Open-source software has already demonstrated its potential in the fields of operating systems and applications, as it allows enterprises and telcos to adapt, extend, and improve software according to their needs, while at the same time sharing part of the development cost. 

 However, network softwarization introduces additional constraints such as the necessity to provide service guarantees, the challenge to orchestrate massively distributed systems, the obligation to provide end-to-end services, spanning across multiple technological domains and traversing different administrative boundaries, the requirements to comply with a strict regulatory framework, and more. 

 This second Workshop on Open-Source Software Networking (OSSN-2017) aims at bringing together researchers, universities, companies, standardization bodies, and open-source communities to discuss the possible role of the open-source software in future network infrastructures and to share experiences on developing and operating open-source software-centric networking tools and platforms. 

 In addition, OSSN-2017 aims at providing a vibrant atmosphere for representatives of different communities to setup a common discussion about their roadmap toward future network services and and to increase the cooperation between different communities. Finally, it aims at facilitating the collaboration between different actors, such as individual researchers (e.g., PhD students) contributing to existing established projects, and between different projects. 

 Full and short (work-in-process) papers are solicited to discuss experiences on development, deployment, operation, and experimental studies around the overall lifecycle of open-source software networking.