In Webex Meetings version 42.7 and later, the desktop app uses the following dedicated source port ranges to originate media traffic:

  • Audio and content audio port range: 52,000 to 52,049
  • Main and content video port range: 52,100 to 52,199

This allows you to mark media packets for QoS using the source port ranges and properly prioritize network traffic.

If you use the Webex Meetings desktop app on Windows, you must follow the guidance in this article to manually enable it for your organization. This includes enabling the desktop app to use the new source port ranges, configuring your firewall, and setting recommended DSCP values for media traffic using a group policy template.

  • You must have Windows administrative privileges to perform the tasks described below.
  • This article also applies to any organizations that use Webex App (Full-Featured meetings).
Enable the feature

Enable dedicated media source ports while installing the Webex Meetings desktop app using a command line parameter. The parameter adds the required Windows registry settings and the Windows Defender firewall access-control lists (ACLs).

You need the command line parameter during the initial installation only; Webex Meetings retains the configuration after all automatic upgrades.

If you use Webex App (Full-Featured meetings), you must ensure Webex App is installed before you perform this procedure.

1

Go to https://www.webex.com/downloads.html, scroll down to Other download options and then from the drop-down list beside Our previous app, Meetings, select Windows.

2

Add the following command line parameter for the MSI install:

msiexec /i webexapp.msi LOCALPORTRANGE="1"
If you download an MSI package with another name, then you must ensure you update the command line parameter.

Enable dedicated media source ports after installing the Webex Meetings desktop app using a batch file that you run on the Windows machine. The batch file adds the required Windows registry settings and the Windows Defender firewall access-control lists (ACLs).

Use this procedure to enable dedicated media source ports after an automatic upgrade to Webex Meetings desktop app 42.7 or later.

1

Open a text editor and paste the following code block into the file:

echo set registry to enable feature
reg add "HKLM\SOFTWARE\WOW6432Node\Webex\Policies" /v "LocalPortRange" /t REG_SZ /d "1" /f
reg add "HKLM\SOFTWARE\Webex\Policies" /v "LocalPortRange" /t REG_SZ /d "1" /f

echo set firewall inbound policy named "Cisco Webex Meetings" to avoid pop-up
netsh advfirewall firewall add rule name="Cisco Webex Meetings" dir=in program="%ProgramFiles(x86)%\Webex\Webex\Meetings\atmgr.exe" action=allow
netsh advfirewall firewall add rule name="Cisco Webex Meetings" dir=in program="%ProgramFiles%\Webex\Webex\Meetings\atmgr.exe" action=allow
netsh advfirewall firewall add rule name="Cisco Webex Meetings" dir=in program="C:\Users\%USERNAME%\AppData\Local\WebEx\WebEx\Meetings_slow\atmgr.exe" action=allow
netsh advfirewall firewall add rule name="Cisco Webex Meetings" dir=in program="C:\Users\%USERNAME%\AppData\Local\WebEx\WebEx\Meetings\atmgr.exe" action=allow
netsh advfirewall firewall add rule name="Cisco Webex Meetings" dir=in program="C:\Users\%USERNAME%\AppData\Local\WebEx\WebEx64\Meetings_slow\atmgr.exe" action=allow
netsh advfirewall firewall add rule name="Cisco Webex Meetings" dir=in program="C:\Users\%USERNAME%\AppData\Local\WebEx\WebEx64\Meetings\atmgr.exe" action=allow

If the Webex Meetings desktop app wasn’t initially installed using the default path, then you must update the EnablePortRange.bat file with the correct paths to set up the firewall policies.
2

Save the file as EnablePortRange.bat.

3

Run EnablePortRange.bat on the Windows machine to enable the dedicated media source ports.

Configure DSCP values using a group policy template
Use a group policy template to set DSCP values in your Windows group policy object (GPO). This ensures the Webex Meetings desktop app for Windows marks DSCP QoS using the dedicated source ports you enabled in the previous step.

The policy sets DSCP 46 for the audio port range (52,000 – 52,049) and DSCP 34 for the video port range (52,100 – 52,199). These are the recommended values, but can be modified if necessary.

1

Open a text editor and paste the following code block into the file:

CLASS MACHINE

CATEGORY !!WebEx:Cat_WebEx

CATEGORY !!CiscoWebex

POLICY !!WebExMeetingsAudioDSCP_Policy

   KEYNAME "Software\Policies\Microsoft\Windows\QoS\WebexAudioDSCP"

  #if version >= 4

    SUPPORTED !!SUPPORTED_WIN7

  #endif

  EXPLAIN !!WebExMeetingsDSCP_Explain

PART !!WebExMeetingsAudioDSCP_Part EDITTEXT

  VALUENAME "DSCP Value"

  MAXLEN 1000

      DEFAULT "46"

END PART

PART !!WebExMeetingsAudioPortRange_Part EDITTEXT

    VALUENAME "Local Port"

            MAXLEN 1000

    DEFAULT "52000:52049"

END PART

      ACTIONLISTON

            VALUENAME "Application Name" VALUE !!WebExMeetingsAppName_Part

            VALUENAME "Local IP" VALUE "*"

            VALUENAME "Local IP Prefix Length" VALUE "*"

            VALUENAME "Protocol" VALUE "*" VALUENAME "Remote IP" VALUE "*"

            VALUENAME "Remote IP Prefix Length" VALUE "*"

            VALUENAME "Remote Port" VALUE "*"

            VALUENAME "Throttle Rate" VALUE "-1"

            VALUENAME "Version" VALUE "1.0"

    END ACTIONLISTON

END POLICY

POLICY !!WebExMeetingsVideoDSCP_Policy

        KEYNAME "Software\Policies\Microsoft\Windows\QoS\WebexVideoDSCP"

    #if version >= 4

      SUPPORTED !!SUPPORTED_WIN7

    #endif

    EXPLAIN !!WebExMeetingsDSCP_Explain

    PART !!WebExMeetingsVideoDSCP_Part EDITTEXT

        VALUENAME "DSCP Value"

        MAXLEN 1000

            DEFAULT "34"

    END PART

    PART !!WebExMeetingsVideoPortRange_Part EDITTEXT

        VALUENAME "Local Port"

            MAXLEN 1000

    DEFAULT "52100:52199"

    END PART

        ACTIONLISTON

            VALUENAME "Application Name" VALUE !!WebExMeetingsAppName_Part

            VALUENAME "Local IP" VALUE "*"

            VALUENAME "Local IP Prefix Length" VALUE "*"

            VALUENAME "Protocol" VALUE "*"

            VALUENAME "Remote IP" VALUE "*"

            VALUENAME "Remote IP Prefix Length" VALUE "*"

            VALUENAME "Remote Port" VALUE "*"

            VALUENAME "Throttle Rate" VALUE "-1"

            VALUENAME "Version" VALUE "1.0"

  END ACTIONLISTON

END POLICY

END CATEGORY

END CATEGORY

[Strings]

WebEx:Cat_WebEx="Cisco WebEx Meetings"

CiscoWebex="Cisco WebEx Meetings General Settings"

SUPPORTED_WIN7="Microsoft Windows 7 or later"

WebExMeetingsDSCP_Explain="Configure DSCP value for Cisco Webex.\n\nIf this value configured, WebEx App will use these DSCP value for audio/video/sharing data if these data from dedicate local port range.\n\nAudio port range should be 52000:52049.\n\nVideo port range should be 52100:52199."

WebExMeetingsAppName_Part="atmgr.exe"

WebExMeetingsAudioDSCP_Policy="Configure Audio DSCP for Cisco Webex"

WebExMeetingsAudioDSCP_Part="Audio DSCP Configuration in Cisco Webex"

WebExMeetingsAudioPortRange_Part="Audio data port range"

WebExMeetingsVideoDSCP_Policy="Configure Video DSCP for Cisco Webex"

WebExMeetingsVideoDSCP_Part="Video DSCP Configuration in Cisco Webex"

WebExMeetingsVideoPortRange_Part="Video data port range"

2

Save the file as WebexDSCPPolicy.adm.

3

On your Windows machine, open the Group Policy Editor.

4

Go to Local Computer Policy > Computer Configuration, then right-click on Administrative Templates and select Add/Remove Templates.

5

Click Add, navigate to the WebexDSCPPolicy.adm file and then click Open.

6

Click Close.

A new Cisco Webex Meetings template appears under Classic Administrative Templates.
7

Expand Classic Administrative Templates > Cisco Webex Meetings and then click Cisco Webex Meetings General Settings.

8

Double-click Configure Audio DSCP for Cisco Webex.

9

Select Enabled and then click OK.

This sets DSCP 46 for the audio port range.

10

Double-click Configure Video DSCP for Cisco Webex.

11

Select Enabled and then click OK.

This sets DSCP 34 for the video port range.

The DSCP configuration is now complete. Alternatively, set DSCP in the network using the dedicated local source port ranges to match the traffic port identifiers and map the appropriate DSCP values. For more information about this, see  Cisco Preferred Architecture for Bandwidth Management for Webex.
Disable the feature

Use a batch file to disable the feature on the Windows machine.

1

Open a text editor and paste the following code block into the file:

echo set registry to disable feature
reg delete "HKLM\SOFTWARE\WOW6432Node\Webex\Policies" /v "LocalPortRange" /f
echo delete firewall policy
netsh advfirewall firewall delete rule name="Cisco Webex Meetings"
2

Save the file as DisablePortRange.bat.

3

Run DisablePortRange.bat on the Windows machine to disable the dedicated media source port feature.

The following actions also disable the feature:
  • Uninstalling the Webex Meetings desktop app.
  • Re-running the MSI without the LOCALPORTRANGE="1" parameter.