I am assisting the Cisco CCNA semester 3 students with a lab. The students are using the white and green CCNA 3 and 4 Lab Companion Third Edition book. I am on page 171 step B. When I get to the step to configure the router with "encapsulation dot1q 1", I get an invalid command error. The encapsulation option does not even show up in the ? list. Any thoughts? The only thing I can think of is the IOS version. The other 2600's in our lab do the same thing. Please see the attached file for a copy/paste of the commands that were input, including a sh run.