Product Documentation

Network traffic priorities

Jun 13, 2017

Priorities are assigned to network traffic across multiple connections for a session with quality of service (QoS)-supported routers. Four TCP streams (real-time, interactive, background, and bulk) and two UDP streams (for voice and for Framehawk display remoting) are available to carry ICA traffic between the user device and the server. Each virtual channel is associated with a specific priority and transported in the corresponding connection. You can set the channels independently, based on the TCP port number used for the connection.

Multiple channel streaming connections are supported for Virtual Delivery Agents (VDAs) installed on Windows 10, Windows 8 and Windows 7 machines. Work with your network administrator to ensure the Common Gateway Protocol (CGP) ports configured in the Multi-Port Policy setting are assigned correctly on the network routers.

Quality of service (QoS) is supported only when multiple session reliability ports, or the CGP ports, are configured. 

Caution: Use transport security when using this feature. Citrix recommends using Internet Protocol Security (IPsec) or Transport Layer Security (TLS). TLS connections are supported only when the connections traverse a NetScaler Gateway that supports multi-stream ICA. On an internal corporate network, multi-stream connections with TLS are not supported.
To set quality of service for multiple streaming connections, add the following Citrix policy settings to a policy (see Multi-stream connections policy settings for details):
  • Multi-Port policy - This setting specifies ports for ICA traffic across multiple connections, and establishes network priorities.
    • Select a priority from the CGP default port priority list; by default, the primary port (2598) has a High priority.
    • Enter additional CGP ports in CGP port1, CGP port2, and CGP port3 as needed, and identify priorities for each. Each port must have a unique priority.

    Explicitly configure the firewalls on VDAs to allow the additional TCP traffic.

  • Multi-Stream computer setting - This setting is disabled by default. If you use Citrix NetScaler SD-WAN with Multi-Stream support in your environment, you do not need to configure this setting. Configure this policy setting when using third-party routers or legacy Branch Repeaters to achieve the desired Quality of Service (QoS).
  • Multi-Stream user setting - This setting is disabled by default.

For policies containing these settings to take effect, users must log off and then log on to the network.