I need to submit an online form 6 times, and the submit has to occur all at the same time. I used to do this by having 6 different browsers open at the same time (chrome,firefox,IE,etc), but now the website blocks multiple submissions at the same time when they come from the same IP. So I'd like to have 6 different browsers open, all with a different IP. The important thing is that all the IPs need to be the same speed, otherwise the form submits from the slower IPs will get rejected. How can I do this?