GDM: A General Distributed Method for Cross-Domain Service Function Chain Embedding

Emerging technologies such as network function virtualization (NFV) and software defined networking (SDN) provide a promising way to implement service function chain (SFC), a chain-ordered set of network functions, to support heterogeneous network services through a shared substrate network. A major challenge in this respect is the SFC embedding with respect to constraints of physical resources. Furthermore, for practical purposes, SFC embedding across multiple domains becomes essential. This challenge is referred to as the cross-domain SFC embedding problem, which is intractable due to various reasons, such as the confidentiality of intra-domain information and the domain's local autonomy. In this paper, we propose GDM, a general distributed method for cross-domain SFC embedding. Besides preserving the privacy and autonomy of domains, GDM guarantees fair competition among domains while balancing loads among domains. It first partitions SFC by utilizing an algorithm that can be instantiated to support different embedding goals. Then it allows domains to embed their assigned segments following their policies. Finally, to improve the capability of the whole substrate network to accommodate more SFCs, it implements domain-level load balancing by migrating the deployed VNFs while avoiding excessive influence on the SFC embedding solution. Evaluation results demonstrate that our method performs better in improving acceptance ratio and optimizing domains' embedding goals compared to the existing methods, and it has better scalability.