Thanks for the note about tftp. I used to use FTP to transfer file from/to my android phone which got me around ~30MB (local transfer), but abandoned it (due to security reasons) for SSH file transfer which only got me ~8MB for local transfer (my phone probably is slow in decrypting). So, I was thinking of keeping SSH file transfer for remote transfer and use tftp (due to its UDP layer) for local transfer. If webdav offered reasonable local transfer speed, I will use it to replace all the above.