+ 1 Votes Look into Fiber optics stux Updated - 1 year ago At those distances, and since you're running a business, I would strongly consider running fiber. You'd get good speeds and high levels of reliability. There would be no need to set up repeaters, only fiber modems at each end. (Update I am not familiar with brands or vendors. A quick google search list these vendors: http://www.sitech-bitdriver.com/ http://www.focenter.com/foc_about.asp (apparently serves Australia based on your profile) I'd imagine their support can tell you what you'd need for your setup. Your local telecom should also have experience setting up fiber bridges.