ICE NAT Traversal Stack

Softil offers a complete ICE NAT traversal solution for developers.

The Softil ICE NAT Traversal Toolkit is a software development tool compliant with the Interactive Connectivity Establishment (ICE) standard developed by the IETF’s MMUSIC working group, comprising the latest NAT-related solutions available for SIP, RTSP, MEGACO/H.248, DIAMETER and others.


Support for Microsoft ICE extensions

Supports all Microsoft-specific firewall and NAT Traversal extensions for STUN, TURN and ICE.

Support for web deployments

Includes support for WebRTC Media, including ICE / DTLS / SRTP / SRTCP single port multiplexing (RFC 5761). For WebRTC applications is used as part of the WebRTC Interconnect Solution.

Support for Trickle ICE

In addition to all standard ICE mechanisms, supports Trickle ICE extensions as per latest IETF Draft draft-ietf-ice-trickle-21 to allow incremental provisioning of ICE candidates.

The toolkit is used to develop:

  • NAT-aware VoIP Clients
  • ICE-ready network elements
  • Terminals
  • Gateways

The NAT Traversal Challenges

With the growing awareness of the advantages of voice and video telephony over the Internet, the need for viable standard-based solutions to traverse NAT are felt by enterprise and home users alike. NAT traversal solutions are necessary to allow transparent communication with anyone, anywhere in the world, while maintaining security and privacy.

The ICE mechanism was developed to solve certain NAT shortcomings. While providing many benefits, NATs can break many existing IP applications, making it difficult to deploy new ones.

Formerly Radvision ICE NAT Traversal ToolKit


The Softil ICE NAT Traversal Toolkit includes the Softil Common Core layer and the Softil STUN NAT Traversal and SDP Toolkits to provide a complete stand-alone solution. It can be used in conjunction with other Softil Stacks, or as a standalone stack. 

The user application itself is built on top of the Signaling Toolkits (one or more), and plugs on top of the ICE NAT Traversal Toolkit.


The ICE NAT Traversal Stack is part of Softil’s SIP Developer Suite, which includes SIP-related toolkits, add-ons, and products that provide all the capabilities a SIP network-element developer needs. The Softil NAT Traversal Toolkit works either in conjunction with other Softil Toolkits or as a standalone implementation.

The ICE NAT Traversal Stack can also be used to solve NAT and Firewall traversal challenges in 3GPP IMS, WebRTC and Internet of Things (IoT) applications.

The ICE NAT Traversal Toolkit comes with

  • Full Source Code Complete source code sample application
  • Full documentation, programmer’s guide and reference guide
  • Porting guide (for unsupported operating systems
  • Training
  • Version upgrades
  • Professional customer support
  • Turnkey solutions (upon request)
  • Porting services (upon request)


ICE NAT Traversal Toolkit Interoperability

All Softil products and solutions take into account interoperability issues between disparate networks, protocols and devices. The ICE NAT Traversal stack has been thoroughly tested for full interoperability.

As a significant contributor in the IETF related working groups (BEHAVE, MMUSIC), Softil contributes and follows closely ICE standardization. This is very important in ensuring interoperability with other ICE implementations and the ability to integrate NAT traversal solutions with different protocols, such as SIP, RTSP, MEGACO and others in different network topologies.

Standards Conformance

  • RFC 5245
  • RFC3489
  • RFC5389
  • RFC 5766
  • MS-ICE2
  • draft-ietf-ice-trickle-21

Common Core

The ICE NAT Traversal Stack is based on Softil’s Common Core, an operating system abstraction layer specifically optimized for communication protocols and embedded platforms. This ensures easy portability of developed products between platforms and operating systems, including those not directly supported by Softil.


Softil ICE-NAT Traversal Toolkit Data Sheet