We are pleased to welcome you to the 3rd symposium dedicated to PhD students which is taking place during the 8th IEEE NFV-SDN conference. The NFV-SDN Doctoral Symposium is committed to fostering collaboration amongst PhD students and experts from all communities researching and working in the areas of Network Function Virtualization (NFV) and Software Defined Networks (SDN). It offers a unique opportunity for PhD students to present their latest research results, discuss new research ideas, and to gather valuable expert feedback on their work from experienced researchers from both industry and academia. Moreover, it is a place for mentoring and to get in touch with student peers working in the same field.