Abstract: Aspects and implementations of the present disclosure generally relate to use of a multi-chassis link aggregation for high performance and resilience in wide-area networking. In one aspect, the disclosure relates to a system that includes a switch fabric. The fabric includes at least a plurality of edge network devices, a set of internal switch devices, and a plurality of internal network links coupling each edge network device to at least a subset of the set of internal switch devices. The system includes a network controller coupled to the switch fabric, configured to maintain at least one link aggregation comprising a logical grouping of externally facing network interfaces of at least two of the plurality of edge devices. The network controller is configured to monitor internal link performance characteristics and determine throughput characteristics for each link aggregation over time based at least in part on current internal link performance characteristics.