As part of a broader organisational restructure, data networking research at Swinburne University of Technology has moved from the Centre for Advanced Internet Architecture (CAIA) to the Internet For Things (I4T) Research Lab.

Although CAIA no longer exists, this website reflects CAIA's activities and outputs between March 2002 and February 2017, and is being maintained as a service to the broader data networking research community.

MAPPING -- Measuring And Practically Predicting INternet Growth

Measuring and predicting growth in Internet addressing, routing complexity and energy usage

NAT Test

This test allows you to find out whether you are behind a Network Address Translator (NAT). On the results page you will see your external/public and internal/private IPv4 addresses. The NAT test only works if your browser can execute Java applets. If you do not have Java installed, click on the test button below and follow the instructions of your browser to install Java or alternatively visit the Java Download page.

Click the button below to start the test. Note that after you have clicked the button your browser may ask you for permission to excute the Java applet. Please click on either the Always run on this site or Run this time button. If a popup window appears after that, please click on the Run or OK button. Warning: sometimes Java may be installed but is not working; in this case please consult the Java Help Center.

Note that all test results are logged for research purposes, but we will keep all observed IP addresses confidental.

This project has been made possible in part by grants from APNIC for a project titled "Exploring the Utilisation of IPv4 Address Space and Size of the NATed IPv4 Internet" and an ARC linkage grant with APNIC as partner organisation for a project titled "Tools and models for measuring and predicting growth in internet addressing and routing complexity" (project LP110100240). The research has also been supported by Australian Research Council grant FT0991594.

Last Updated: Monday 30-Mar-2015 17:57:33 AEDT | Maintained by: Sebastian Zander ( | Authorised by: Grenville Armitage (