The Case for Carrier Ethernet

Carrier Ethernet is necessary, given our local, continental and global connectivity. Last night I was at a baseball game, and saw people chronically on their cell phones and one even reading a Kindle. Meanwhile, digital signage displayed the player at bat and all his personal statistics. Clearly there was no interruption of services at the stadium!  Carrier Ethernet’s promise is to ensure that all services, no matter the type, will be consistently delivered. Just think, it wasn’t that many years ago we got used to the familiar tune of a modem dial-up and then waited…and waited. Today, that is not tolerated. We expect fast service, guaranteed Internet connectivity, no dropped phone calls, email delivery, streaming video…you get the idea.

Some of the challenge is that ISPs and Operators understand this, but have faced a number of conditions, such as what type of equipment to invest in that will support their requirements of a more efficient network, how easy the equipment should be for ease of deployment and troubleshooting, and of course, associated costs—not to mention whether the equipment is compatible to other network devices.

Ethernet Protocol
In the early stages of (LAN) networking, a number of different technologies were employed for connections to the outside world. Small businesses typically used a variety of DSL technology, ISDN and cable modems. But larger businesses relied on leased lines, ie, T1 or E1, based on the public telephone companies’ infrastructure. As the leased line technology faded due to the limitations of supporting higher bandwidth, Sonet and SDH emerged….but they were often expensive and posed other challenges.

While Sonet/SDH pushed fiber-based deployment, a big step in network cabling options, folks looked to the Ethernet protocol as the protocol of choice due to its flexibility; plus, it utilized an existing cabling infrastructure. Businesses needed more bandwidth, low latency, and yet the capability to support cloud-based services, voice/video/data services and remote VPNs, for example. Thus, Metro Ethernet: a technology supporting up to 10 Gigabit (100 Gigabit in the future) and distances of up to 130Km over fiber, while the copper interfaces support up to the standard TIA/EIA 100m, evolved as the new standard.

Not only did Ethernet become the common choice for LANs/WANs, but it has recently been deployed for residential networks as well. The Ethernet protocol, however, is based on “best-effort” service. That is not the same as “guaranteed service”. This is where Carrier Ethernet becomes important, and the Metro Ethernet Forum took on the mighty task of organizing and defining standards to ensure networks world-wide will attain peak performance.

Metro Ethernet Forum (MEF)
The Metro Ethernet Forum (MEF) is a defining body for Carrier Ethernet (CE), comprising of more than 150 organizations, including telecommunications, service providers, Cable companies, network/equipment manufacturers, semiconductor vendors, and testing organizations. The MEF rolled out CE 1.0, which specified the standardized way Carrier Ethernet should be implemented. CE 2.0 rolled out more standards, plus allowed for multiple classes of service (COS), with managed and interconnected characteristics. There are five attributes for Carrier Ethernet: standardized services, scalability, reliability, QoS, and service management.

The Attributes

Standardized services: universal service provided globally and locally via standardized equipment; supporting point to point and multipoint to multipoint services, suited for voice, video and data networks

Scalability: supports a bandwidth from 1Mbps to 10Gbps and beyond; spans a wide variety of physical infrastructures already implemented by Service Providers; allows unlimited number of users to access network services

Reliability: provide the capability for rapid recovery time when faults occur on the network; detect and recover from faults without impacting users

Quality of Service: wide choice of bandwidth granularity and QoS options; Service Level Agreements (SLA) that deliver end to end performance for voice, video and data over business and residential networks. SLA addresses performance based on frame delivery, loss and delay characteristics

Service Management: the ability to monitor, diagnose and centrally manage a network; Carrier class OAM (Operations, Administration and Maintenance), and rapid service deployment

One of the key features among the standards is a better way to handle bandwidth utilization, where different classes of service can be assigned priorities, which are maintained across the various stages of the connections. This is so important, as WANs are transmitting data over different networks that they may not own and yet are expected to support how reliably data is transferring from point A to point B. Large metropolitan areas may have the same carrier from point to point, but what about when you are sending information through small local ISPs or across to a different continent?

Furthermore, the type of equipment supporting network traffic has evolved, to support the CE 2.0 standards. Network Interface Devices (NIDs) are typically owned by the Service Provider but often reside at the customer premises (CPE) where the carrier network ends and the customer network begins. This is the demarcation line which determines who is responsible for installation, maintenance, service level agreements (SLA), and traffic management. The intent is to reduce truck rolls, by using equipment that can identify where a fault has occurred, and quickly resolve it remotely. And just as important, certified equipment supports cross-manufacturer compatibility.

Conclusion
In the interest of faster and more consistent rollout of MEF services for Carrier Ethernet, many Service Providers are now requiring Network Interface Device (NIDs) to be CE 2.0 certified. By investing in certified equipment, it reduces the amount of time required for bench testing before deployment. Some Service Providers are interested in certifying their entire network, to ensure an excellent customer experience. Certified Professionals can assist the Service Providers and Operators in designing or supporting a Carrier Ethernet network. CE 2.0 really includes CE 2.0 certified equipment, certified Service Provider networks and certified professionals.