Integrated Services Digital Network (ISDN) - Narrowband Multi-service Delivery System (NMDS) - Part 4: Test Suite Structure and Test Purposes (TSS&TP) specification for the network layer (NTN side)
V interfaces at the digital Local Exchange (LE) - V5.1 interface for the support of Access Network (AN) - Part 1: V5.1 interface specification (incl. Diskette!!!)
Integrated Services Digital Network (ISDN) - Narrowband Multi-service Delivery System (NMDS) - Part 7: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) specification for the PSTN NMDS interface Layer 3 (NTN side) (incl. Diskette!!!)