Fabric Aggregator: A Flexible Solution to Our Traffic Demand
All traffic that leaves or enters Facbook’s data centers is handled by the fabric aggregation layer. Traffic that flows between buildings in a region is referred to as east/west traffic, while traffic exiting and entering a regions is known as north/south traffic. As we scale our regions and introduce more immersive experiences, both types of traffic continue to grow, although at different rates.
This large scale growth puts pressure on the fabric aggregation tier in terms of port density and capacity per node.
Source: facebook.com