Ethernet over Copper (EoC) Gains Market Traction as Telcos Delay Build Out of Fiber to Commercial Buildings

Ethernet over Copper (EoC) technology is rapidly taking over market share from T1, bonded (n x) T1 and T3 private line circuits.   Service areas are expanding with EoC now available throughout most of the U.S.  EOC is often referred to a “Mid Band Ethernet” to denote a speed from 2Mbps to 100Mbps.

EoC is simply the transport of the IEEE 802.3 Ethernet MAC frame over one or bonded (n x) DSL for the “first/last mile”  between the customer premises and the service providers Point of Presence (POP).  It’s the same copper twisted pairs used for PSTN voice/fax communications and for high speed Internet access offered by most telcos.  For example, 10Mbps EoC uses five such DSL copper pairs between end points. EoC is typically available at 2M, 3M, 4.5M, 5M, 6M, 10M, 15M, 20M bps  speeds.

Why copper?  Because fiber to commercial buildings is still not widely available in the U.S.  According to Vertical Systems Group, fiber access deployment is currently limited to only 11.7% of buildings with more than 20 employees.  What about the other 88.3% of business sites where fiber is not available?  They are all candidates for EoC services. 

EoC pricing is much lower than that of bonded T1 (4 wire) circuits, and it is much easier to upgrade by adding additional copper pairs than conditioned 4 wire T1 circuits.  For example, an upgrade from 2Mbps to 10Mbps can be deployed a lot quicker and cheaper than n x T1 or fractional T3.  A 3Mbps Ethernet over Copper circuit can cost as little as $ 150 per month, while a 10M bps EoC private line can be as low as $400 per month (reference: EoC provider’s pricing guide).

Of course, pricing for the circuit depends on the end to end distance between EoC end points.  If it’s an inter-city connection, then the carrier’s fiber backbone will likely be used to transport the end to end Ethernet MAC frame, with copper (DSL) used for the first and last mile.  That first/last mile maximum distance depends on the reach of the DSL deployed (e.g. SHDSL, VDSL, or VDSL2) by the provider.  In some cases EoC repeaters/extenders can be used to increase the first/last mile distance between the customer premises and the provider’s CO/POP.

EoC is commonly used as a point- to- point private line service between two business locations.  However, it can also be offered as part of a virtual private line (e.g. Frame Relay replacement, with multiple destination end points) or a virtual private LAN (any location- to- any location connectivity). In those cases, the EoC circuit is terminated in the EoC service provider’s central office (CO) and switched to the destination end point, based on the destination Ethernet MAC address.  In the case of private line EoC service, the end to end circuit is hard-wired (“nailed up”) within the provider’s CO at subscription time.

EoC was originally part of the IEEE 802.3ah Ethernet First Mile (EFM) standard, which was finished in early 2003 and approved by the IEEE Standards Board in 2004. That standard includes “Ethernet access OAM” which can be used to help diagnose problems.  Current EoC implementations can use any type of symmertic DSL (rather than the SHDSL specified in the EFM standard).

Note that “Carrier Ethernet” over fiber is also specified by the IEEE 802.3ah standard.  Either one or two fibers can be used to transport 1G Ethernet over Single Mode Fiber (SMF). Of course, lower speeds from say from 100 M bit/sec can also use the 1G Ethernet by simply padding idle characters to reach 1G bit/sec.

Today, EoC is available in many areas of the USA, with XO Communications being one of the leading service providers focused exclusively on business customers. XO currently offers the various types of EoC services at speeds up to 100M bps.   They also offer Ethernet over Fiber.

An overview of XO’s Business Ethernet Services is at:


For more information on XO’s EoC and other carrier class services for business customers please contact:

Mike Weiss
XO Communications Sales Executive