The object path of the parent device. The expected set of GRE flags for incoming packets. (The values are specified by the GRE specification. On Linux, they are defined in <linux/if_tunnel.h>. Eg, GRE_KEY for the 'Key Present' bit.) The set of GRE flags to use for outgoing packets. (The values are specified by the GRE specification. On Linux, they are defined in <linux/if_tunnel.h>. Eg, GRE_KEY for the 'Key Present' bit.) Expected input key (if the "Key Present" bit is set in the input flags). Output key (if the "Key Present" bit is set in the output flags). The local end of the tunnel. The remote end of the tunnel. The value to use in the IP TTL field for tunnel packets. The value to use in the IP ToS field for tunnel packets. Whether path MTU discovery is performed. A dictionary mapping property names to variant boxed values