The limit on the total number of TCP connections this device's own TCP stack can support, or -1 if the maximum is dynamic. On a Check Point gateway this specifically caps TCP sessions terminating on the gateway's own stack, distinct from the firewall's connection table limit which governs passthrough traffic, so hitting this limit would manifest as management access itself becoming unreliable even while regular traffic keeps flowing. Example: tcpMaxConn reporting -1 confirms this gateway's stack sizes its connection table dynamically rather than enforcing a hard cap that could someday be exhausted.