Remote firmware updating on BBBlack

I need help with remote updating the BBBlack based board. I do not want to use SD card. eMMC will be factory programmed with uboot+kernel+file system.Then later on in the field a new image may need to be flashed from

  1. Web thru http
    2)Tftp

Pls let me know if anyone has done this or any pointers how I could do this
Thanks
Anees