SDN traffic engineering provides a simpler and more optimal approach compared to traditional offline and on-device traffic engineering. It uses segment routing to encode paths, push-based telemetry for real-time traffic matrices, and an SDN controller running a traffic engineering application to optimize paths network-wide in a centralized manner. This approach alleviates congestion, uses as few tunnels as necessary, and easily adapts to failures or network changes.
21. Traffic Engineering as an SDN App
SDN App manages traffic demand
• Current as well as future
• IGP does not have to signal available bandwidth
• Push based telemetry or netflow based matrices can be generated
SDN App computes paths and allocates bandwidth
• Centralization yields better resource optimization
• Only creates as many tunnels as necessary
SDN App adapts to failures and repairs
• No race conditions after failures and repairs
Segment routing can be used as a simplification
• SDN controller makes this an abstraction for the APP
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