Partially Symmetric Service Function Chains
Hajar Hantouti, Nabil Benamar · 2019
With the variety of proposed networking services and the growing requirements of subscribers, networking infrastructures strive to offer the best quality of service. Complex services, such as security services require a composition of intermediate Service Functions (SFs). Service Function Chaining (SFC) is a new trending networking concept that enables composing and forcing the order in which service functions are invoked. With the emergence of Software Defined Networks (SDN) and Network Function Virtualization (NFV), the complexity of deploying service chains is reduced. However, configuring traffic symmetry remains a complex operation, especially with composed SFs. Ensuring traffic symmetry for chains is still challenging, particularly with chains of different symmetry requirements. In this paper, we discuss the problem of traffic symmetry for SFC and showcase the issue of partial symmetry chains. Finally, we present a new approach that calculates the reverse path of service chains composed of symmetrical and asymmetrical SF's requirements. Our results show that our proposed solution reduces the forwarding state and potentially reduces the traffic delay.