tommyb52 drop me a line at [email protected]
if you like. I can send you my write up on the Vz IDSL/DDS equipment layout & design.
I designed the 2W DDS IDSL interface during a BA RFP in 1999-2000, and eventually awarded the US Patent that defines the IDSL/DDS, and PG-CAU 15Khz audio loopback operations while I was at Vz.
When a U-BR1TE V or SLC-5 U-BR1TE III is optioned with the D channel OFF, all in-band DDS maintenance loopback messages are translated from the DS0 payload and into the the 16Kb/s ISDL (ISDN DSL) embedded operations channel (eoc) that is part of the 160Kb/s ISDN DSL signal.
With IDSL/DDS you can run all traditional DDS sub-rates, as well as 56/64Kbs. The only kick is that when LiteSpan or any non WeCO/Lucent DLC, is cross-connected to a D4 bank equipped with an Adran U-BR1TE V configured as 1B with the B2 & D channels turned off. ZBS must be turned off on 56K w/SEC CH and with 64Kbs DDS circuits. ZBS function as ZCS (Zero Code Suppression) when the D channel is ON.
In normal ISDN mode when the Adtran U-BR1TE V D channel is ON, the ZBS (Zero Byte Substitution) option when set to ON will allow all zeros' data pattern to pass over AMI coded T1 facilities.
NOTE: With non-WECo/Lucent U-BR1TE's, the IDSL-R must be locally powered.
Only exception to the above is when running any type of IOF channel bank to a WECo/Lucent DLC SLC system (SLC5/96).
The U-BR1TE III at the SLC-5 RT will translate the DDS loopback messages into the IDSL eoc channel. This allows a conventional 4W DDS DS0-DP back to back channel unit design at the CO.