Elastic and dynamic orchestration of service function chains for 5G networks
Ahmed Mohamed Medhat Mohamed Ahmed Hassan · DepositOnce · 2017
As the telecommunication community moves towards the 5th Generation Mobile Networks (5G), Softwarized Networks are leading the way to a radical development in the Network Operators' infrastructures. New emerging technologies such as Network Function Virtualization (NFV) and Software-Defined Networking (SDN) are the key enablers for managing on-demand resources in softwarized networks. Focusing on the Mobile Core Network architecture, being the most relevant part in future 5G infrastructures, Service Function Chaining is foreseen to be the solution for dynamically steering traffic across multiple Service Functions (SFs) residing in the SGi-Local Area Network (LAN). The increase in the heterogeneous traffic, resulting from augmented number of devices and services, impose multiple challenges when managing Service Function Chains (SFCs). Some applications in the 5G context have critical Quality of Service (QoS) requirements in terms of data latency and demanded throughput such as voice and video calls which are crucial even during stressed situations in the core network. However, the legacy SFC models have limited adaptability and flexibility; they treat the traffic generated by heterogeneous applications similarly regardless of its context or its source. Recently, several related works and specifications have been proposed, and several activities in the open source community have been implemented as prototype solutions to cope with these new challenges and requirements. However, none of the existing works fulfill most of the required functionalities of orchestrating SFCs in NFV-/SDN-based networks, i.e., lifecycle management, in a single and extensible framework. This thesis proposes X-FORCE, an extensible framework for orchestrating SFCs elastically considering the whole lifecycle of SFCs. X-FORCE is compliant to the ETSI NFV Management and Orchestration (MANO) reference architectural model, IETF SFC architecture and ONF SFC architecture. The objectives of X-FORCE are to deploy SFCs and their data paths automatically, support the heterogeneity of SFC network requirements, update the SFC data paths dynamically, manage the full lifecycle of SFCs, and enhance the overall network QoS performances while reducing the costs in network operators' infrastructures. The contributions presented in this thesis can be summarized in four segments: First, a related work review and a requirement analysis were performed. Second, challenges, limitations, opportunities and design aspects for specifying an SFC orchestration model were formulated. Third, a conceptual model, X-FORCE, was specified and its prototypical implementation was realized and integrated as an addition to the Open Baton platform to prove their value in a standard prototype architecture. Fourth, a generic evaluation framework was developed according to the identified requirements to evaluate the limitations of existing and proposed solutions and a performance evaluation of the X-FORCE system is carried out providing a practical view on how to realize its proposed functionalities as part of selected SGi-LAN use cases.