Reliability and Resiliency

Service Delivery Switches are designed to deliver carrier-class reliability and availability that both metro and enterprise operators expect and demand for today’s business-critical network services environment. Service Delivery Switch resiliency and reliability are based on three major features:

• Modularized LE-OS software architecture with a real-time kernel
• Industry leading resiliency with Rapid Spanning Tree Protocol (IEEE 802.1w) that can be configured to support sub-50 millisecond failover time*
• Industry-standard IEEE 802.3ad Link Aggregation

* RSTP performance will vary by size and configuration of the network. Sub-50 millisecond failover time based on a test configuration with a 7-node ring and 8,000 MAC addresses. For more information on this test, see World Wide Packets White paper entitled “Network Resiliency.”

LE-OS is architected with a real-time kernel that delivers reliability and high availability by protecting against complete operating system failures.

Service Delivery Switches also deliver industry leading resiliency with an advanced optimization of the Rapid Spanning Tree Protocol (IEEE 802.1w). The LE-OS operating system common to all Service Delivery Switches can be configured to deliver less than 50 Millisecond failover times to support time-sensitive applications such as video and voice. The rapid failover capability delivered in all Service Delivery Switches enable deployment of time-sensitive applications with the same service level guarantees as SONET/SDH optical rings while being fully compatible with IEEE 802.1D Spanning Tree and IEEE 802.1w Rapid Tree Spanning Tree Protocols.

Service Delivery Switches also support IEEE 802.3ad Link Aggregation. 802.3ad supports bundling of several physical ports together to form one logical port. Service Delivery Switch Link Aggregation is a standard implementation of 802.3ad and delivers both interoperability and resiliency of the connection even if connectivity with one physical port is interrupted. Service Delivery Switch Link Aggregation support includes the Protection Link Aggregation feature that delivers a “hot standby” failover mechanism which provides a near wire-speed protection mechanism for the protected link aggregation group. When the failed link is restored, reversion to the initial configuration is programmable. Service Delivery Switches support ingress policing across a link aggregation enabling more efficient utilization and sharing of bandwidth among ports

Figure — RSTP Ring with Sub 50 msec Resiliency

• Sub 50 msec failover & restore
• QoS aware for maximum protection
• All services, including Unicast and Multicast Flows, are protected

Continue

• Introduction
• Configuration Flexibility
• Fast Service Roll-Out
• Low Cost Per Subscriber
• Common LE-OS Operating System
• Carrier Class QoS
• Reliabilty and Resiliency
• Advanced Security
• Carrier Class OAM

PDS-0009-001 Rev A.1