Sumários
Aula 12
4 Novembro 2021, 16:00 • Rita Sousa
The current laboratorial lecture taught how to deploy a SDN-based network formed by a SDN controller (i.e. Ryu) and several OpenvSwitch (OVS). The OVSs connected in a serial topology enable the interconnection between two hosts. The current lecture also taught how the OpenFlow (v1.0) protocol is used between the SDN controller and each OVS. In addition, it is studied how some important system functionalities, such as topology discovery and network monitoring, can be supported. First, to implement the functionality of topology discovery, the Link Layer Discovery Protocol (LLDP) is used. Second, for ensuring the network monitoring, a python thread runs periodically, i.e. once each pre-defined time window, in the SDN controller. Each time that thread runs, it enforces the exchange of some OF messages through the control channel that exists between the SDN controller and each switch. Those OF messages enable the SDN controller to be updated with relevant statistical information about switch ports and flow rules.
Aula 11
4 Novembro 2021, 14:30 • Rita Sousa
Message Types in OF1.0. Controller Discovers New Switch. Negotiation of OpenFlow Version. Controller Gets Switch Characteristics. Reactive Control. Proactive Control. Topology: Link Discovery. Monitoring of Topology Status. Next Laboratory.
Aula 10
28 Outubro 2021, 16:00 • Rita Sousa
During the current laboratory lecture, the students are expected to fulfill the next goals: i) Learn how to create an emulated network using Mininet; ii) Understand how the given code of a python application, which uses some libraries of the Ryu SDN package, listens the initial request from an OVS switch, accepts that request, initializes the switch, and then controls the switch; iii) Analyze and experiment several (four) python applications that offer various SDN based functionalities over the same topology.
Aula 9
28 Outubro 2021, 14:30 • Rita Sousa
Protocol OpenFlow v1.0. Message Types in OF1.0. Controller-Switch Protocol Session. Ryu Open Source SDN Controller in Python. Major Components of the Ryu Architecture. Ryu Libraries. OpenFlow Protocol and Controller. Managers and Core Processes. RYU Northbound. Ryu Applications. Functional Architecture of a Ryu Application. Running a Ryu Application. Writing a Ryu Application. Writing a Ryu Application Bootstrap. Writing a Ryu Application Handler of a SwitchFeatures Event. Mininet Network Emulator. Mininet Simple Topology. Mininet Several Commands. Mininet More Commands. Next laboratory. Launch the topology. Four Tests to Achieve some Learning Goals.
Aula 8
21 Outubro 2021, 16:00 • Rita Sousa
During the current laboratory lecture, the students are expected to learn how to deploy virtualized memory-based routers, using two methods: i) the first method uses two OVS switches configured with flow rules that use the local port of each switch, which is essential for incorporating the kernel routing table in the routing decision of each packet: ii) the second method instantiates a namespace container and configures it as a standalone router. Meanwhile, the students also learn how to deploy a NAT router.