The ST-series enables wide area Ethernet service, also called Ethernet Private Line (EPL), with the exceptional levels of performance and flexibility required to make EPL a viable WAN service offering. Most importantly, the ST-series uses a combination of advanced technologies to enable EPL service with the same Quality of Service (QoS) as ATM and Frame Relay technology.

The Appeal of Wide Area Ethernet

Ethernet Private Line service offers a number of advantages to both corporate customers and service providers. For corporations, the extension of Ethernet through the WAN leverages investment in existing Ethernet equipment, offering a low-cost alternative to ATM and Frame Relay service. Ethernet can be offered in more granular fashion than ATM or Frame Relay, so customers are not forced into major bandwidth upgrades when they only want an incremental addition. Also, Ethernet Private Line can be "turned on" in software, dramatically reducing the time and cost typically associated with private line service provisioning.

For service providers, EPL introduces a substantial new revenue opportunity as well as cost savings. Ethernet Private Line is offered over existing IP/MPLS networks, leveraging available IP capacity. The ease with which the service can be provisioned also benefits service providers, since they can more quickly offer service to customers with lower start-up costs.

ECI enables EPL services through its Multi-service over MPLS implementation (also called Layer 2 transport over MPLS). Multi-service over MPLS allows service providers to offer data services including Ethernet, Frame Relay and ATM onto a converged IP/MPLS backbone. ECI is a pioneer in Multi-service over MPLS deployment, introducing the first commercial implementation based on IETF Draft Martini (co-authored by ECI technical leaders in September 2001). Multi-service over MPLS enables a wide range of profitable services beyond the capacity of the existing data service backbones, while reducing cost and complexity.

Benefits of Ethernet Private Line Service

Layer 2 Simplicity with Layer 3 Intelligence: The ability to transport Layer 2 Ethernet traffic over the IP/MPLS backbone enables service providers to make the most of Ethernet's simplicity and low cost while maintaining circuit-oriented intelligence. This intelligence provides Quality of Service, constraint-based routing, traffic engineering, mesh protection, fast restoration, policing, prioritization and service-level management. Service providers can plan any mesh or loop architecture that easily evolves without reconsidering the entire network design.

Virtual LAN (VLAN) Scalability: MPLS addresses the critical scaling limitation resulting from the system-wide limit of 4,096 802.1Q Ethernet VLANs while transparently maintaining 802.1Q interoperability. By replacing 802.1Q tags with MPLS labels, the number of unique identifiers is expanded to more than one million per device. Furthermore, 802.1Q tags become locally significant, allowing tag reuse at the network edge.

Service Creation at the Edge: Traditional data service provisioning models require a service provider to maintain connection state throughout the core network. In contrast, with Layer 2 services over MPLS, Ethernet connection state is maintained only at the edge of the network, with service creation at the edge and service transparency at the core. That significantly reduces administrative complexity.

ST-series Ethernet Private Line Advantages

The ST-series provides the features required to offer advanced Ethernet services, including:

Any-to-Any Service Interworking: The ST-series supports interworking between ATM, Frame Relay and Ethernet services. Much like Frame Relay/ATM interworking, any-to-any service interworking enables Ethernet-connected customer sites to be connected to ATM and Frame Relay-connected sites.

Sophisticated Quality of Service: The ST-series provides sophisticated QoS and traffic management capabilities for Ethernet traffic, enabling each customer's traffic to be managed independently with dedicated software-configurable traffic policers, queues and schedulers. Only ECI's solution can precisely match the high levels of QoS previously only associated with traditional ATM and Frame Relay switches.

Automated Service Management: Provisioning and management of Ethernet services is dramatically simplified via the ShadeTree Management Suite, a powerful, API-based provisioning and element management system. Operators can easily create and manage Ethernet Private Line services, dramatically reducing the time required to provision new services while preventing costly configuration errors. To provision services, operators simply select an interface, service type and class, and then assign a service name.

Advanced Ethernet Capabilities: ST200 Gigabit Ethernet PHY cards provide the following advanced Ethernet over MPLS capabilities:

· VLAN switching

· 802.1p <-> MPLS EXP mapping

· 4,096 distinct VLANs per port - an order of magnitude greater than most Ethernet switches, which typically support a maximum of 1,024 or 4,096 VLANs per system

· Per-VLAN policing and shaping

ST-series Ethernet Applications

Virtual Private Line Service: EPL, as enabled by ECI, is a virtual private line service, thus allowing very flexible service level agreements based on actual customer usage rather than physical access bandwidth. With the ST-series, class of service offerings and guaranteed service levels can be supported with the same QoS as ATM or Frame Relay service.

Internet Access: The ST-series is an Internet-class router, and can support the addition of Internet access over the same physical access link as the Ethernet Private Line. Separate VLAN IDs are used to identify which traffic is destined for the private site and which traffic needs to be routed over the Internet.

Ethernet Access to MPLS IP VPNs: This is a compelling customer application, due to the level of flexibility it offers for connecting corporate sites to MPLS IP VPN service. With the ST-series's Any-to-Any service interworking, sites with metro-Ethernet services can connect to the WAN via secure IP VPN service.

Wide Area Video Distribution over Ethernet: Previously, the strict QoS required for wide area video transport prohibited the use of an Ethernet WAN. With the sophisticated QoS of the ST-series, customers are now taking advantage of the ability to use lower-cost Ethernet connectivity for wide area video distribution.

Backhaul to Data Center: Backhaul to a data center, or a centralized network-based application server, is similar to Internet access in that it is a multipoint-to-point service. It differs in that often this type of connectivity requires the guaranteed service provided by the ST-series. For network administrators, this service enables a dedicated Ethernet connection from their site to the data center, providing a "virtual onsite data center"

Inter-Metro/Inter-LATA Connectivity: This application is a regional (i.e., Boston - NY - Washington) long haul data service that offers customers flexible Ethernet access interfaces (10/100/1000 with or without VLANs) for a point-to-point service with service level guarantees.

Hub-to-Hub Interconnect: EPL can enable cost-saving private connections within the carrier's own network to connect together data centers and other central, but replicated services hubs.

Private Peering: ISPs enter into peering arrangements, whereby they agree to carry each other's traffic (provided it is at a similar volume) at no cost. Typically, peering occurs via public peering facilities, which require ISPs to purchase circuits at these locations. Using the ST-series, ISPs can establish direct peering relationships by constructing EPL private peering connections with other carriers with whom they have negotiated reciprocal traffic agreements. This avoids the expense of continuous access charges associated with using public Internet access providers where it is not required, reducing the cost for both carriers.

Conclusion

While Ethernet has been the standard for data connectivity in the LAN for many years, only recently has it become a viable technology in the MAN and WAN. The ST-series enables carriers to offer Ethernet Private Line service with the same or better customer experience as that found in current ATM and Frame Relay services.