Intro

runs on application layer of tcp/ip stack. clear-text protocol also works with browsers or email clients and specific programs.

Do upload/download a file . one ftp connection has 2 channels opened.

1 control channel on tcp port 21 between client and server which returns status codes.

2 data channel via tcp port 20.

active mode - direct . rarely used as client is inside firewall. and server cant reply

passive- common. client initiates data connection to high no. ports instead of server .

TFTP

no auth, on UDP, access based on rw perms of file on server. so works on files that are shared globally and in local / protected networks

commands- connect, get , put , quit, status, verbose. cant list directories

vsftpd

vsFTPd -common in linux

conf file- /etc/vsftpd.conf . users- /etc/ftpusers

anon login

ftp anonymous@ip

hide_ids= yes ls_recurse_enable=YES for rec listing

debug and trace

Download all available files

wget -m --no-passive <ftp://anonymous:[email protected]>