Bootloader or flashloader??

Hello,

I spent a couple of hour without understanding Bootloader / flashloader.

 

I have to made something for updating the firmware ... but i don't know what is the right way to do it.

The hardware :

    - i have an sdcard with fileX for storing the image file to be updated.

    - I have an ethernet with ftp services to push the image.

    - Maybe an 32mbytes SDRAM

So my wishes is to put the image on the sdcard with ftp, to make an firmware update witout using the SDRAM.

If this is to complicate, my wishes is to use the SDRAM :

  - sd card for storing the image

 - ethernet with ftp to push the image into sdcard

 - sdram for storing the image from sdcard, and relocating the flashloader in sdram for flashing

 

if someone can help me with example.

 

thanks a lot