Your connection should at least have 100 kbps of upload and download bandwidth per VoIP line. Most modern broadband plans offer more than 100 Mbps of bandwidth (100X more than what you need). Monitor your past usage and account for growth in headcount and data usage. Employees frequently stream their favorite music, watch YouTube videos, and manage customers using CRM software, so you have to support more data than phone calls. The data consumed by VoIP isn’t massive, but it is a factor you need to monitor closely due to network congestion, latency, and security.