Global-scale connectivity using scalable virtual traffic hubs

A system, comprising:

• one or more computing devices;
• wherein the one or more computing devices include instructions that upon execution on or across the one or more computing devices cause the one or more computing devices to:
• create, using one or more cloud resources, a hub for network connectivity between a plurality of networks including a first virtual network and a second virtual network;
• configure, in response to one or more programmatic requests, at least a portion of a route table to be used at the hub for traffic flowing between the first virtual network and the second virtual network;
• and
• transmit, via the hub in accordance with the route table, one or more network packets from the first virtual network to the second virtual network.

One or more non-transitory computer-accessible storage media storing program instructions that when executed on or across one or more processors cause the one or more processors to:

• configure, using one or more cloud resources, a hub for network connectivity between a plurality of networks including at least a first virtual network and a second network;
• create, in response to one or more programmatic requests, a route table to be used at the hub for traffic flowing between the first virtual network and the second network;
• and
• transmit, via the hub in accordance with the route table, one or more network packets from the first virtual network to the second network.