Review Questions

Answers to the review questions can be found in Appendix A, "Answers to Review Questions."

1:	What is the scope of the I.431 and I.432 standards?
2:	Where does the name D channel come from? What are the operational speeds of the D channel for BRI and PRI?
3:	What is a V-reference point in ISDN?
4:	What are the important pins in a S/T interface?
5:	What is the modulation of the ISDN U-interface?
6:	What is the bit rate of the S/T interface and U-interface?
7:	How many INFO messages participate in the BRI's Layer 1 initialization? What does INFO0 mean?
8:	Which bit in the ISDN frame indicates line activation?
9:	What makes up DLCI in ISDN? What is the length of DLCI, TE, and SAPI?
10:	What are the two indicators that Layer 2 is active?
11:	What does TE = 127 mean?
12:	What is the dynamic range of TEI?
13:	What does SAPI = 0 indicate ?
14:	How do you distinguish an incoming from an outgoing call?
15:	Which ISDN protocol provides information about Bearer capability. Name three basic types of Bearer capabilities.