A firmware image file that is typically used in embedded systems such as routers. A TRX file includes a header with the following information: file checksum--used to ensure that the file has not been modified which helps to assure that malicious code has not been inserted which could compromise the device or the security of the device--, a file length, and the node offsets within the file. The file can be used for the update or recovery of the firmware that is stored in ROM on the device.