This read-write integer defines the maximum allowed path cost for cost-based routing, used by the PXM so it will not select a route more expensive than this configured level; the default is 255, and the valid range is 1..65535 with a PAR controller but 1..2147483647 with a PNNI controller (also defaulting to 255). An administrator raises or lowers frMaxCost to widen or restrict the set of paths the routing controller is allowed to consider for this connection. For example, on a connection managed by a PNNI controller an administrator could set frMaxCost well above the PAR-imposed 65535 ceiling, taking advantage of PNNI's much larger 2,147,483,647 range if the network topology demands higher-cost paths.