Multi Protocol Label Switching (MPLS) is a packet-switching technology that allows sharing of physical links in the service provider network among multiple customers. In these environments, each switching device within the network cloud represents a congestion point where IP packets will be dropped or re-ordered as a result of traffic bursts and oversubscription, creating contention for network resources. This is particularly true at the edge of the service provider network, where LAN traffic is stepped down to smaller WAN bandwidth rates.
Network congestion typically leads to packets being dropped. While packet loss rates vary widely, it is common to see 0.05% to 0.1% packet loss in normal traffic hours across service provider networks, with peaks reaching 2%. With congestion comes jitter and latency, which has a major impact on real time applications, like VoIP and streaming media. Applications that leverage TCP are also affected by congestion, because TCP has a built-in backoff mechanism that throttles back network traffic during periods of congestion. The result is degradation in performance for many applications.
Silver Peak Solution
The following relevant Silver Peak features mitigate impairments that arise specifically in shared packet-switching networks. These techniques enable enterprises to reap the cost benefits of MPLS without suffering from poor WAN quality:
Network Memory is used in conjunction with advanced compression techniques to reduce the amount of data traversing the WAN. This increase WAN efficiency, which helps to avoid congestion when possible.
Network Integrity protects traffic from collateral congestion in a shared service provider network by mitigating the impact of dropped and out-of-order packets. The Silver Peak solution adapts its Network Integrity techniques to accommodate changing WAN conditions, ensuring an optimal blend between Network Integrity overhead and application performance.
QoS is used to prioritizes traffic types, and allocate bandwidth accordingly. This improves jitter and latency by enforcing specific policies that govern how to route downstream traffic.Silver Peak can both honor and set DSCP/MPLS markings on a per-application basis for added QoS granularity.
Network Acceleration overcomes WAN latency by addressing TCP chattiness. This is achieved using standard TCP acceleration techniques, such as adjustable windows and selective acknowledgements.
With Silver Peak, enterprises get the best of all MPLS worlds - cost effective bandwidth and ease of provisioning, with performance that equals private line and cell-based technologies.
