This bitmask indicates optional session values for this tunnel. The following describes these bit fields: fastReroute This flag indicates that any tunnel hop may choose to reroute this tunnel without tearing it down. This flag permits transit routers to use a local repair mechanism which may result in violation of the explicit routing of this tunnel. When a fault is detected on an adjacent downstream link or node, a transit router can reroute traffic for fast service restoration. mergingPermitted This flag permits transit routers to merge this session with other RSVP sessions for the purpose of reducing resource overhead on downstream transit routers, thereby providing better network scalability. isPersistent Indicates whether this tunnel should be restored automatically after a failure occurs. isPinned This flag indicates whether the loose- routed hops of this tunnel are to be pinned. recordRoute This flag indicates if the signaling protocol should remember the tunnel path after it has been signaled. bandwidthProtect This flag indicates whether fast reroute bandwidth protection is desired. nodeProtect This flag indicates whether fast reroute node protection is desired.