QoS classification for Citrix traffic

RiOS 9.x does not support packet-order queueing or latency priorities with Citrix traffic. We recommend using either the Autonegotiation of Multi-Stream ICA feature or the Multi-Port feature to classify Citrix traffic types for QoS.

RiOS 8.6.x and earlier provide a way to classify Citrix traffic using QoS to differentiate between different traffic types within a Citrix session. QoS classification for Citrix traffic is beneficial in mixed-use environments where Citrix users perform printing and use drive-mapping features. Using QoS to classify Citrix traffic in a mixed-use environment provides optimal network performance for end users.

Citrix QoS classification provides support for Presentation Server 4.5, XenApp 5.0 and 6.0, and 10.x, 11.x, and 12.x clients.

• Latency priority—The Citrix traffic application priority affects traffic latency, which allows you to assign interactive traffic a higher priority than print or drive-mapping traffic. A typical application priority for interactive Citrix sessions, such as screen updates, is real-time or interactive. Keep in mind that priority is relative to other classes in your QoS configuration.

• Bandwidth allocation (also known as traffic shaping)—When configuring QoS for Citrix traffic, it is important to allocate the correct amount of bandwidth for each QoS traffic class. The amount you specify reserves a predetermined amount of bandwidth for each traffic class. Bandwidth allocation is important for ensuring that a given class of traffic cannot consume more bandwidth than it is allowed. It is also important to ensure that a given class of traffic has a minimum amount of bandwidth available for delivery of data through the network.

The default ports for the Citrix service are 1494 (native ICA traffic) and 2598 (session reliability). To use session reliability, you must enable Citrix optimization on the appliance in order to classify the traffic correctly. You can enable and modify Citrix optimization settings under Optimization > Protocols: Citrix.

You can use session reliability with optimized traffic only. Session reliability with RiOS QoS does not support pass-through traffic. For details about disabling session reliability, go to
http://support.citrix.com/proddocs/index.jsp?topic=/xenapp5fp-w2k8/ps-sessions-sess-rel.html.

If you upgrade from a previous RiOS version with an existing Citrix QoS configuration, the upgrade automatically combines the five preexisting Citrix rules into one.