Ethernet Over Copper: The Perfect Pair

By Doug Allen

Maybe its something in the name. Ethernet over copper (EoC) solutions have been around for more than five years, but one can still find a lingering perception that the technology is a bit of a misnomer. Why run Ethernet, a broadband protocol, over ubiquitous but seemingly antiquated, narrow-band copper?

The answer is, this isnt your fathers copper service. With the advent of bonding technologies that combine two or more twisted pairs, total bandwidth available has gone up dramatically, and the implementation advantages of Ethernet have combined to create a perfect storm of midband access alternatives. Once EoC establishes a name for itself, with the same kinds of performance guarantees that its TDM brethren enjoy, look out! Providers and agents can market and sell, essentially, T1s on steroids and layer a host of value-added services on top of a much fatter access pipe, increasing their addressable market while upselling a broader services menu over a single link.

Ethernet has taken off in the access, or first-mile, space for the same reasons its dominated the LAN for decades. EoC offers more bandwidth for the customers buck, drastically undercutting TDM access prices, and it provides a familiar handoff to the customers CPE, eliminating the complexity of IP or T1/SONET interfaces. As a native Ethernet solution, theres no need for an underlying Layer 2 WAN circuit. Provisioning and deployment are much simpler and the service itself affords greater visibility into the network, making it easier to manage. And if all that isnt enough, circuit installation time is often as little as two weeks, whereas a T1 can take months to turn up.

Ethernet is also available in relatively granular bandwidth increments, so customers can increase their capacity as well as the number of services that run over the pipe fairly easily. Actually, EoC offers the most flexible midrange capacity options around, even if bandwidth-on-demand functionality is rare. This is partly because EoC comes in several flavors: EoC over DSL, EoC over NxT1 and/or DS3/NxDS3 and, finally, simple EoC. Among these, bonded circuit speeds generally range from 2 to 3mbps of symmetrical bandwidth (for Ethernet over SDSL), up to 12mbps over DS1 and 35mbps for DS3 and from 2mbps to 30mbps for standard EoC. Some providers use additional bonding to further increase these rates, too.

And for that kind of capacity, the price points cant be beat. According to agent ARGs Kristine Palatucci, director of solutions engineering, EoC generally costs about 15-40 percent less than NxT1 or Ethernet over fiber in the most common service segment, those that run about 3 to 10mbps.

Roopashree Honnachari, senior industry analyst, business communication services at research firm Frost & Sullivan, breaks it down like this: Right now, EoC has to only to be compared to T1s if earlier you got 1.5mbps for $400 per month, now [with EoC] you get 5mbps for $600, as compared to bundling two T1s and [paying] $800. The price per mbps is no longer increasing linearly thats the benefit you are looking at.

And EoC has a potentially huge target market. Customers that need more than a T1 or two of access capacity, but lack fiber (about 81 percent of all U.S. business sites) are perfect candidates for a solution thats just as reliable as TDM access, but easier and quicker to deploy, especially in rural or remote areas. EoC also makes sense when the cost to build out fiber access spans to the customer is just too high or provisioning an alternative circuit would take months, not weeks.

Whats the catch? The big drawback for EoC is its distance-sensitive, meaning the signal-to-noise ratio and thus, capacity deteriorates beyond a certain point from the providers central office. Just as standard 100mbps Ethernet (CAT5) only works well for about 100 meters, full-throttle EoC is best suited to those locations typically 10,000 to 12,000 feet from the central office, depending on the speeds desired; the higher the rate, the shorter the distance supported. The distance and capacity can be extended somewhat by bonding additional pairs of copper, but most provider offers still top out at roughly this limit before performance degrades. The other caveat though more easily dealt with is that EoC requires dedicated head-end switches to be configured as necessary for distance and capacity requirements at the central office, which typically can take up to two weeks (including time to provision the links). The exception is EoDS1, which bonds standard T1 circuits from the carriers central office to the customer site.

For fiber-less customers whove outgrown T1 rates, then, EoC is an ideal fit, perfect for SMBs within 10,000 feet of the providers wiring center.

And EoC has seen significant progress over the last few years. Vendors big and small have gotten into the market, ranging from startup Hatteras Multi-Service Delivery Platform, to more established players like Cisco Systems Inc.,  Juniper Networks  and Alcatel-Lucent.  Carrier-neutral Ethernet exchanges or peering points have begun to spring up, and major U.S. providers are piling up their own Ethernet network interface and access agreements to broaden their service reach.

On the provider side, EoC offerings similarly run the gamut from smaller, pure-play providers to the large carriers. The high-profile list includes AT&T Inc., XO Communications Inc., Qwest Communications International Inc., Verizon Business,  Intellifiber Networks, US Signal and Integra Telecom Inc., as well as a number of providers operating at the city or metro level.

While sizing the space remains difficult, Frost & Sullivans Honnachari reports double-digit growth across the board for these U.S.-based offerings.

Some notable examples of national offerings: last April Covad Communications launched a mid-band EoDS1/NxDS1 service across its national footprint, offering 1 to 5mbps for a somewhat pricey $259 to $859 per month (depending on capacity and length of contract. But given their network footprint and broad access to quality copper plant, the service should find fans, according to Brian Washburn, research director at Current Analysis Inc., among end-users and resellers. Covad uses VLANs to logically separate multiple services over the same circuit to improve capacity usage. 

And Qwest followed suit the following month, becoming the first of the Big Three U.S. telcos to introduce a national equivalent service featuring private line and point-to-point VPLS, though it has not fully integrated the offering with its metro optical Ethernet backbone for long-haul transmission yet. Similarly, in addition to these two providers, AT&T and XO also have released EoC services that bond copper pairs and use DSL to carry Ethernet from 10 to 30mbps and beyond in some cases.

To be fair, several MSOs have jumped into the EoC game too, such as tw telecom inc.,  which unveiled its own EoDS1/NxDS1 service back in 2006. But as a general rule, these cable operators are only coaxing out top rates of about 3mbps from their hybrid fiber/coax (HFC) plant and can start as low as 512kbps. Time Warner Cable Business Class (TWCBC) and Cox Business also have gone to market with EoC, emphasizing the ability to connect smaller branch offices that rely on cable access in the same market. A sample list price point of TWCBCs Ethernet over HFC is $269.95 per month; these services are sold with a single Ethernet virtual channel to attach securely to customers corporate networks without touching the HFC networks IP layer, said Washburn.

Carrier Services. EoC services already are beginning to mature. For starters, most carriers can carry Ethernet traffic natively between metros, or even long-haul in some cases, feeding Ethernet links to a central switching fabric that runs over an IP MPLS core. Such far-flung WAN connectivity is a relatively new phenomenon for Ethernet services, which for years were limited to intra-metro connectivity. By extending the WAN, EoC is well-suited to both SMBs looking to connect a few sites and the enterprise with business locations of all sizes.
 
The two primary applications for EoC access are still IP MPLS interconnection and VPLS. Though VPLS is certainly available over EoC, these Layer 2 VPNs are still an emerging technology, and so far the demand is limited to large, well-distributed enterprises with access to fiber, according to analyst Honnachari.

So far, one of the main drivers for Ethernet (over fiber or copper) is its ability to carry multiple applications or services over a single circuit, usually separated logically by VLANs, thus reducing the number of access lines needed. Consequently, most EoC providers simply see Ethernet as a bigger pipe to carry the important stuff value-added applications. For instance, XO offers its IP Flex VoIP service, VPLS and MPLS IP VPN, not to mention the more commoditized DIA, over a wide range of EoC options, including EoC DS1/NxDS1, at rates of 3, 5, 10, 15 and 20mbps, and up to 40 and 88mbps for multiple bonded DS3s (as is common, XO bonds two DS1s/T1s to get its baseline bandwidth of 3mbps over EoC). Another new service, Ethernet over bonded SDSL, bonds G.SHDSL pairs to deliver 2 to 3mbps, to address the lower end of the market.

Customers can increase their bandwidth in granular increments, but not on demand; theres a typical waiting period of two weeks while the provider re-configures their CO head-end and adds the designated number of copper pairs to the access link.

Or take MegaPath/Covad/Speakeasy, whose merger is still pending. It offers EoC from 3 to 20mbps, enabling similar applications (IP MPLS access, VoIP) as well as MegaPath Managed Security, a Web security, monitoring and support package. Its most popular EoC offering, executives said, is MegaPath Duet, an integrated voice and data service.

US Signal takes a similar managed service approach, enabling multiple options over the same line such as Virtual Ethernet Services, a point-to-point or point-to-multipoint VPLS offering with built-in QoS, as well as MPLS and Internet access, up to 20mbps. Notably, the provider monitors all circuits with proactive alarming as part of its CPE management chores.

Cavalier Telephone doubles that speed range, from 3 to 40mbps, depending on the type of EoC used, and stresses their services granular and cost-effective bandwidth increments, enabling customers to bundle DIA, integrated access, hosted PBX (IPeer), IP MPLS VPNs, VPLS and Ethernet private line services in any combination. Serving more than 100,000 commercial buildings throughout its Mid-Atlantic and Midwest footprint, Cavalier finds a majority of its customers up to 12,000 feet from the CO, which represents the vast majority of customers in most urban and suburban markets, said Alex Foster, product manager, data services, at Cavalier.

Some of these providers have built-in ways to maintain the proper signal-to-noise ratio needed to maintain throughput as the customer link starts to exceed its bandwidth/distance limits. US Signal automatically down-rates the lines bandwidth as needed when the distance becomes too great to achieve the desired capacity, and then bonds additional circuits as needed. XO typically provides more loops than are technically required for a given speed-to-distance ratio. This gives us a greater flexibility at installation, provides for a greater customer experience and allows us to provide the expected speeds even when copper facilities are less than ideal, said Mark Saffell, director of product management, data solutions, at XO.

Sales Secrets. With such a compelling service, it may surprise you to hear that so far, agents and channel partners have a somewhat mixed record when it comes to selling EoC services. EoC success is very unevenly distributed, said Foster. Some channel partners have not fully embraced the technology or have not altered their cold calling to focus on EoC-rich areas. Other partners view EoC as a core part of their strategy and really bring a strong analytical mindset to bear, focusing on both the areas and verticals best served by EoC. We think channel partners will find the most traction in the professional services vertical, as these users have a need for bandwidth well over T1 levels, and they demand reliability as they have a high hourly cost for both downtime and idle waiting time. Some applications can help drive EoC as well midsized disaster recovery projects are a great example.

Part of the problem may simply be lack of customer awareness. Customers dont usually come to us requesting EoC they are usually asking for either more bandwidth or if they have fiber options available, said ARGs Palatucci. Once we explain the technology and associate it with a cost we dont usually have an issue selling the right fit, regardless of the delivery method.

Sluggish sales may also be due in part to less price-sensitive customers who are emotionally tied to their legacy technologies, as S.L. Sweet, director of product management for MegaPath, put it. In cases like these, Sweet recommends emphasizing the lower total costs of ownership with EoC, contrasting a fully managed, multiple-service solution to an on-site implementation.

From our perspective, our partners have totally embraced services delivered using Ethernet over copper technology, said XOs Saffell. From an access perspective, our EoC footprint combined with our ability to bundle VoIP and WAN solutions on top of it gives our partners a great value proposition. We see a lot of success using it to deliver Dedicated Internet Access, VoIP and MPLS-based WAN services.

Nevertheless, providers do see a greater need for agents and channel partners to educate their customers on the availability and advantages of EoC, particularly in terms of its impact on network architecture. In the world of EoC, a location that was previously a small T1 branch may turn out to be an ideal location to deploy a backup and replication server environment or a new gateway to the Internet, said Cavaliers Foster. For agents that want to make a substantial play in the managed services space, VPLS networking over EoC can allow an agent to create a single interconnect (NNI) and securely haul traffic from a number of different customers back to that location to provide advanced hosted services. Agents that want to provide a clean pipe to the Internet or a hosted desktop solution can really take advantage of both the high bandwidth and Ethernet networking capabilities offered by EoC.

For agents and partners, the initial sales process includes business case definition, vendor and solution evaluation, configuration support and on-site sales assistance. As Foster mentioned, EoC can open up new applications to customers that were once constrained by a T1 or fractional DS3, such as in-store digital signage, synchronous replication and video. Once the solution is in place, support chores shift to order management throughout the installation and billing process, training and enabling moves, adds and changes. However, the level of partner or agent support can vary depending on their status with the provider; with MegaPath, Advantage Partners cede provisioning, billing and support back to the provider, but a MegaPath Reseller owns the full whole customer relationship.

Setting appropriate customer expectations for EoC is critical. Agents should work with their provider partner to pre-qualify each business site as part of the initial consulting process; usually some form of Ethernet access is available, if distance limitations rule out EoC. Prospects that are currently making due with two bonded T1s frequently take a look at our EoC solution and want to jump to 10 or 15mbps and this isnt always possible because of the distance limitations, said Foster. It is important to set expectations realistically. In fiber-rich markets the old [copper] plant concern can be stronger but given that fiber is available to such a small fraction of businesses it is rarely a factor.

It helps to understand the sweet spot for EoC in terms of the distance vs. speed ratio, in relation to price, that determines a successful implementation. It comes down to feet, speed and number of pairs used, said MegaPaths Sweet. So, for 5mbps (a sweet spot), you can be 11,000 feet from a central office, if four pairs of copper are pulled. To get out to 14,000 feet, you would need to double that to eight pairs, which increases the underlying costs. So 5mbps on four pairs at 11,000 feet is a good solid target.

In addition, agents can explain the technology options available in a provider-independent fashion, clarifying the difference between EoC, Ethernet over fiber and a managed Ethernet handoff. Then theres the issue of choosing the right provider. Some carriers are simply reselling anothers EoC service, said ARGs Palatucci. Some deliver more copper pairs than are required which offers a level of back-up. Having a thorough understanding of the product and the equipment associated with it also helps us troubleshoot and get to issue resolution for our customers in a more timely fashion.

For instance, in case of an outage or degraded performance, ARG will work with the customer to check their CPE (a Hatteras switch) and copper link status, run ping sessions and trace routes to identify the source of network bottlenecks and, if necessary, dispatch test equipment to the customer site.

Redundancy is also a key concern, especially for those customers replacing highly reliable T1 connections. Some providers use SONET or Resilient Packet Ring for protection from the CO to the network core and provision extra access loops with N+1 redundancy to safeguard the access link until it hits the CO. The underlying delivery technology leased line, cable HFC or xDSL can also impact reliability, whether the service is shared or dedicated.

Provider partners and agents can differentiate on a number of value-adds as well, such as guaranteed prompt deployment, configuring and provisioning a solution in (typically) two weeks, proactive CPE monitoring and management, a dedicated project manager to oversee implementation, troubleshooting, and project resolution and a customer portal that tracks customer utilization, service quality metrics, and traffic profiles and trends.

Finally, SLAs are crucial, since in most cases EoC access will replace the venerable, tried-and-true T1, whose reputation is built on maximum uptime and rock-solid performance guarantees. This has been a sore point for EoC customers in the past. Although performance quality always will be suspect once traffic goes off-net at least until Ethernet exchanges and NNI agreements prove themselves over time customers need to see T1-like SLA levels that cover installation, availability, mean time to repair and latency guarantees. Jitter is another key requirement for higher-capacity links that run video. For example, Covads SLAs for all its Ethernet offerings, include [an] installation interval with a service credit of 50 percent of one months recurring charge (MRC), availability of 99.99 percent with a service credit of 3 percent of the (MRC) per hour, mean time to repair with a credit of 10 percent MRC, and delay and delivery SLAs with service credits up to 10 percent of MRC, according to Cindy Whelan, principal analyst at Current Analysis.