This read-only setting reports whether the LCN and VPID address space for switched virtual circuits is shared across every port on the card (cardBased) or kept separate per port (portBased). An administrator checks this to understand how changing the SVC LCN or VPID low/high range on one port will behave: under the default cardBased mode a change on one port propagates to all ports on the card. For example, if this object reads cardBased(2), widening ausmPortSvcVpidHigh on port 1 will also widen the effective VPID range seen on ports 2, 3, and 4.