What’s New in Kamailio v6.0.0? Modules, Improvements, and Kamailio Upgrade Guide

If you’re building real-time VoIP systems and if Kamailio is an essential part of your stack, you must’ve heard about the release of the new version: Kamailio 6.0.0. And well, it is something to be excited about. The Kamailio 6.0.0 stable release marks a significant evolution in the SIP server’s capabilities, not just in terms of performance, but also in how developers interact with modules, configure behavior, and deploy Kamailio in scalable environments.

If you’re still working with Kamailio 5 modules or looking to install Kamailio 6.0.0 for a fresh deployment, here’s your essential breakdown of the release.

Core Highlights of Kamailio v6.0.0

This release makes Kamailio more flexible and production-ready.

• Multi-threaded UDP support: You can now receive SIP traffic on UDP sockets using multiple threads for better concurrency.
• Listen on a range of ports: A single socket definition can now specify a range of ports; useful for containerized environments and NAT scenarios.
• Dynamic function parameters: Most module functions now accept variables as parameters, enabling smarter, template-driven config logic.
• CMake support: Developers can now build Kamailio using CMake as an alternative to make, offering improved flexibility in custom builds.
• Linked internal libraries: Internal libraries now link directly to the core, improving performance and binary packaging.

Kamailio New Modules in v6.0.0

Kamailio v6.0.0 introduces five main new modules, each focused on improving SIP routing, presence, and extensibility.

1. ims_qos_npn
Adds an enhanced version of the IMS QoS implementation, focused on network performance enforcement in IMS setups.

2. nghttp2
Enables Kamailio to act as an HTTP/2 server using the nghttp2 library, allowing integration with HTTP/2-based service flows.

3. presence_dfks
Adds support for Device FeatureKey Synchronization (DFKS) in presence systems, useful for real-time device status tracking.

4. pvtpl
Allows evaluation of template files that include Kamailio config variables. This is ideal for templated routing logic and flexible configs.

5. topos_htable
Provides hash table storage for the topos module, improving performance in topology hiding and SIP header processing.

Also read: Why Should You Use Kamailio in Your VoIP Infrastructure?

New Capabilities in Existing Kamailio Modules

Kamailio 6.0.0 also strengthens key modules and SIP processing logic. 

• HTTP/2 Enhancements: Kamailio can now read HTTP response headers in the client module and serve HTTP/2 via nghttp2.
• Async event handling: A new event route enables asynchronous processing of key-value pairs. For example, in logging pipelines.
• Per-request authentication algorithm: Kamailio can now set the hashing algorithm (e.g., MD5, SHA-256) on a per-request basis.
• Improved STIR/SHAKEN: The Secsipid module includes expanded identity verification options.
• Stateless forwarding updates: New functions let you forward SIP requests in stateless mode using a single Via header.
• SCA flexibility: More control over setting the From/To URIs for Shared Call Appearance scenarios.

Install Kamailio 6.0.0 with Updated Tools

You can install Kamailio 6.0.0 by compiling from source or using binary packages.

To build from source:

1. Clone the 6.0 branch from GitHub.
2. Run make cfg or cmake to generate build files.
3. Use make all && make install, or the CMake equivalent.
4. Include modules like db_mysql, tls, etc., using the include_modules variable.
5. Start Kamailio using either systemd or init.d scripts provided in the build.
   

Binary packages for Debian, Ubuntu, CentOS, Fedora, and OpenSUSE are available as soon as they are built or submitted.

For step-by-step instructions, refer to the Kamailio 6.0 Install Guide.

Performance, SIP Processing & Observability Upgrades

Several runtime and operational features were added to help with observability, config control, and modern SIP routing:

• DNS cache from file
  Kamailio can now load DNS cache entries from a local file, letting it run without relying on a live DNS server.
  
• Prometheus support
  Metrics like uptime and private memory usage are now exported. You can also tag the metrics to organize monitoring dashboards.
  
• Enhanced TCP attributes
  New variables in the tcpops module expose active TCP connection details. This is useful for diagnostics and connection handling.
  
• RabbitMQ lazy start
  RabbitMQ can now be initialized without requiring an immediate connection, ideal for staged or delayed service startup.
  
• Kafka enhancements
  Additional configuration parameters give you more control over Kafka behavior in message-driven environments.
  
• Kamcli improvements
  The modern CLI tool now supports more commands, interactive suggestions, syntax highlighting, and output formatting.
  

These updates help simplify scaling, monitoring, and deploying Kamailio across modern infrastructure stacks.

When Should You Upgrade?

You should upgrade to Kamailio v6.0.0 if:

• You’re starting a new VoIP or IMS deployment.
• You need HTTP/2 integration or presence features like DFKS.
• You’re building flexible, templated routing logic.
• You need better metrics and diagnostics for observability.
• You’re running on containers or orchestrated systems and want a cleaner startup and control.

If you’re still on Kamailio 5.x, the improvements in SIP handling and modular control make this upgrade definitely worthwhile.

Kamailio v6.0.0 is more than a version bump. It aligns the SIP server with modern infrastructure demands like better config logic, cleaner runtime control, HTTP/2 support, and smarter integrations. If you’re serious about scalable Kamailio solution development, this release lays the right foundation.

Whether you’re modernizing an old Kamailio deployment or building a new one from scratch, we can help architect, deploy, and scale your SIP infrastructure flawlessly. Talk to our Kamailio experts today!

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