Learn what Routr is, how this open-source SIP proxy, registrar, and location server from Fonoster works, and how it deploys on Docker and Kubernetes.
Routr is an open-source SIP proxy, registrar, and location server built by Fonoster for teams that need to run their own VoIP or telephony infrastructure. It is designed to be cloud-native, running on Docker and Kubernetes as well as traditional operating systems, and is published as open-source code on GitHub under fonoster/routr.
The project targets telephony carriers, communication service providers, and integrators who want a lightweight, programmable SIP server instead of a heavyweight commercial session border controller or SIP trunking platform.
Routr implements the core SIP server functions of Proxy, Registrar, and Location Service, with configurable routing strategies for intra-domain, domain ingress, domain egress, and peer egress traffic, plus multi-tenant support with domain-level access control lists.
It can be controlled via a command-line interface, a RESTful API, or a web-based GUI, and its modular architecture allows developers to extend behavior with custom Processors and Middleware rather than being confined to built-in functionality.
Routr is free and open source; there is no licensing fee to download, self-host, and modify the software. Costs to an organization are limited to the infrastructure used to run it, such as cloud compute for Docker or Kubernetes deployments.
There is no separate commercial SaaS tier of Routr documented on routr.io; organizations needing managed communications infrastructure would instead look at Fonoster's broader open-source communications platform.
Routr is used to build and operate SIP-based VoIP infrastructure, acting as a proxy, registrar, and location server for telephony carriers, service providers, and integrators.
Yes, Routr is free and open source; there is no license fee for the software itself, only the cost of the infrastructure used to run it.
Routr is developed by Fonoster, a team also known for building an open-source alternative to Twilio's communications APIs.
Yes, Routr is designed to be cloud-native and can be deployed to Kubernetes using Helm, in addition to running on Docker or directly on major operating systems.
Routr is unrelated to networking router hardware; it is software that performs SIP proxy, registrar, and location-server functions for VoIP call routing, not physical network traffic routing.
Yes, Routr exposes a RESTful API for programmatic control in addition to a command-line interface and a web-based GUI.
Routr assumes familiarity with SIP and telephony concepts; it is aimed at engineers and integrators building VoIP infrastructure rather than non-technical users.