Virtual MAC address? I think you mean "virtual IP addresses". See
man 5 interfaces, and follow the documentation links at the very end. On my system, it says:
For advice on configuring this package read the Network Configuration chapter of the Debian Reference manual, available at http://www.debian.org/doc/manuals/debian-reference/ch05.en.html or in the
Examples of how to set up interfaces can be found in
But, even if you assign extra IP addresses, your traffic is still going in/out of your system through the SAME NIC. No matter how many IPs, only 1 NIC. No speedup. Multiple IP addresses are good for obfuscation, virtual machines, and simulated network testing.
Read and enjoy!