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DW Spectrum IPVMS Maximum System Size

DW Spectrum® IPVMS Maximum System Size


Affected Roles:  Administrator, Owner

Related Digital Watchdog VMS Apps:  DW Spectrum® IPVMS

Software Version:  DW Spectrum® IPVMS v4.2

Last Edit:  July 1, 2021


System Limitations

While DW Spectrum® IPVMS is scalable from one to thousands of devices, there are still limitations to be considered.  In addition to the hardware requirements of a DW Spectrum® Server, the restrictions that would otherwise impede the effectiveness of a DW Spectrum® System should be followed at all times.  Surpassing the recommended limitations when building a DW Spectrum® System can cause operating issues, video issues, network issues, etc.

This article will outline some of the operating limitations of DW Spectrum® IPVMS when considering deploying a large-scale DW Spectrum® System or in general.

Related Articles

Supported/Affected Devices:

  • DW Blackjack® Server Series

Terminology Glossary

The following terminology is commonly used when referring to DW Spectrum® IPVMS:

  • System – can be comprised of a single DW Spectrum® Server or of multiple DW Spectrum® Servers that have been merged into a single DW Spectrum® System
  • Server – refers to the computer where the DW Spectrum® Server software is installed.  The purpose of such servers is to receive video streams from cameras, manage local cameras, process and analyze video for analytics or other special settings.  Additionally, a DW Spectrum® Server is responsible for archiving and storing video footage, while also activing as the central device in the surveillance network.
  • Client – refers to the DW Spectrum® Client software portion of the IPVMS platform.  This application can be used as a GUI when managing and using the DW Spectrum® IPVMS program.  It is typically permissible to install both the DW Spectrum® Client software alongside the DW Spectrum® Server software for quick setting adjustments, however it is recommended to avoid using the DW Spectrum® Client application on the same computer for extended periods of time to avoid unnecessary processing consumption.  A good alternative would be to install the Client on a separate computer, then connect with the Server through the network.
  • Resource – when referring to a DW Spectrum® System, a “resource” is typically a reference to any device (IP camera, I/O device, standalone recorder, etc.) that has been registered and connected with a DW Spectrum® Server.

Single DW Spectrum® System Limits

The following limitations apply to DW Spectrum® Systems (overall) and are based on lab testing results, which may vary depending on the System’s environment (physical, network, etc.):

Maximum Recommended Elements for a Single System

Max. Recommended Servers


Max. Recommended Resources


Max. Recommended Users


Max. MEGApix CaaS (CaaS system only)


Max. DW Blackjack MINIs (same LAN)


Max. Network Throughput

1,000 Mbps

Camera and Video Stream Limit

Currently, there is a limit of 128 video streams per each DW Spectrum® Server and a limit of 10,000 resources overall per each DW Spectrum® System.  Surpassing the recommended limitations for a DW Spectrum® System can cause critical errors within the IPVMS platform.

However, DW Spectrum® IPVMS is a scalable platform. If there are more than 128 video streams planned for a DW Spectrum® System, additional DW Spectrum® Server can be added to the system to increase the number of video streams that can be safely used by the system.  For example, a system with two DW Blackjack® E-Rack servers in a merged DW Spectrum® System can safely support up to 256 video streams (128 streams x 2 servers = 256 streams).

**NOTE:  DW Blackjack® Servers can vary in the number of IP cameras that are supported, depending on the hardware model.  For example, a DW Blackjack® E-Rack supports up to 128 IP cameras, but a DW Blackjack® Cube only supports up to 64 IP cameras.  Please consider this when planning a DW Spectrum® System.

Video Thread Limit

When processing the media stream from an IP camera, the DW Spectrum® Server will create up to four (4) threads:

  • Thread 1 – reads a high-quality RTSP stream from the camera
  • Thread 2 – reads a low-quality RTSP stream from the camera
  • Thread 3 – processes the high-quality RTSP stream and uses a multiplexer to convert the input into .mkv format
  • Thread 4 – processes the low-quality RTSP stream and uses a multiplexer to convert the input into .mkv format

As a result, 128 cameras can require up to 512 threads in total.  While there is not a set limit of 512 threads in modern Operating Systems, our developers tested and concluded that when 512 threads is surpassed, there is a significant degradation in the DW Spectrum® System performance.

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  • 28-Jul-2021