For benchmarking loopback connections, addressing really shouldn&#x27;t be an issue, as you have an entire &#x2F;8-subnet to split between your client(s) and server(s) (127.0.0.0&#x2F;8). You would need some logic to set up eg 10.000 listening servers, and 1000.000 clients to get it working, and at some point you&#x27;d probably run into memory or other limits.<p>I&#x27;m a little surprised some simple googling didn&#x27;t turn up any examples of this - I&#x27;m sure someone have tried it out in order to do some benchmarking of high-performance network servers&#x2F;services?<p>Apparently ipv6 changes this to a single (loopback) address, but then again, with ipv6 you can use entire subnets per network card.