SIP Trunking

Enable IP-based communication by connecting phone system directly to the internet.

What is SIP trunking?

SIP trunking is the virtual version of an analog phone line. Unlike the PSTN, ISDN BRI, or T1 lines that rely on physical wiring, it converts voice signals into digital packets, which are then transmitted over the Internet Protocol (VoIP) technology.

By using Session Initiation Protocol (SIP), companies can consolidate their voice and data networks, resulting in cost savings and streamlined operations. The service is usually provided by an Internet Telephony Service provider (ITSP) and often works with SIP-based business phone system (PBX) to enable daily functions of audio & video calls.

Why SIP trunking over the legacy phone lines?

SIP trunking offers numerous advantages over legacy phone lines, making it an attractive option for businesses.

Leverage a modern phone system: Directly connect Yeastar phone system to the SIP Trunk and embrace easy-first unified communications with a suite of advanced features. You can go on-premise or cloud-based, the choice is yours.

Cost savings: Eliminate physical phone lines and related hardware costs, resulting in lower monthly expenses for line rental and DID.

Easy scalability: Add or remove SIP trunks as your communication needs change, ensuring flexibility and cost-efficiency.

Uninterrupted connectivity: Continuous communication is assured with the internet connection, providing a reliable backup solution in case of traditional landline failures.

Expanded geographic reach: No location constraints. Easy to move office locations with original numbers.

Enhanced customer experience: Add regional and international numbers to your sip relay for more choices at a lower cost, improving convenience for customers.

How does SIP trunking works?

sip trunk topology diagram

SIP trunking establishes a connection between your business phone system and the Internet Telephony Service Provider (ITSP) through the Internet. Voice and data traffic are transmitted over this connection, allowing for voice, video, messaging, and more communication features.
There are two options for implementation:

Option 1: Using a Gateway

If you are using an analog phone system that doesn’t support the SIP trunk, you will need a VoIP gateway that acts as a bridge between the existing PBX system and the SIP trunk. The gateway translates the voice signals from the PBX into digital packets compatible with IP networks, allowing communication with SIP-based service providers.

Option 2: Adopting a Modern PBX System

Alternatively, you have the option to directly purchase a modern phone system with native SIP support, eliminating the need for additional gateways. Once connected, SIP trunking enables efficient and cost-effective communication, allowing businesses to make and receive calls over the Internet using VoIP technology.
Learn more about the Yeastar modern phone system. →

Selecting the Right ITSP

If you are ready to transition from traditional phone lines to SIP trunking, it is crucial to carefully select an Internet Telephony Service Provider (ITSP). Consider the following important factors:

Security & compliance

Competitive pricing

Technical support

Network Control

Extensive network coverage

Ability to port all phone numbers

Compatibility with existing phone system

Yeastar understands these factors and is committed to ensuring interoperability with global ITSP partners through in-depth testing. Until now, Yeastar has 120+ ITSP partners worldwide. These SIP trunking providers have been tested for compatibility with all series of Yeastar phone systems. Also, Pre-configured templates are included in the PBX management portal to make configuration easy and quick for you.

Check the full list of Yeastar certified SIP trunk providers.

Common FAQs

How to set up a SIP trunk in Yeastar phone system?


For P-Series Phone System: Appliance Edition | Software Edition | Cloud Edition

For S-Series VoIP PBX: Configuration Guide

For P-Series Phone System: Appliance Edition | Software Edition | Cloud Edition

For S-Series VoIP PBX: Configuration Guide


What is the difference between SIP and VoIP?


Related Features

Yeastar P-Series Phone System

The complete communications solution

Available both in the cloud and on-premises, Yeastar P-Series Phone System unites calls, video, omnichannel messaging, integrations and more in one simple system for your seamless communications anywhere.

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