US Patent 7779136 Secure neighbor discovery between hosts connected through a proxy

A method, a proxy and a host are provided for securing neighbor discovery (ND) signaling between hosts when the hosts are connected through the proxy. A first host sends an original ND message comprising a first signature based on an address of the first host. The proxy removes the address of the first host and substitutes its own address in a modified ND message. The proxy then places a copy of the address of the first host in a new field and builds a proxy signature based on the own address of the proxy and on the new field. The new field and the proxy signature are added to the modified ND message. A second host receives the modified ND message from the proxy and verifies the proxy signature. The second host reconstructs the original ND message content and then verifies the first signature.