Voice over IP transmits voice calls over the internet. It converts voice into data packets. It sends them over the network. It reassembles them at the other end. VoIP is cheaper than traditional telephony. It offers more features. It works anywhere there is internet.

VoIP uses protocols like SIP, H.323, and RTP. SIP sets up and tears down calls. RTP carries the audio. Codecs compress the voice. G.711, G.729, and Opus are common. Latency and jitter must be managed. Packet loss degrades quality. Quality of service helps prioritize voice traffic.

VoIP types

• Softphone: app on computer or phone
• Desk phone: hardware with VoIP
• ATA: adapter for analog phones
• IP PBX: business phone system
• Hosted: cloud-based service

VoIP replaced traditional telephony for many businesses. It is flexible and cheap. It integrates with email, video, and messaging. It is used by WhatsApp, Skype, and Zoom. The voice is just another data stream. The internet is the new phone network.