As an intelligent network emulator, Maxwell can perform impairments on both packets and on protocols, and it does so intelligently. In addition, the user may create custom impairments for specific applications.

The Maxwell Intelligent Network Emulator can accept a user-written plugin. You can use a plugin to create various impairment scenarios (including packet modification).

That plugin gets the benefit of the already existing flow classification system. That plugin can itself apply even more detailed selection criteria, including protocol state tracking, and it can do pretty much anything to a packet that it would like to do - copying it, rewriting it, sending it back to the sender, etc, etc.

Without a plugin, Maxwell will classify incoming packets into flows and then apply a set of standard impairments (drop, duplication, delay, jitter, and reordering) to the packets in each flow. Both the flow definitions and the specific impairments may be enabled, disabled, and configured under user control.

With a plugin, Maxwell will invoke the plugin to process each packet after that packet has been subjected to the standard impairments, if any, for each defined flow. In this stage, users can write plugins to perform real-time packet modification as well as other user defined impairments. For example, you can zero IP/TCP/UDP Checksum, zero source or destination IP address, swap bytes in IP header or in IP data, reorder packets according to some patterns, force fragmentation, or modify payload etc.

If you have a specific idea for a plugin that would be useful for your work or application, but need some guidance on how to implement it, or you wish InterWorking Labs to create it for you, please contact maxwell-support.

For more information on creating your own plugin, please see the Maxwell Plugin Programmer's Guide.