Network connectivity is the ability of systems to exchange traffic over internal and external network paths. It depends on routers, switches, cables, links, routing policy, and the capacity available between sites and services.
In cyber security, connectivity matters because availability is a core control objective. If links are slow, degraded, or cut, users may lose access even when servers and applications are intact. Attackers can exploit this by targeting network equipment, flooding links, or disrupting routing, while defenders monitor latency, packet loss, failover health, and alternate paths. In a physical or cyber-physical disruption, reduced connectivity can force traffic to reroute and reveal whether redundancy and recovery planning are effective.