I am almost too embarrassed to post this...
When I first started out, I went to System Settings - Network and found no way there to do anything like this.
This morning, I discovered there is an application under Sundry called Network Connections. This application makes this process SUPER easy and straight forward.
As a Linux newbie, why that is under "sundry" is beyond me...
Info added Jun 5, 2014:
Unfortunately this does not seem to work. Following this guide, and it's subsequent links, it appears that this will not work until network manager 0.9.9.0 --not yet available for Ubuntu.
I have:
kernel: 3.13.0-27-generic
network manager: 0.9.8.8-0ubuntu7
libnl3: libnl-3-200 v 3.2.21-1
Here is how I have proceeded:
I use dhcp to get my pc's ip address.
sudo gedit /etc/network/interfaces
replace everything with:
#tell network manager to leave eth0 alone
iface eth0 inet manual
# enable loopback interface
#auto lo
#iface lo inet loopback
# start bridge on boot
auto br0
#bridge settings
iface br0 inet dhcp
bridge_ports eth0
bridge_waitport 0 # no delay before a port becomes available
bridge_fd 0 # no forwarding delay
sudo gedit /etc/sysctl.conf
append this:
# Disable netfilter disabled on all bridges
net.bridge.bridge-nf-call-ip6tables = 0
net.bridge.bridge-nf-call-iptables = 0
net.bridge.bridge-nf-call-arptables = 0
WARNING, you will loose your connection at this step:
Run nm-connection and delete all devices there.
Reboot.
nm-applet in system tray says network is not connected, but it is wrong. try accessing a web page.
This is a work in progress...