Ethernet over Copper, or EoC, leverages one of the primary attributes of T1 lines. That’s their ability to be provisioned over ordinary twisted pair telephone wiring. A T1 lines comes into your facility in the same bundle of installed telephone wire that brings in multi-line telephone service. Because it is ordinary telco wire, most every business location in the country is already wired for service and enabled for T1.
T1 lines use two twisted pair versus one pair for an analog telephone line. One pair is used for the upstream connection. The other is used for the downstream connection. This gives you 1.5 Mbps in both directions at the same time, also called full duplex operation. T1 line prices have come down to several hundred dollars per month, although that number varies with location.
For about the same money you can get Ethernet over Copper bandwidth. But your Ethernet link will be running at 3 Mbps rather than 1.5 Mbps. Why the difference? It’s a matter of more efficient modulation technology. T1 was designed by the phone companies right after WWII to transport telephone calls digitally. Thus, it was designed as a synchronized system subdivided into 24 precise channels. It’s a great match for loading phone lines onto a digital trunk, but bears no resemblance to today’s network protocols. Ethernet is based on packets, not channels, and doesn’t need the T1 system for transport. In fact, it takes a protocol conversion to go back and forth from T1 to Ethernet.
T1 lines can compete with Ethernet over Copper by using more lines to increase bandwidth. Add another 2 pair for an additional T1 line and you can double your bandwidth from 1.5 Mbps to 3 Mbps. The process used to couple multiple T1 lines to create one effectively larger line is called bonding. As you might expect, Ethernet over Copper lines can also be bonded to create a larger bandwidth connection. T1 line bonding is practical up to 10 or 12 Mbps. EoC bonding can deliver bandwidths as high as 100 Mbps over very short distances. Standard Ethernet network speed of 10 Mbps is readily available. You can also get 15 or 20 Mbps service without too much trouble. Once bandwidth gets above 45 to 50 Mbps, it generally makes sense to move up to fiber optic connections.
The one rub with Ethernet over Copper technology is that it is distance limited. That’s why EoC is often called a Metro Ethernet service. You’ll find it readily available in major metropolitan areas, but not farther out in sparsely populated areas. EoC delivery is generally limited to a few miles from the central office where the termination equipment is installed. For higher bandwidths, it’s only a matter of blocks away from the nearest point of presence. Downtown that’s no concern because of the concentration of both users and service provider facilities.
T1, on the other hand, has no distance limitation. It was designed from the beginning to have regenerators placed every mile or so in the line to restore the signal to a perfect wave shape. Longer spans require more engineering and construction effort, so cost goes up. Even so, you can get T1 service from coast to coast if you like. Actually, the T1 line is only carried by copper to the nearest telco central office. From there it rides on a fiber optic network to the central office nearest the far location and is then delivered on copper wiring.
Business bandwidth demands are increasing faster than fiber is being trenched to every business. That doesn’t mean you are stuck with a basic 1.5 Mbps of service when you really need 10 or 20 Mbps. Find out what’s available for your business location and compare prices for Ethernet over Copper vs Bonded T1 services now.
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