The current Internet is facing unprecedented demands, and the challenges and protocols were designed and incorporated into the system as a patchwork for solving many issues. The patchwork approach of non-integrated security mechanisms does not appropriately address the problems, because the problem lies with the architecture itself and not of protocols. Flexible network architecture is being explored as a new approach to address the issues of technical and non-technical challenges of the present Internet. Many flexible network architectures were designed to address the infrastructural problems of the current Internet. Service-oriented network architecture is one that is based on service-oriented architecture supporting short-term and long-term demands that evolve. It offers various flexible services without considering the threats that are raised due to lack of security in the architecture. The paper discusses the security requirements for the proposed architecture in order to avoid and tolerate the attacks of the network. Security and Communication Networks. Copyright (c) 2015 John Wiley & Sons, Ltd