Any know if the DS1 ports on a 15310-CL respond to loopback codes? I am trying to use this in place of installing a bunch of T1 NIU's. Thanks. Natambu Obleton Network Engineer FastTrack Communications nobleton at fasttrackcomm.net <mailto:nobleton at fasttrackcomm.net> (970) 247-3366 office (970) 247-2426 fax