Softphone
Short answer: A softphone is software that makes and receives phone calls over the internet, usually using SIP, on a computer, tablet or smartphone. It replaces a desk phone with an app: you enter SIP credentials, it registers to the provider, and you can dial and answer calls through a headset or speakers.
Softphones range from free open-source apps to paid business clients. All of them need the same small set of details from your provider.
Definition
The name contrasts software with hardware phones. A softphone implements the SIP user agent, audio codecs and a dial pad in an application.
How it works
- Enter the SIP server, username and password.
- The app registers so incoming calls can find it.
- Outgoing calls are sent as SIP INVITEs; audio is encoded with a shared codec such as G.711.
How it applies to ZuteSIP
Any SIP-compliant softphone works with a ZuteSIP number. Guides on the site cover Zoiper, Linphone, MicroSIP, Bria and Groundwire. ZuteSIP does not publish its own mobile app; if you would rather install nothing, the browser web dialer lets you call from any of your numbers.
Softphone vs web dialer
| Softphone | Web dialer | |
|---|---|---|
| Install | An app such as Zoiper, Linphone, MicroSIP, Bria or Groundwire | Nothing; it runs in the browser |
| Setup | Enter the SIP server, username and password | Sign in to the dashboard |
Related terms
- SIP
- Web dialer
- Codec G.711
- NAT and STUN
Frequently asked questions
Is a softphone free?
Many are, such as Linphone and MicroSIP; others, like Bria, are paid. The number and SIP service are billed separately by your provider.
Do I need a softphone to use ZuteSIP?
No. You can use the browser web dialer, forward calls to any phone, or read SMS in the dashboard.
Why can I call out but not hear audio?
One-way or missing audio is usually a NAT problem. Enabling STUN or switching to TCP or TLS often fixes it.
Can I use the same number in two softphones?
Behaviour with multiple registrations depends on the setup; the SIP troubleshooting guide covers common cases.