Patent ID: 9641551
Date: 2017-05-02
CPC Classifications: H04L

Claim:
1. A method for routing, the method comprising: establishing an overlay network, comprising a plurality of overlay edge routers and an overlay controller (OC); wherein each overlay edge router (OER) is in communication with the overlay controller via a secure tunnel established through a core transport network; the plurality of overlay edge routers are in communication with each other via peer-to-peer links established through the core transport network; at least a first overlay edge router of the plurality of overlay edge routers is located between a first domain and a first Network Address Translation (NAT) router associated with the first domain; at least a second overlay edge router of the plurality of overlay edge routers is located between a second domain and a second NAT router associated with the second domain; and said first and second NAT routers have interfaces to a cores transport network; wherein each overlay edge router includes a private IP address and a public IP address; receiving Internet Protocol (IP) packets from a source host device located in the first domain bound for a target host device located in the second domain; wherein said receiving is by the first overlay edge router; processing each IP packet for transmission to the target host device with Internet protocol Security (IPSec IP) authentication including: calculating authentication data for the IP packet using the private IP address of the second overlay edge router as a destination IP address, and the public IP address of the first overlay edge router as a source IP address; modifying the IP packet by inserting the authentication data into the IP packet; inserting an outer header for the modified IP packet including the private IP address of the first overlay edge router as the source IP address, and the public IP address of the second overlay edge router as the destination IP address; and forwarding the modified IP packet to the first NAT router.