Bandwidth Requirements

The bandwidth used by CoreNexa will be adjusted for the best experience based on the user’s network connection.

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1:1 Video Calling

Upstream & Downstream:

• 500 kbps (up/down) for High-quality video (default resolution)
• 1.2 Mbps (up/down) for HD (720p) video
• 2.5 Mbps (up/down) for Full HD (1080p) video

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Group Meetings & Webinars

Upstream

• Number of users × resolution bandwidth

  • 500 kbps up for High-quality video (default)
  • 1.2 Mbps (up/down) for HD (720p) video
  • 2.5 Mbps (up/down) for Full HD (1080p) video

Downstream

Depends on how many attendees and their resolutions—but never more than 3.5 Mbps per meeting.

• The two most recent talkers each get the bandwidth they send.
• Remaining bandwidth is shared evenly among all other participants.

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Bandwidth Requirements by Resolution

Video is the largest consumer of bandwidth in CoreNexa. Below is how to calculate per-meeting requirements.

CoreNexa Mode	Width	Height	Color Depth (bits)	fps	Frame Size (bits)	Frame Size (Mbit)	Frame Size (MByte)	Est. Bandwidth (Mbps)	Est. Bandwidth (MBps)	w/ Compression (Kbps)	w/ Compression (Mbps)	w/ Compression (MBps)
Low	172	96	32	30	528 384	0.504	0.063	15.12	1.89	150	0.15	0.02
Standard	352	192	32	30	2 162 688	2.063	0.258	61.88	7.73	300	0.29	0.04
High	640	360	32	30	7 372 800	7.031	0.879	210.94	26.37	400	0.39	0.05
HD (720p)	1280	720	32	30	29 491 200	28.125	3.516	843.75	105.47	700	0.68	0.09
Full HD	1920	1080	32	30	66 355 200	63.281	7.910	1 898.44	237.30	2 000	1.95	0.24

Notes:

• Kbps = Kilobits per second (1 Kb = 1 024 bits)
• Mbps = Megabits per second (1 Mb = 1 024 Kb = 1 048 576 bits)
• MBps = Megabytes per second (1 B = 8 bits; so MBps = Mbps ÷ 8)
• Frame Size = Width × Height × Color Depth
• Est. Bandwidth does not include transmission overhead

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Inbound Video from Participants

• Reflects each remote user’s upstream bandwidth.
• Default mode is High (640×360)—a good balance between quality and bandwidth.
• In the Desktop Client, users can cap their upstream bandwidth per camera.
• If resolution is raised to HD or Full HD without increasing “Allowed Upstream,” the frame rate will automatically drop to compensate.

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Outbound Video to Each Participant

• Managed by the RNode:

  • Always caps total outgoing video to 3 584 Kbps (3.5 Mbps) per meeting.
  • The current and previous talkers get full bandwidth; all others share the remainder.

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Calculation Examples

Assume one office with 10 users sending/viewing video at High resolution:

1. Upstream (to Internet): 10 users × 0.39 Mbps = 3.9 Mbps
2. Downstream (from Internet): 10 users × 3.5 Mbps = 35 Mbps

If all switch to Full HD:

• Upstream: 10 × 1.95 Mbps = 19.5 Mbps
• Downstream: remains 35 Mbps

These are estimates; actual throughput may vary with overhead.

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Miscellaneous

• Screen Sharing only (no video thumbnails): 100 kbps
• Audio VoIP: 60–80 kbps
• Phone audio: 60–100 kbps