Managing and restricting call bandwidth

You can restrict the amount of bandwidth used by each participant when dialed in to a Pexip Infinity service (Virtual Meeting Room, Virtual Auditorium, Virtual Reception, scheduled conference, Media Playback Service, or Test Call Service), or for Infinity Gateway calls or other outbound calls that are managed by Call Routing Rules. You can place restrictions on the bandwidth received by participants, sent by participants, or both.

Bandwidth restrictions can be configured on a global basis, or on each individual service or routing rule. Settings applied to an individual service override any global limits that have been applied.

When sending main video and presentation to a standards-based endpoint, you can also control the maximum percentage of the call bandwidth to allocate to the presentation content (see presentation bandwidth requirements).

If a Virtual Reception has bandwidth limits, these only apply to participants while they are in the Virtual Reception. When the call is transferred to the selected Virtual Meeting Room or Virtual Auditorium, any bandwidth restrictions for that service will then apply.

When dialing out from a conference, the outbound call bandwidth limit is inherited from the VMR's bandwidth settings. (If a Call Routing Rule is applied, the rule's bandwidth settings are not used.)

Inbound bandwidth restrictions are implemented as requests to the participant endpoints to limit their bandwidth to the specified amount. It is important to note that endpoints ultimately decide what bandwidth and resolution they send — Pexip Infinity cannot actually enforce inbound restrictions. However, Pexip Infinity is responsible for deciding what gets sent to the endpoints.

Restricting video call resolutions

If you want to limit video calls to specific resolutions (and limit the transcoding node resources that are reserved for calls), you should use the Maximum call quality setting (see Setting and limiting call quality for more information).

However, bandwidth settings also affect the call resolution as shown below. If there is insufficient bandwidth (the Maximum bandwidth settings configured against the service) to support the Maximum call quality then the participant's call will use a lower resolution as appropriate for the available bandwidth (and consume less transcoding node resource).

Minimum call bandwidth requirements

This table shows the minimum bandwidth required for Pexip Infinity to be able to send different video resolutions. Note that this does not include the audio component, which can add between 8 kbps and 64 kbps.

Video resolution Minimum required bandwidth
Full HD (1080p)

2400 kbps

(1600 kbps for VP9)

HD (720p)

960 kbps

(640 kbps for VP9)

SD (448p) 448 kbps
SD (QCIF) 64 kbps

Note that when compared to standards-based endpoints, the WebRTC VP9 codec provides the same resolution at a lower bandwidth, but consumes around 25% more resource on the Conferencing Node. This is why you should use Maximum call quality rather than bandwidth restrictions to limit resource consumption.

In most cases you should apply the same bandwidth restrictions to the inbound and outbound calls within a service. However, for example, if you want to allow participants to send their video as SD, but receive the composed layout of all participants (main video and video thumbnails) as HD, you would set the inbound call bandwidth to 960 kbps and the outbound to 1800 kbps (although these settings would not limit clients using VP9).

Applying bandwidth restrictions to an entire deployment

To restrict the bandwidth of calls across your entire deployment:

  1. Go to Platform > Global settings.
  2. In the Service configuration section, enter the desired values in the following fields:

    Option Description
    Maximum inbound call bandwidth (kbps)

    Limits the bitrate of media received by Pexip Infinity from a participant.

    Leave blank if you do not want to apply any restrictions.

    This can be overridden by any services or rules that have a specific Maximum inbound call bandwidth configured.

    Maximum outbound call bandwidth (kbps)

    Limits the bitrate of media sent from Pexip Infinity to a participant.

    Leave blank if you do not want to apply any restrictions.

    This can be overridden by any services or rules that have a specific Maximum outbound call bandwidth configured.

Applying bandwidth restrictions to a service or Call Routing Rule

To restrict the bandwidth of calls to a particular service or Call Routing Rule:

  1. Go to the relevant service or rule:

    • Services > Virtual Meeting Rooms
    • Services > Virtual Auditoriums
    • Services > Virtual Receptions
    • Services > Scheduled conferences
    • Services > Call routing
  2. Either select the name of the service or rule you wish to edit, or click Add.
  3. In the Advanced options section, select Show (not required for Call Routing Rules).
  4. Enter the desired values in the following fields:

    Option Description
    Maximum inbound call bandwidth (kbps)

    Limits the bitrate of media received by Pexip Infinity from a participant.

    Leave blank if you do not want to apply any restrictions.

    This overrides any global Maximum inbound call bandwidth that may have been configured.

    Maximum outbound call bandwidth (kbps)

    Limits the bitrate of media sent from Pexip Infinity to a participant.

    Leave blank if you do not want to apply any restrictions.

    This overrides any global Maximum outbound call bandwidth that may have been configured.

  5. Select Save.

Presentation bandwidth requirements

Bandwidth usage for presentation streams depends on the type of client:

  • When sending main video and presentation content to a conference participant on a standards-based (SIP or H.323) endpoint, Pexip Infinity splits the available bandwidth between main video and content.

    • By default up to 75% of the available call bandwidth is allocated to presentation content (and thus 25% is allocated to main video). You can modify this ratio at the global platform level via Platform > Global Settings > Service configuration > Maximum presentation bandwidth ratio.
    • The resolution and frame rate used for presentation content adapts dynamically to match the presented content, and the Maximum call quality is used to determine the maximum frame rate that Pexip Infinity will send for a given resolution. For example, if the maximum call quality is HD, then the maximum frame rate for Full HD content is 13 fps, but if an incoming presentation is Full HD at 4 fps then Pexip Infinity will send 4 fps.
  • When using a WebRTC-based Infinity Connect client to present content or to receive full motion (HD) presentation, the bandwidth is not shared. The presentation stream is treated as a separate call and has the same bandwidth limit applied as the main video call.
  • When sending main video and presentation content to a Skype for Business / Lync client, the bandwidth is not shared (this applies to VbSS and RDP). The presentation stream is treated as a separate call and has the same bandwidth limit applied as the main video call.
  • When sending presentation content to Microsoft Teams, Pexip always sends content to Teams at Full HD (1080p) at a frame rate requested by Teams. The resolution and frame rate of content sent from Microsoft Teams is determined by Teams.
  • When sending main video and presentation content to a Google Meet meeting, the presentation stream is treated as a separate call and has the same bandwidth limit applied as the main video stream. When sending video or presentation content to Pexip Infinity, Google Meet does not have any fixed bandwidth limitations — it dynamically downspeeds and upspeeds individual calls in response to network conditions, although it typically will not exceed 2 Mbps.