ADTRAN 1200051L6 - Manual (Page 97)

Chapter 10. Troubleshooting
61200051L1-1D ISU 2x64 Dual Port ISDN Service Unit User Manual 83
If the Wrong DTE Port Answers a Call
A common mistake that can easily be made is entering the SPID/
LDN pair swapped between the two DTE ports. For example,
your telephone company has given you two SPID/LDN numbers
as follows:
SPID1 - 201555701111 LDN1 - 5557011
SPID2 - 201555702222 LDN2 - 5557022
If you were to enter the pairs for DTE#1 as SPID1/LDN2 and
SPID2/LDN1, the ISU 2x64 would get confused during incoming
calls because the SPID/LDN pair does not match. Be sure to enter
the SPID/LDN pairs for each DTE# as follows:
Enter SPID dte1 Enter LDN dte1
201555701111 5557011
Enter SPID dte2 Enter LDN dte2
201555702222 5557022
Proper entry of the SPID/LDN pair is crucial to proper operation of the
ISU 2x64.