SDN Architecture and Southbound APIs for IPv6 Segment Routing Enabled Wide Area Networks

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The SRv6 architecture (Segment Routing based on IPv6 data plane) is a promising solution to support services like Traffic Engineering, Service Function Chaining and Virtual Private Networks in IPv6 backbones and datacenters. The SRv6 architecture has interesting scalability properties as it reduces the amount of state information that needs to be configured in the nodes to support the network services. In this paper, we describe the advantages of complementing the SRv6 technology with an SDN based approach in backbone networks. We discuss the architecture of a SRv6 enabled network based on Linux nodes. In addition, we present the design and implementation of the Southbound API between the SDN controller and the SRv6 device. We have defined a data-model and four different implementations of the API, respectively based on gRPC, REST, NETCONF and remote Command Line Interface (CLI). Since it is important to support both the development and testing aspects we have realized an Intent based emulation system to build realistic and reproducible experiments. This collection of tools automate most of the configuration aspects relieving the experimenter from a significant effort. Finally, we have realized an evaluation of some performance aspects of our architecture and of the different variants of the Southbound APIs and we have analyzed the effects of the configuration updates in the SRv6 enabled nodes.

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Conference Paper
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Conference Paper
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In Chapter 1, we presented an overview of networking and looked at the structure and usage of different network protocols such as TCP, UDP, IP, and DNS. In this chapter, we start with network programming using classes from the System.Net namespace.
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he was one of the beneficiary of the scholarship "Orio Carlini" granted by the Italian NREN GARR. His main research interests focus on Software Defined Networking, Network Function Virtualization, Virtualization and IPv6 Segment Routing. He worked as researcher in several projects founded by the EU
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SoftFire Project. [Online]. Available: Pier Luigi Ventre received his PhD in Electronics Engineering in 2018 from University of Rome "Tor Vergata". From 2013 to 2015, he was one of the beneficiary of the scholarship "Orio Carlini" granted by the Italian NREN GARR. His main research interests focus on Software Defined Networking, Network Function Virtualization, Virtualization and IPv6 Segment Routing. He worked as researcher in several projects founded by the EU and currently he is a post-doctoral researcher at CNIT.
He is a PhD candidate in Tarbiat Modares University, Tehran, Iran. Currently, he is spending his sabbatical period in University Rome "Tor Vergata". His main research interests are Network QoS, media streaming over the Internet
  • Tajiki Mohammad Mahdi
Mohammad Mahdi Tajiki graduated from Electrical and Computer Engineering School of Tehran University, Tehran, Iran. He is a PhD candidate in Tarbiat Modares University, Tehran, Iran. Currently, he is spending his sabbatical period in University Rome "Tor Vergata". His main research interests are Network QoS, media streaming over the Internet, data center networking, traffic engineering, and software defined networking (SDN).