An end point address of a generic routing encapsulation (GRE) tunnel is obtained by forwarding a data packet through the GRE tunnel to devices at a multicast address. The data packet includes a logical address of a GRE tunnel end point device. A reply to the data packet is received from a remote GRE...http://www.google.fr/patents/US6779051?utm_source=gb-gplus-shareBrevet US6779051 - Determining an end point of a GRE tunnel
