Determine your WAN bandwidth needs for multi-site connectivity, factoring in VoIP, video conferencing, cloud applications, SD-WAN, and redundancy requirements.
| Application | Per User / Stream | Direction | Latency Sensitive | Notes |
|---|---|---|---|---|
| VoIP Call | 100 Kbps | Symmetric | Yes (<30ms) | Per concurrent call, G.711 codec |
| Video (SD) | 1.5 Mbps | Symmetric | Yes (<50ms) | Per active video stream |
| Video (HD) | 4 Mbps | Symmetric | Yes (<50ms) | Per active video stream, 1080p |
| Video (4K) | 15 Mbps | Symmetric | Yes (<50ms) | Boardroom / presentation quality |
| Cloud CRM/ERP | 0.5–2 Mbps | Download-heavy | No | Depends on data complexity |
| File Sharing | 1–5 Mbps | Both | No | Sync traffic can burst higher |
| Remote Desktop | 2–5 Mbps | Download-heavy | Yes (<30ms) | Per active session |
| General SaaS | 0.5–1 Mbps | Download-heavy | No | Office 365, Google Workspace |
Bandwidth requirements are per user or per stream at typical usage levels. Actual usage depends on specific applications and usage patterns. View our networking solutions
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Multi-site connectivity requirements typically start around 20-50 Mbps per site for basic cloud and email use, rising sharply with VoIP call volume, video conferencing, and SD-WAN overhead. Businesses running centralised applications between sites often need dedicated bandwidth headroom of 30% above measured peak usage.
A typical VoIP call uses 80-100 kbps per line depending on the codec, so a 20-user office running calls simultaneously should budget roughly 2 Mbps just for voice traffic, separate from data and video needs. Poor bandwidth allocation for VoIP is one of the most common causes of call quality complaints.
SD-WAN intelligently routes traffic across multiple connections (broadband, leased lines, 4G/5G) to prioritise critical applications and improve resilience between sites. It typically becomes worthwhile once you have three or more locations, or when uptime for cloud applications and VoIP is business-critical.
Add up concurrent users per site multiplied by typical per-application usage (Microsoft 365 apps average 1-2 Mbps per active user, video calls 1.5-3 Mbps each), then add 20-30% overhead for backups and unexpected peaks. This calculator applies that method using your site count and application mix.
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