Debug output varies depending on the type of information that arrives, and there are many different types of messages with different options. For more information regarding output for the debug commands, go to http://www.cisco.com/en/US/products/sw/iosswrel/ps1831/products_command_reference_chapter09186a00800eea80.html#1017611.
A educational overview of the history and workings of T1s appears at http://www.techfest.com/networking/wan/t1.htm.
Debug output varies depending on the type of information that arrives, and there are many different types of messages with different options. For more information regarding output for the debug commands, go to http://www.cisco.com/en/US/products/sw/iosswrel/ps1831/products_command_reference_chapter09186a00800eea80.html#1017611.