Methods and apparatus for remapping public network addresses on a network to an external network via an intermediate network

A method, comprising:

• assigning, by one or more devices on a provider network, subsets of a plurality of Internet Protocol (IP) addresses to customers as customer IP addresses and subsets of a plurality of resource instances on the provider network to the customers as customer resource instances;
• maintaining, by the one or more devices, mapping information that indicates current mappings of the customer IP addresses to particular customer resource instances and remappings of the customer IP addresses to particular endpoints on customer networks external to the provider network;
• receiving, by the provider network, packets from client devices, the packets indicating a customer IP address as a destination address and an IP address of the client device as a source address;
• for at least some of the packets, determining, from the mapping information, whether the customer IP address indicated by the destination address of the packet is currently mapped to a customer resource instance on the provider network or is currently remapped to an endpoint on a customer network external to the provider network;
• for a packet for which the customer IP address is currently mapped to a customer resource instance on the provider network, sending the packet to the respective customer resource instance via the provider network;
• and
• for another packet for which the customer IP address is currently remapped to an endpoint on a customer network external to the provider network:
• translating the destination address of the packet to determine a network address of the endpoint on the customer network;
• modifying the packet to indicate the network address of the endpoint on the customer network as a destination address;
• and
• sending the modified packet from the provider network onto a shared network to be routed to the customer network over the shared network.

A non-transitory computer-accessible storage medium storing program instructions computer-executable to implement:

• receiving, on a provider network, a plurality of packets, wherein each packet indicates one of a plurality of public Internet Protocol (IP) addresses assigned to customers of the provider network as customer IP addresses as a destination address and an IP address of a client device as a source address;
• for each received packet, determining an endpoint to which the respective destination address is mapped, wherein the destination address of at least one received packet is mapped to an endpoint on a customer network external to the provider network and the destination address of at least one other received packet is mapped to a resource instance on the provider network that is assigned to a particular customer;
• for each packet for which the destination address is mapped to a resource instance on the provider network, sending the packet to the respective resource instance via the provider network;
• and
• for each packet for which the destination address is mapped to an endpoint on a customer network external to the provider network:
• translating the destination address of the packet to determine a network address of the endpoint on the customer network;
• modifying the packet to indicate the network address of the endpoint on the customer network as a destination address;
• and
• sending the modified packet from the provider network onto an intermediate network to be routed to the customer network over the intermediate network.