Toning/Tracing - Do you have network cables that you do not know what they are for, or where they connect? I can tone and trace those cables from either end.
Testing - For the most part, network connections should be terminated using the T-568B standard. If you have network connections that do not work, it's possible the termination is incorrect and the only way to find out is to test the cable for proper termination.
Labeling - Once a cable is tone/traced, it's a great idea to label those connections on both ends so future connectivity or troubleshooting will be more straight-forward.
Cable Certification - Cable Certifying services are available. Call for more details.