Chapter 5.Testing24 ISU 2x64 Dual Port ISDN Service Unit User Manual 61200051L1-1DFigure 5-2Test Menu TreeLoopback DTEThis test causes the DTE port to loop back toward user equip-ment. This allows a bit error rate test (BERT) to be performedfrom the local end-user equipment to the ISU 2x64 to verifyproper cable connection, etc. Either a BERT tester or DTE datapacket test must be used for this test.Loopback NetworkThis test forces the ISU 2x64 to loop back both the B1 and B2channels toward the network. This can be used to allow a far-enduser to perform a BERT all the way through the network.Loopback ProtocolThis test causes data to be looped back toward the network afterpassing through a selected protocol such as T-Link or BONDING.See Figure 5-3 for loopback points.Figure 5-3Loopback Points1=STATUS2=TEST3=CONFIG4=DIAL1=Loopback DTE2=Loopback Netw.3=Loopback Proto4=Loopback Remot5=Test Remote6=Lpbk Disable7=NEBE/FEBE8=Software Ver9=Lpbk Both DTEs10=Test 2047 Both1=No Rem Lpbks2=DDS Accepted3=V.54 Accepted4=DDS+V54 AcceptNETIFCERATEADAPTION DTEIFCENETWORK Network ProtocolDTEDTE
