Silver Peak provides a variety of Quality of Service (QoS) solutions for enterprises. In addition to honoring existing QoS markings, the Silver Peak solution provides native support for advanced QoS, including sophisticated application classification logic with Deep Packet Inspection (DPI), a variety of packet marking techniques, queuing, and traffic shaping.
Application Classification
WAN acceleration solutions require robust application classification capabilities in order to apply QoS to individual types of traffic. Silver Peak employs a variety of techniques to achieve this, which include:
- Five-tuple Filters. Applications can be classified using the five basic elements of a flow: source IP, destination IP, source port, destination port, and protocol.
- Stateful Deep Packet Inspection. Many applications, like FTP and VoIP, initiate connections that do not use well known ports for data transfer. Stateful classification with DPI is required in order to track these more complex applications.
Packet Marking
Packet marking provides a way for network elements to provide different levels of service to different packets, based on markings in the IP header. Using packet marking avoids the need to reclassify packets by deep inspection at each hop, and avoids the need to maintain per hop state within the network. By marking packets, Silver Peak appliances can provide hints that enable downstream devices, such as WAN routers, to treat each packet appropriately. Silver Peak’s packet marking functionality can be used even when other QoS features, such as shaping, are disabled.
Silver Peak provides the following packet marking functions for maximum flexibility, particularly when enterprises are delivering applications over service provider networks:
- Mark WAN packets based on Application Classification
- Mark WAN packets according to incoming LAN packets
- Mark LAN packets based on Application Classification
- Leave LAN packet markings unchanged
Queuing and Shaping
The most likely congestion points in a typical enterprise are on the near and far sides of the WAN. Silver Peak employs various QoS mechanisms to improve traffic delivery through these congestion points, including queuing policies, dropping disciplines, and service disciplines. Traffic classes can be assigned an absolute priority, a minimum bandwidth guarantee, a maximum bandwidth limit, an excess bandwidth allocation weight, and maximum queues sizes. Real-time applications can be guaranteed by configuring a maximum wait time.
Silver Peak appliances are also equipped with a variety of tools to shape traffic across an enterprise network. These include interface traffic shaping, peer traffic shaping, and classes of service algorithms.
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