Today, your business relies more heavily on being networked between facilities, data centers, suppliers, business partners and customers than ever before. In fact, some would say that the network IS your business, making your choice of network service technology absolutely critical.

Business Ethernet services are one of the fastest growing wide area network (WAN) communications services because of their flexibility, scalability and cost-effectiveness to address a wide variety of current and emerging applications.

All Ethernet services rely on three fundamental components to deliver basic Ethernet service functionality:

• Ethernet Ports

• Ethernet Connectivity 

• Ethernet Service Bandwidth

Following is a review of each component to provide you with a fundamental understanding of how Ethernet services work.

Ethernet Ports

An Ethernet port, technically referred to as an Ethernet user-to-network interface (UNI), provides the service demarcation point of responsibility between you and the service provider. The UNI type is selected based on the type of Ethernet port your attaching equipment uses, e.g., fiber optic or electrical connection, and the speed of the port.

Some equipment supports multi-rate ports, e.g., 10/100Mbps or 10/100/1000Mbps electrical interfaces, which simplifies the migration to higher speeds as your bandwidth needs increase over time. The significance of the Ethernet port speed you select will depend on your initial bandwidth requirements and your anticipated incremental bandwidth needs for the duration of the service agreement.

Ethernet Connectivity

Ethernet services are available that support two basic types of connectivity – point-to-point (site-to-site) or multi-point (any-to-any). The Metro Ethernet Forum (MEF), the governing Ethernet standards body, has defined the Ethernet virtual connection (EVC) to logically represent these forms of Ethernet connectivity.

The type of Ethernet connectivity you’ll need is closely related to the type of network topology you would like to create and its selection will depend on a number of factors, including:

• Types of applications to be supported

• Application performance requirements

• Number of locations to connect initially and anticipate connecting to over time

• Traffic flow patterns

The most widely deployed Ethernet services use point-to-point connectivity. Multi-site connectivity can be achieved by using a hub-and-spoke or meshed topology of point-to-point EVCs or a multi-point EVC. It is important to understand the differences between each approach to ensure you select the one that best addresses your application requirements.

Ethernet Service Bandwidth

Ethernet service bandwidth defines the amount of traffic you can send to or receive from the network. The service bandwidth can be specified to be the bandwidth of an entire Ethernet port speed or the port speed could be subdivided into the amount of bandwidth needed for a given application. Service bandwidth could also be specified for each service or class of service (CoS).

Ethernet service bandwidth is specified using a committed information rate (CIR). The CIR, specified in Mbps, articulates the amount of service bandwidth that will be subject to the service performance objectives in the product specifications.

Service providers may offer an excess information rate (EIR) or a CIR and EIR for a given service. An EIR-based service (service with no CIR, i.e., CIR=0) is a best-effort service with no assurance that any traffic will get through the network. A service with a CIR and EIR will assure that traffic conformant to the CIR will meet the specifications. Traffic bandwidth that exceeds the CIR is considered excess traffic and is provided no bandwidth assurances; EIR traffic may get through the network if there is no congestion.

For a more in-depth description, as well as insight into advanced Ethernet services options, read the white paper Understanding Business Ethernet Services.