHA v2.9 builds on the LTS foundations and begins a new phase in the project. Looking ahead at the next LTS release in December 2022, where new features like IPv6, Plain Old Telephone (POTS) server and a micro service controller will be included. A huge thanks goes to all of the people, teams and companies that have participated in the release and work every day to achieve the success of this open source project. None of the results in VOLTHA could be achieved without the dedication, contributions, and expertise of the VOLTHA community, the ONF team and the ONF members and partners. I really want to thank each and every one. A special appreciation goes to the ONF team who always do amazing work to enhance and ensure the success of VOLTHA.

Andrea Campanella & the VOLTHA team


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ABOUT THE AUTHOR Andrea Campanella
Andrea CampanellaMember of Technical Staff
Andrea joined ONF in October 2015 as a Research Scholar Intern. Andrea received a Bachelor’s degree in Digital Communication and is majoring in Computer Science at the Public University of Milan, Italy, with a focus in computer networks and SDN technology. At ONF, Andrea is on the ONOS core development team focusing on southbound architecture, protocol integration and driver subsystems. Andrea is also part of the A-Team: the ambassador program steering team and is active in shaping the ONOS community. In his free time Andrea enjoys photography, hiking, sailing, biking, and playing basketball.