A method of neighbor discovery protocol mediation over an Internet Protocol interworking virtual leased line the method comprising: receiving (202, 302, 402, 502) a ICMPv6 discovery message at a Provider Edge device of the virtual leased line, wherein the Provider Edge device is a IPv6 node; making (204, 304, 404, 504) a determination whether or not the ICMPv6 discovery message was received from a local attachment circuit of the virtual leased line; responsive to a determination that the ICMPv6 discovery message was not received from the local attachment circuit: inspecting (210, 310, 410, 510) the ICMPv6 discovery message to learn an IPv6 interface address of a far-end Customer Edge device of the virtual leased line, wherein the far-end Customer Edge device is a IPv6 node; altering (212, 312, 414, 514) the ICMPv6 discovery message; and forwarding (214, 314, 416, 516) the altered ICMPv6 discovery message to a local Customer Edge device over the local attachment circuit, wherein the local Customer Edge device is a IPv6 node, and responsive to a determination that the ICMPv6 discovery message was received from the local attachment circuit: inspecting (206, 306, 406, 506) the ICMPv6 discovery message to learn any IPv6 interface addresses and link-layer address provided therein, and forwarding (208, 308, 408, 508) the ICMPv6 discovery message unmodified over a pseudowire of the virtual leased line. receiving (202, 302, 402, 502) a ICMPv6 discovery message at a Provider Edge device of the virtual leased line, wherein the Provider Edge device is a IPv6 node; making (204, 304, 404, 504) a determination whether or not the ICMPv6 discovery message was received from a local attachment circuit of the virtual leased line; responsive to a determination that the ICMPv6 discovery message was not received from the local attachment circuit: inspecting (210, 310, 410, 510) the ICMPv6 discovery message to learn an IPv6 interface address of a far-end Customer Edge device of the virtual leased line, wherein the far-end Customer Edge device is a IPv6 node; altering (212, 312, 414, 514) the ICMPv6 discovery message; and forwarding (214, 314, 416, 516) the altered ICMPv6 discovery message to a local Customer Edge device over the local attachment circuit, wherein the local Customer Edge device is a IPv6 node, and inspecting (210, 310, 410, 510) the ICMPv6 discovery message to learn an IPv6 interface address of a far-end Customer Edge device of the virtual leased line, wherein the far-end Customer Edge device is a IPv6 node; altering (212, 312, 414, 514) the ICMPv6 discovery message; and forwarding (214, 314, 416, 516) the altered ICMPv6 discovery message to a local Customer Edge device over the local attachment circuit, wherein the local Customer Edge device is a IPv6 node, and responsive to a determination that the ICMPv6 discovery message was received from the local attachment circuit: inspecting (206, 306, 406, 506) the ICMPv6 discovery message to learn any IPv6 interface addresses and link-layer address provided therein, and forwarding (208, 308, 408, 508) the ICMPv6 discovery message unmodified over a pseudowire of the virtual leased line. inspecting (206, 306, 406, 506) the ICMPv6 discovery message to learn any IPv6 interface addresses and link-layer address provided therein, and forwarding (208, 308, 408, 508) the ICMPv6 discovery message unmodified over a pseudowire of the virtual leased line.