Today’s networks are maintained by “masters of complexity”:
… high-level intent (policies) must correctly map to
According to a recent survey of network operators, 35% of
networks generate more than 100 tickets per
month. …
the limitations of our current ad hoc troubleshooting tools are a direct consequence of the architecture in which these tools must operate.
not propose any new systems; instead, … builds an overall picture of systematic troubleshooting in SDNs.
The physical view has a one-to-one correspondence with the physical network, and it is the job of the network operating system to configure the corresponding network devices through a protocol such as OpenFlow.
whether the abstract configuration of each network device, e.g., a single match-action table, matches the low-level, hardware-specific configuration, e.g., registers to configure a forwarding pipeline. … SOFT tool
knowing the operator’s intent:
implicitly expressed as the combination of all protocol configurations over all nodes. To infer intent, one must gather … understand the composition of each protocol config (the precedence rules between protocols operating at the same data-plane layer)
checking network behavior against intent
improve invariant checkers?
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