How Do VoIP Phones Work?
Learn the basics of VoIP technology and how it is used by our desk phones, cordless handsets, and softphone apps for communication.
Written by Val Campos
Updated at February 24th, 2025
Table of Contents
What is VoIP?
VoIP stands for Voice Over Internet Protocol. VoIP allows phone calls to be made over the internet without the use of analog lines. Instead of sending the data through copper telephone wires, VoIP services convert the sound from the phone into packets of data that are sent to another destination over the Internet.
As long as the local internet connection is stable and robust, the packets will be sent and received to allow users to have a live conversation over their desk phone.
Analog VS. VoIP: What is the Difference?
| Analog | VoIP |
|---|---|
|
• Copper wires, or other cabling mediums, are used to transmit calls through an on-site PBX system or a Plain Old Telephone Service (POTS) network that relies on circuit switching to direct calls. • Some analog service providers are decommissioning traditional copper wire telephone networks as copper-based systems are aging and degrading, making maintenance burdensome and unreliable. • Maintaining and installing copper lines can be expensive, time-consuming, and inaccessible for some businesses. time. • Adding more analog landlines requires an on-site installation of physical cabling, which can be inconvenient and interruptive for businesses. • Some analog lines rely on roll over numbers (also known as call waiting) to handle multiple incoming calls. • Analog users can be limited in how they can manage their analog phone system and its features. |
• A broadband internet connection is used to transmit call data through SIP messaging. • Can be more cost-effective since IP phones function off of a power connection and a Wi-Fi or ethernet connection. • VoIP rely on virtual extensions, or seats (Users), to be able to place and receive calls through virtual lines. • A virtual extension can have multiple devices registered to it, allowing for a single user to switch between devices as needed. • More virtual extensions, or seats, can be added and configured virtually without the need for a technician to do an on-site installation. • Adding lines to a phone does not require an on-site installation. • SpectrumVoIP users are able to use a web portal to manage their phone system as VoIP allows for more customization and advanced call routing options. |
What are IP Phones?
IP (Internet Protocol) phones are computing devices that look like phones. Instead of relying on a circuit-switched wired network from a provider, IP phones use VoIP (Voice over Internet Protocol) to send data wirelessly across the Internet. An IP device, such as a desk phone, computer, etc., require a power connection and a reliable internet connection to function.
What Factors Affect My Phone's Calls?
Since IP devices (e.g., SpectrumVoIP's desk phones, cordless handsets, and softphone apps using Wi-Fi) rely on an internet connection, any outages and issues present in the location's network will be experienced through the phones as well. These network issues include latency, packet loss, and jitter.
What is Latency?
Latency is the measurement of the time it takes for data packets to reach a destination. For VoIP, if latency is too high (usually above 150ms) then calls will experience audio issues due to the high delay in voice packets reaching their destination.
What is Packet Loss?
Packet Loss occurs when packets of information do not reach their end destination and get “lost”. In a VoIP call, this can be heard as choppy audio that makes the call appear “staticky”, “jumbled”, or “stuttery".
If there is a large, noticeable amount of packet loss, phone calls made through a VoIP system may experience more difficult symptoms, like one-way audio and connection issues.
NOTE: Even a 1% packet loss can significantly degrade phone call quality.
What is Jitter?
The variation in the delay of received packets is called jitter.
On the sending side, packets are sent in a continuous stream with the packets spaced evenly apart. Due to internet network congestion, improper priority queuing, or other configuration errors in network equipment, this steady stream can become inconsistent with delays between each packet.
How Can I Check My Network's Health?
One of the simplest ways to check the general quality of your internet is to run a ping test. Using a computer's Command Prompt or Terminal, a user can send a basic data packet to another device, website, or server in the form of a “ping”. The recipient device then sends a “ping” back. To show if there is any latency, the time it takes for the sending device to receive a response is measured in milliseconds (ms) and recorded.
Another way to check a network's speed and health is to run a speed test. Speed tests can check for the download and upload speeds of a network and other conditions that may affect the network, like latency, packet loss, and jitter.
✔ You can contact your Internet Service Provider (ISP), Managed Service Provider (MSP), or IT team and request that network diagnostics be performed to verify that the phones will be able to receive a healthy, consistent connection.
It is also recommended to review our Recommended Router Settings and Firewall Rules with your IT Team, Managed Service Provider, or Internet Service Provider to ensure that your network equipment has been configured to allow the phones' traffic.