My understanding of NFS boot

Following the link http://www.faqs.org/docs/Linux-mini/NFS-Root.html for understanding. Finding out needed things. - Ethernet (10 or 100Mbit) (CONFIG_NET_ETHERNET) is needed - Correct Ethernet driver (assuming that live-CD will have these things by default ) - CONFIG_NFS_FS is needed for NFS support (FUSE will be needed in case of )

• why? Can't I mount root filesystem from NFS otherwise?
• and then what I need to do if I want to mount from HTTP? which option to give in that case?
• http://www.kernel.org/doc/Documentation/filesystems/ramfs-rootfs-initramfs.txt it was great, cleared up many confusions about initRamFS
• http://lxr.linux.no/linux/Documentation/initrd.txt
• Referring http://fxr.watson.org/fxr/source/Documentation/nfsroot.txt?v=linux-2.6 Hoping to get some answers

• It seems CONFIG_ROOT_FS can be entirely ignored
• It is nothing but automatically mounting the NFS filesystem by kernel
• All things done by CONFIG_ROOT_FS can be done from initramfs.

1. Documentation/early-userspace/buffer-format.txt for CPIO format