Omnissa Horizon Blast Extreme

The Horizon Blast Extreme display protocol was developed by Omnissa for use in Horizon deployments to provide remote access to desktops and published applications.

Horizon Blast Extreme is designed to work well with a wide variety of devices and network topologies and to adapt gracefully to changing network latency and bandwidth, and can use both TCP and UDP network transports.

Supported use cases

The Horizon Blast Extreme display protocol can be used for remoting:

• Windows and Linux desktops running on virtual machines
• Shared-session desktops on a Windows Remote Desktop Services (RDS) host or a Linux host
• Published applications on a Windows Remote Desktop Services (RDS) host or a Linux host
• Linux desktops running on physical machines
• Windows desktops running on physical machines (this use case requires Enterprise Edition of Windows 10 RS4 or later builds)

The Windows RDS host can be a physical machine or a virtual machine.

Video codecs and Horizon Blast Extreme

Internally, Horizon Blast Extreme uses a variety of video codecs for remoting screen contents, including the industry-standard H.264, HEVC, and AV1 codecs, and Omnissa's own BlastCodec.

Horizon Blast Extreme makes use of GPU hardware acceleration for the aforementioned industry-standard codecs when available. Hardware decoding is especially useful for mobile devices because it significantly reduces CPU consumption and extends battery life. Hardware encoding brings improved performance for multimedia workloads, enabling high frame rates and lower latency when using high resolution and multiple monitor topologies.

The software-based BlastCodec provides a high-quality desktop remoting experience using software encoding. BlastCodec natively provides High Definition Color, and uses less bandwidth than the hardware encoders for a similar level of display quality.

Horizon Blast Extreme detects the presence of a vGPU system and applies higher quality default settings. There is a unified image quality configuration setting that controls the remote display image quality level across all encoders supported by Horizon Blast Extreme. For more information about Omnissa Horizon Blast Extreme policy settings, see the Horizon Remote Desktop Features and GPOs guide in the Omnissa Horizon documentation.

The BlastCodec encoder

BlastCodec is Horizon's current default software encoder.

BlastCodec provides sharper text and images as well as reduced bandwidth usage than the previous default software encoders that Horizon Blast Extreme supported (H.264 and Adaptive encoders).

BlastCodec operates like a video codec with motion detection, motion vectors, and inter-predicted macroblocks. BlastCodec also efficiently encodes screen content typical for software and office applications.

BlastCodec is currently supported on all Horizon Clients except on mobile devices. Mobile devices use the H.264 hardware decoder.

Horizon Blast Extreme Features

This section lists some of the many features that Horizon Blast Extreme supports. For in-depth details, see the Omnissa Tech Zone documents Omnissa Horizon Blast Extreme Display Protocol and Omnissa Blast Extreme Optimization Guide.

Network-related

• Users outside the corporate firewall can use this protocol with the corporate virtual private network (VPN), or users can make secure, encrypted connections to the Omnissa Unified Access Gateway appliance in the corporate DMZ. Note: It is not recommended to use VPN since Horizon Blast Extreme connections are already encrypted. For a better user experience, use the Unified Access Gateway appliance instead.
• Advanced Encryption Standard (AES) 128-bit encryption is supported and is turned on by default. You can, however, change the encryption key cipher to AES-256.
• Connections from all types of client devices are supported.
• The Horizon Windows Client, Horizon Linux Client, and Horizon Mac Client recover automatically from momentary network loss of up to two minutes.

Visual and audio related features

• 32-bit color is supported for virtual displays.

• ClearType fonts are supported.

• Audio redirection with dynamic audio quality adjustment for LAN and WAN.

• Real-Time Audio-Video for using webcams and microphones on some client types.

• Copy and paste of text and, on some clients, images between the client operating system and a remote desktop or published application. For other client types, only copy and paste of plain text is supported. You cannot copy and paste system objects such as folders and files between systems.

• Horizon Blast Extreme implements High Dynamic Range (HDR) encoding, which expands the range of brightness in a digital image to provide a more realistic depiction of a scene. HDR is enabled by default on the agent. You can add these optional registry keys REG_SZ (string value) on a Windows agent:

  • PixelProviderHDRReferenceWhite: an integer greater than 0 that controls the relative brightness of the paper white level. The default value is 80.

  • TopologyHDREnabled = 1 to enable HDR. The default value is 1.

  • TopologyHDREnabled = 0 to disable HDR.

  On the client:

  • For Horizon 2412 and later: set the optional registry key REG_SZ (string value) HKEY_LOCAL_MACHINE\SOFTWARE\Omnissa\Horizon\Client\AllowClientHDR to True or False for HDR topology requests. The default value is True.

  • For Horizon versions earlier than 2412, please contact Omnissa Support for the precise registry key name in your Horizon version.

  • In the client's settings (Settings > Horizon Blast) turn on Allow High Efficiency Video Decoding (HEVC) and Allow High Dynamic Range Decoding (HDR).

Bandwidth-related

• Settings for Horizon Blast Extreme can be controlled by administrators to tune the display protocol to favor reduced bandwidth usage or higher display quality.

• You can specify the bandwidth bursting interval for data sent to clients to minimize bandwidth spikes using the registry key MaxBandwidthBurstMsec. The regkey config is a REG_SZ (string value) even though it contains a number. The default is 1000.

  MaxBandwidthBurstMsec configures the interval of time, in milliseconds, during which the network bandwidth can temporarily exceed the bandwidth cap set by MaxBandwidthKbps. For example, if MaxBandwidthKbps = 1000, then during a one-second interval, the output must not exceed 4 Kbits. However, these 4 Kbits of data can be output as a concentrated burst at the start of the one-second interval or can be distributed throughout the one-second interval, as needed.

  For Horizon version 2412 or later: On a Horizon Windows Agent, you would enable the Max Session Bandwidth policy setting and then set the registry key HKLM\SOFTWARE\Omnissa\Horizon\Blast\Config\MaxBandwidthBurstMsec

  For Horizon versions earlier than 2412, please contact Omnissa Support for the registry key to set.

• By default, the Horizon Blast Extreme session has a maximum bandwidth cap that is proportional to the number of pixels on the remoted screens. You can determine the maximum bandwidth cap, in kilobits per second (Kbps), for the session, based on the total screen area available for the session. This maximum bandwidth cap is calculated from the equation

  MaxBandwidthCap = Offset + (Slope * ScreenArea)
  

  where

  • Offset is the value, in Kbps, defined by MaxBandwidthKbpsPerMegaPixelOffset. The default is 0.
  • Slope is the value, in Kbps per megapixel, defined by MaxBandwidthKbpsPerMegaPixelSlope (or by the corresponding Max Session Bandwidth kbit/s Megapixel Slope GPO). The minimum value is 100. The maximum value is 100000. The default is 6200.
  • ScreenArea is the total available screen area, in megapixels, of the monitors used to display the Horizon Blast Extreme session. This megapixel screen area is detected automatically during the session.

  Note: The maximum bandwidth actually allowed is the lesser of the following values:

  • The maximum bandwidth configured in the Max Session Bandwidth policy or explicitly via the MaxBandwidthKbps registry key.
  • The maximum bandwidth cap calculated from MaxBandwidthKbpsPerMegaPixelOffset and MaxBandwidthKbpsPerMegaPixelSlope (or by the corresponding Max Session Bandwidth kbit/s Megapixel Slope GPO).

  Configurations specified in Group Policies take precedence over configurations made in the corresponding regkey.

External-device related

• USB redirection is supported for some client types.

• Multimedia redirection is supported for some Windows client operating systems and some remote desktop operating systems (with Horizon Agent installed).

• Multiple monitors are supported for some client types. On some clients, you can use up to four monitors with a resolution of up to 2560 x 1600 per display or up to three monitors with a resolution of 4K (3840 x 2160) for Windows desktops, depending on your hardware version. Pivot display and autofit are also supported.

  When the 3D feature is enabled, up to two monitors are supported with a resolution of up to 1920 x 1200, or one monitor with a resolution of 4K (3840 x 2160).

• Connections to physical machines that have no monitors attached are supported with NVIDIA graphics cards. For best performance, use a graphics card that supports H.264 encoding.

  If you have an add-in discrete GPU and an embedded GPU, the operating system might default to the embedded GPU. To fix this problem, you can disable or remove the device in Device Manager. If the problem persists, you can install the WDDM graphics driver for the embedded GPU, or disable the embedded GPU in the system BIOS. Refer to your system documentation on how disable the embedded GPU.

  CAUTION: Disabling the embedded GPU might cause future loss of access to functionality such as console access to BIOS setup or NT Boot Loader.

Client device support for specific Horizon Blast Extreme features

For information about which client devices support specific Horizon Blast Extreme features, see the Omnissa Horizon Client documentation.

Performance counters with Horizon Agent on Windows

Horizon Agent on Windows provides performance counters which can be displayed using the PerfMon tool on Windows. These counters provide an accurate representation of the current state of the system, in real time, for the following internal subsystems:

• Horizon Blast Extreme session
• Imaging
• Audio
• CDR
• USB - Note: The USB counters displayed using PerfMon on Windows are valid if USB traffic is configured to use Horizon Virtual Channel (also known as VVC).
• Skype for Business: counters are for control traffic only.
• Clipboard
• RTAV
• Serial port and scanner redirection features
• Virtual printing
• HTML5 multimedia redirection (MMR)
• Note: For Windows multimedia redirection, performance counters appear only if you configured this feature to use Horizon Virtual Channel (also known as VVC).

Wake-on-LAN

In Horizon environments, Wake-on-LAN is supported for physical machines with the Enterprise edition of Windows 10 RS4 and later. With this feature, users can wake up physical machines when connecting with the Horizon Connection Server.

The Wake-on-LAN feature has these prerequisites:

• Wake-on-LAN (WoL) is only supported on IPv4 environments.

• The physical machine must be configured to wake up on receiving Wake-on-LAN packets when Wake-on-LAN is enabled in the BIOS settings as well as network card settings.

• Destination port 9 is used for WoL packets from the Horizon Connection Server.

• WoL packets are IP-directed broadcast packets that must be able to reach Horizon Agent when sent from the Horizon Connection Server. Wake-on-LAN functions in these scenarios:

  • The Horizon Connection Server and the Horizon Agent on the physical machine are on the same subnet in a LAN environment.
  • All routers between the Horizon Connection Server and Horizon Agent are configured to allow the IP-directed broadcast packet for the target subnet of the physical machine you want to wake up.

Note: The Wake-on-LAN feature does not support floating-assignment pools of a physical Windows 10 agent. The WoL packet is only sent to dedicated assignment pools entitled with a particular user.

Recommended Guest Operating System Settings

1 GB of RAM or more and a dual CPU is recommended for playing in high-definition, full screen mode, or 720p or higher formatted video. To use Virtual Dedicated Graphics Acceleration for graphics-intensive applications such as CAD applications, 4 GB of RAM is required.

Video Quality Requirements

480p-formatted video

You can play video at 480p or lower at native resolutions when the remote desktop has a single virtual CPU. If you want to play the video in high-definition mode or in full screen mode, the desktop requires a dual virtual CPU. Even with a dual virtual CPU desktop, as low as 360p-formatted video played in full screen mode can lag behind audio, particularly with Horizon on Windows clients.

720p-formatted video

You can play video at 720p at native resolutions if the remote desktop has a dual virtual CPU. Performance might be affected if you play videos at 720p in high definition or in full screen mode.

1080p-formatted video

If the remote desktop has a dual virtual CPU, you can play 1080p formatted video, although the media player might need to be adjusted to a smaller window size.

3D rendering

You can configure remote desktops to use software- or hardware-accelerated graphics. The software-accelerated graphics feature enables you to run DirectX 9 and OpenGL 2.1 applications without requiring a physical graphics processing unit (GPU). The hardware-accelerated graphics features enable virtual machines to either share the physical GPUs (graphical processing unit) on a vSphere or Nutanix AHV host or dedicate a physical GPU to a single virtual desktop.

For 3D applications, up to two monitors are supported, and the maximum screen resolution is 1920 x 1200.

For more information about 3D features, see Using 3D Graphics Applications.

Hardware Requirements for Client Systems

For information about processor and memory requirements for the specific type of desktop or mobile client device, see the Horizon Client documentation.