Connects the campus to the fibre backbone and other data centres for low-latency interconnect - the layer that makes a data centre useful beyond its own four walls.
Why it matters
Compute is only valuable if it can reach users and other systems quickly; interconnect quality determines latency-sensitive workload viability.
Where the value pool sits
Fibre and networking-equipment makers sell both backbone-capacity buildout and ongoing capacity upgrades as traffic grows.