The Baxter Research Robot's Serial Number is your individual Baxter's unique identifier. It is also the default hostname that can be used to connect to Baxter without previous configuration.
Finding the Serial Number
You can find your Baxter's Serial Number (S/N) on the label on the back of Baxter's waist, near the power button, as shown in the above picture. The serial number, as highlighted in green above, would be '011304P0026'.
Default Robot Hostname
Each Baxter Research Robot comes with the robot computer's hostname set to the serial number of the robot. Baxter can be addressed out of the box using this hostname via Avahi (Link-Local) addressing.
For example, if Baxter's serial number reads 'S/N: 011303P0017', then the hostname will be '011303P0017', and the avahi local hostname will be broadcast as '011303P0017.local'. You can then run commands such as:
$ ping 011303P0017.local
or, resolve the robot's IP address using:
$ avahi-resolve-host-name 011303P0017.local 011303P0017.local 192.168.32.210
Note: Make sure you have the avahi programs installed by running:
$ sudo apt-get install avahi-autoipd avahi-daemon avahi-utils
The default hostname can be changed using the Field Service Menu (FSM).