Zhone Technologies Network Device manual Toward WAN Voice Single Data Super-rate Without

Zhone Technologies, Inc.			IMACS Product Book, Version 4
Toward WAN 2
	Voice	Voice	Single Data	Super-rate
	Without	With	DS0	Data
	Singaling	Singaling	(64Kbps)	(Nx64Kbp
				s)
Set Transmit ABCD Signaling Bits	N/A	Yes	N/A	N/A
Monitor Status of Transmit ABCD	N/A	Yes	N/A	N/A
Signaling Bits
Monitor Status of Receive ABCD	N/A	Yes	N/A	N/A
Signaling Bits

Benefits of Built-In Diagnostics

The real power of the integral diagnostics of the IMACS can be fully appreciated when the individual diagnostic tools are applied to everyday troubleshooting such as the one illustrated in the following example.

The environment shown in Figure 44 consists of two IMACS’ connected by a T1 line. These are referred to as the Local IMACS and the Remote IMACS respectively. At the local IMACS, the DTE equipment is a co-located device providing a 56 Kbps V.35 interface that is connected to a V.35 HSU port. At the Remote IMACS, an OCU- DP card that interfaces to the 4-wire DDS tail-circuit extends the 56 Kbps to a third location. Consequently, the Remote IMACS is equipped with an OCU-DP card that interfaces to the 4-wire DDS tail-circuit. At the third location, the DDS circuit terminates in a generic, third party DSU/CSU that in turn provides a 56 Kbps V.35 interface to the remote DTE device.

The system operator can use the diagnostic tool kit to systematically troubleshoot the problem on an end-to-end basis and to identify the faulty sub-system, even if it is external to the IMACS. One way to systematically troubleshoot the problem is illustrated in Figure 44. While there are many other approaches, in general, the procedure to follow is to combine loop backs that are generated either through software commands or via industry- standard loop-up codes with Bit Error Rate Tests (BERTs) for data circuits, or test tones for voice circuits. In the IMACS, all of those tools are available as integral features of the system and of the various cards. Each test determines if a specific sub-system is operating properly. In our example, after each test, the sub-systems that are shown to be functioning properly are shaded in gray.

In Figure 44, the local HSU card is put in Local loop back and a BERT test is run from the DTE. If successful, in Figure 44, diagnostics-figure 3, the loop back sequence is advanced by putting the T1 link of the Local IMACS in Local loop back and running BERT test again. This also tests the cross-connect element of the local IMACS if there is one present. In Figure 44XX, diagnostics-figure 4, the T1 link of the remote IMACS is configured in Line Loop back. Alternatively, a loop up code can be sent from the local IMACS to put the T1 link of the remote IMACS in Line loop back. This process is repeated until the remote DTE is put in network loop back and tested as shown Figure 44, diagnostics-figure 8.

March 2001 Page 107