Network architecture for cloud computing environments

A system comprising:

• data processing hardware of a public-cloud computing environment;
• and
• memory hardware in communication with the data processing hardware, the memory hardware storing instructions that when executed on the data processing hardware cause the data processing hardware to perform operations comprising:
• receiving, from a first virtual machine (VM) of a first private-cloud computing environment, via a network tunnel established between the first private-cloud computing environment and the public-cloud computing environment, a first packet comprising:
• a source address comprising a first private IP address of the first VM;
• and
• a destination address comprising a second private IP address of a second VM of a second private-cloud computing environment;
• translating, using a network address translation (NAT) mapping at a private virtual network of the public-cloud computing environment, the source address of the first packet from the first private IP address of the first VM to a third private IP address of a third VM of the public-cloud computing environment;
• sending the first packet to the second private IP address of the second VM of the second private-cloud computing environment;
• receiving, from the second VM of the second private-cloud computing environment, a second packet to be sent to the first VM of the first private-cloud computing environment, the second packet comprising a destination address comprising the third private IP address of the third VM;
• translating, using the NAT mapping at the private virtual network of the public-cloud computing environment, the destination address of the second packet from the third private IP address of the third VM to the first private IP address of the first VM corresponding to an actual destination of the second packet;
• and
• sending the second packet to the first private IP address of the first VM of the first private-cloud computing environment.