Due to a ransomware attack, the wiki was reverted to a July 2022 version. . We apologize for the lack of a more recent valid backup.
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Switch objects are associated with several types of states that limit the types of actions applicable to it. Two of the primary states tied to a switch are its Channel State, and the ONOS instance's role.
Channel state
The OFChannelHandler implements the channel state FSM in the ChannelState Enum. Each enum value represents the various points in the OpenFlow handshake. The following flowchart represents this FSM.
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Driver-specific handshakes are implemented per OFSwitchImpl* class.
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The role of an ONOS instance describes its read and write permission regarding the Switch object. In the multi-instance setting, one ONOS instance will be a Master with full control over the network switch, and the rest will be Equals only capable of reading state information from a network switch. The roles are enforced both at the OpenFlowSwitchDriver level by the RoleManager (not shown), and at a protocol-neutral level by the Cluster Subsystem.
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