Refer to the exhibit.
Which statement describes DLCI 17?
A.
DLCI 17 describes the ISDN circuit between R2 and R3.
B.
DLCI 17 describes a PVC on R2. It cannot be used on R3 or R1.
C.
DLCI 17 is the Layer 2 address used by R2 to describe a PVC to R3.
D.
DLCI 17 describes the dial-up circuit from R2 and R3 to the service provider.
A DLCI number is a data link connection identifier. Permanent virtual circuits (PVCs) and switched virtual circuits (SVCs) are identified by a DLCI number.
DLCIs have local significance, identify the point between the local router and the Frame Relay switch to which the DLCI is connected.
DLCI is a Frame Relay link-local virtual circuit identifier (to describe) that assign frames to a specific PVC or SVC. DLCI are Layer 2 Addresses that are locally significant.
DLCI does exactly what it says on the tin “data-link connection identifier”. Obviously this is a unique identifier to describe the layer 2 route to another DLCI, hence a route between routers.
DLCIs are locally significant, meaning between the frame switch and the customer router only. In labs we will typically see the PVC from, for example, R1 to R2
Layer 2
L23