Ethernet boot loader for uploading

Hi, I wonder if someone can provide information regarding the Ethernet flash update program (boot loader and utility) for uploading the image, which reads image back to a remote host from target. I currently used Luminary’s StelleriasWare that provides boot_eth and eflash.exe to download the image to target flash via Ethernet, but it could not read back the image to remote host. If there is other platform has this feature regarding Ethernet upload, please help. Thanks,
Bill