If this were just for LAN connections you might wonder what all the excitement is. After all, Cat-6 wiring is good for Gigabit Ethernet. But this isn't about runs from your desk to the closest switch. It's about connecting your company to a broadband service provider. You know, underground - down the street - up the utility pole - in the building. Yes, that kind of connection. Generically, they're called WAN access connections. WAN, standing for Wide Area Network, to distinguish it from LAN for Local Area Network.
Why is WAN access bandwidth using hundred year old copper transmission technology so important? Many businesses have a crying need for more bandwidth to support everything from server farms to employee Internet access to data transfer between business locations. The coming push for electronic medical records is only going to exacerbate that when every medical center, hospital and doctor's office will need to rapidly transfer high resolution medical images as well as general documentation.
But why copper? Actually, fiber optic transmission stands ready to go with almost unlimited bandwidth. There's just one small problem. Getting new fiber installed from place to place is really expensive. Copper... Not so much. One reason copper is so cheap is that it's already in place. After 100 years, just about every location that needs to be connected already is. So if you can find a way to hot rod the copper pair wiring trunks that you already have, then you have a relatively inexpensively way to increase you bandwidth.
This is exactly what Ericsson is up to. But instead of trying to shove higher frequency signals down a single twisted pair of phone wire, they're taking a more sophisticated approach of pressing multiple pairs into service. With 6 copper pair, Ericsson has demonstrated 500 Mbps service over 500 meters. That's not going to get you across town, but it might well get you to a nearby building that is already wired for fiber or to a FTTC (Fiber to the Curb) box that serves a neighborhood.
Ethernet over copper isn't a brand new technology. In fact, it is deployed now in metro areas to expand a carrier's service footprint beyond their installed fiber POPs (Points of Presence). The techniques that are used are similar to what Ericsson is employing, including multiple pair transmission and MIMO (Multiple Input Multiple Output) analysis to counteract the effect of interference and signal reflections. Remember that if a business has 6 pair of incoming phone wires they are probably bundled together in a binder cable where they can potentially crosstalk.
Ericsson is pushing the technology beyond the 50 to 100 Mbps service levels that are possible with existing installations and expects its equipment to be available by year end. Right now you can get DS3 level Ethernet over Copper service at 45 Mbps up to a couple of miles from the nearest carrier POP. If you're hurting for bandwidth and can't afford the capital expenditures for fiber optic service, copper transmission service might be the perfect answer.
