If you work with hardware a lot, like upgrading firmware, etc. you'll need a TFTP server for yourself, instead of using internet TFTP server. Why? Because you'll have stable connection and it a must to have stable connection when you upgrading a firmware. Below are steps for building TFTP Server using TFTPD on Ubuntu Server 8.04:

1. installing TFTPD

# sudo apt-get install xinetd tftpd tftp

2. Create /etc/xinetd.d/tftp, then put this:

service tftp
{
protocol        = udp
port            = 69
socket_type     = dgram
wait            = yes
user            = nobody
server          = /usr/sbin/in.tftpd
server_args     = /tftpboot
disable         = no 
}

3. Make /tftpboot

# sudo mkdir /tftpboot
# sudo chmod -R 777 /tftpboot
# sudo chown -R nobody /tftpboot

4. Restart TFTPD

# sudo /etc/init.d/xinetd.restart

Now you can put all the files (e.g. firmware files) in /tftpboot directory. And setup your hardware to point to your machine IP as your TFTP server.